Synthesis and chemistry of bis(triisopropylphosphine) nickel(i) and nickel(0) precursors

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Synthesis and chemistry of bis(triisopropylphosphine)

nickel(^I) and nickel(0) precursors†

Cite this: Dalton Trans., 2013, 42, 1461

Robert Beck, Manar Shoshani, Jonathan Krasinkiewicz, Jillian A. Hatnean and

Samuel A. Johnson*

High yield syntheses of (ⁱPr₃P)₂NiX (3a–c), (where X = Cl, Br, I) were established by comproportionation of

(ⁱPr₃P)₂NiX₂(1a–c) with (ⁱPr₃P)₂Ni(η²-C₂H₄) (2). Reaction of 1a with either NaH or LiHBEt₃provided

(ⁱPr₃P)₂NiHCl (4), along with 3a as a side-product. Reduction of (ⁱPr₃P)₂NiCl (3a–c) with Mg in presence of

nitrogen saturated THF solutions provided the dinitrogen complex [(ⁱPr₃P)₂Ni]₂(μ-η¹:η¹-N₂) (5). In aromatic

solvents such as benzene and toluene a thermal equilibrium exists between 5 and the previously

reported monophosphine solvent adducts (ⁱPr₃P)Ni(η⁶-arene) (6a,b). Reaction of 5 with carbon dioxide

provided (ⁱPr₃P)₂Ni(η²-CO₂) (7). Thermolysis of 9 at 60 °C provided a mixture of products that included

the reduction product (ⁱPr₃P)₂Ni(CO)₂(8) along with ⁱPr₃PvO, as identiﬁed by NMR spectroscopy.

Complex 8 was also prepared in high yield from the reaction of 5 with CO. Reaction of 5 with CS₂gave

the dimeric carbon disulﬁde complex [(ⁱPr₃P)Ni(μ-η¹:η²-CS₂)]₂(9). Diphenylphosphine reacts with 5 to

form the dinuclear Ni(^I) complex [(ⁱPr₃P)Ni(μ₂-PPh₂)]₂(10). Complex 5 reacts with PhSH to form (ⁱPr₃P)₂Ni-

(SPh)(H) (11), which slowly loses H₂and ⁱPr₃P to form the dimeric Ni(I) complex [(ⁱPr₃P)Ni(μ₂-SPh)]₂(12) at

room temperature. Complex 12 was also accessed by salt metathesis from the reaction of (ⁱPr₃P)₂NiCl (3a)

with PhSLi, which demonstrates the utility of 3a as a Ni(^I) precursor. With the exception of 6a,b, all com-

pounds were structurally characterized by single-crystal X-ray crystallography.

Received 31st August 2012,

Accepted 27th October 2012

DOI: 10.1039/c2dt32008h

www.rsc.org/dalton

i

bulky phosphine donor Pr₃P have been reported; for example,

Introduction

a search of the CSD⁷for the (ⁱPr₃P)₂Ni fragment provided 6

Over the past decade increased eﬀorts have been made to entries, 4 of which we have published in the last 2 years. We

expand the utility of Ni in catalysis, driven by its greater avail- have found that bulky Ni(0) precursors can change the course

ability and lower cost compared precious metal catalysts. Com- of reactivity, and that the chemistry of the ⁱPr₃P ligand is often

plexes of Ni are capable of a variety of cross-coupling significantly diﬀerent from that of slightly less bulky phos-

reactions,¹as well as the activation of traditionally inert C–H, phines such as Et₃P,^6band allows the isolation of unexpected

C–F, and C–O bonds.²These inert bond activation reactions reaction intermediates.⁸Reactions of (ⁱPr₃P)₂Ni(0) precursors

i

include catalytic transformations^2asuch as the unprecedented also appear prone to loss of Pr₃P and the formation of com-

stannylation of C–H bonds,³coupling reactions with C–F plexes containing either the (ⁱPr₃P)Ni(0) or (ⁱPr₃P)Ni(I)

bonds,^2a,4and C–O bond hydrogenation and coupling reac- moiety.^6eUnlike the coordination chemistry of nickel centers

tions.^2b,e,f,5Phosphine supported complexes of low-valent in the 0 and +2 and oxidation state, the chemistry of Ni(^I) com-

nickel complexes play a role as catalysts or intermediates in plexes is less well developed. Mononuclear complexes of the

many of these reactions.

type (Ph₃P)₂NiX⁹and related systems with tri-alkyl, aryl or bis-

Our research has probed the use of phosphine supported chelating-phosphines have been described¹⁰as reactive inter-

Ni(0) synthons, such as the anthracene complex (ⁱPr₃P)₂Ni(η²- mediates of redox reactions via EPR-spectroscopy or

C₁₄H₁₀), in the isolation of Ni(0) intermediates in reactions electrochemically.¹¹Despite the synthetic potential of such

that include C–H, C–F and C–C bond activation.^2a,3,6Surpris- precursors, high-yield synthetic routes to (R₃P)₂NiX species,

i

ingly few fully-characterized complexes of the readily available where R is a large electron-donating substituent such as Pr,

are not well-known.

Herein, we report the high yield syntheses of the Ni(^I) pre-

Department of Chemistry and Biochemistry, University of Windsor, Sunset Avenue

cursors (R₃P)₂NiX (X = Cl, Br, I) and the Ni(0) precursor

401, Windsor, ON N9B 3P4, Canada. E-mail: sjohnson@uwindsor.ca;

[(ⁱPr₃P)₂Ni]₂(μ-N₂) (5), along with some reactions showing their

Fax: (+1) 519-973-7098

synthetic utility in the preparation of Ni(0), Ni(^I) and Ni(II)

complexes.

†CCDC 896745–896759. For crystallographic data in CIF or other electronic

format see DOI: 10.1039/c2dt32008h

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Preparation and characterization of (ⁱPr₃P)₂NiX₂(X = Cl, Br, I)

(1a–c)

Heterogeneous mixtures of powdered, anhydrous NiX₂(X = Cl,

Br, I) react within a period of 3 d in toluene in the presence of

two equivalents ⁱPr₃P to provide (ⁱPr₃P)₂NiX₂(1a–c) as analytically

pure dark red rhombic crystals in almost quantitative yields

(94–97%). Complexes 1a–c are far less soluble in toluene (2 g per

150 mL), when compared to the triethylphosphine congeners

(PEt₃)₂NiX₂. Syntheses of complexes 1a and 1b have been

reported previously;¹²however, the reported syntheses in EtOH

provided lower yields.^12bFull characterization is lacking in the

1

literature even for the previously reported compounds. The H

and ¹³C{1H} NMR spectra of 1a–c are nearly identical. The co-

i

1

ordinated Pr₃P ligands in 1a–c show two sets of H resonances

with a doublet for the methyl substituents at δ ∼ 1.2 and a septet

at δ ∼ 2.2 for the C–H group of Pr₃P ligand. The ¹³C{¹H} NMR

i

spectra feature a singlet at δ 20.2 and a broad singlet at δ 23.1.

Complexes 1a–c do not have an observable ³¹P{¹H} NMR signal

at room temperature, consistent with the failure to observe coup-

ling to ³¹P in both the ¹H and ¹³C{¹H} NMR spectra. This

suggests rapid relaxation of the ³¹P nuclear spin by a contact

mechanism from a thermally accessible electronic triplet spin

state. Under some conditions ³¹P{¹H} NMR spectra of solutions

of 1a–c provide singlets, with chemical shifts (1a, δ 21.0; 1b, δ

i

22.0; 1c, δ 24) that are suggestive of dissociation of free Pr₃P

(δ 20.5). Dilute samples of 1b and 1c dissolve with a green color,

also suggestive of complicated solution behavior. Eﬀorts to

prepare (ⁱPr₃P)₂NiF₂from NiF₂using similar reaction conditions

failed, despite precedent for closely related reactions.¹³

Scheme 1 Syntheses of Ni(I) reagents 3a–c from 1a–c and 2 and ORTEPs of

their solid-state structures with 30% probability ellipsoids.

The molecular structures of 1a–c were characterized by single-

crystal X-ray diﬀraction techniques, and for 1a and 1b feature the

expected square planar coordination geometries. A lower-quality

disordered room-temperature structure of 1b has been obtained

previously.¹⁴The iodo derivative 1c has a slight distortion away

from square planar towards tetrahedral, as shown in Scheme 1.

The distortion is presumably due to the steric requirements of

the bulky ⁱPr₃P and iodo ligands. The bond angles I(1)–Ni(1)–I(2)

and P(2)–Ni(1)–P(1) deviate from linearity by 26° and 17°,

respectively. A summary of bond lengths is provided in Table 1.

It has been previously shown that (ⁱPr₃P)₂Ni(η²-C₂H₄) (2)

can be prepared in moderate yield from the reaction of Ni

Complex 2 is very soluble in n-pentane and concentrated

solutions at –34 °C aﬀorded single crystals suitable for X-ray

crystallography. The structure is typical for Ni(0) bis(phos-

phine) adducts. The C(1)–C(2) bond length of 1.386(3) Å for

the π-coordinated ethylene is slightly elongated when com-

pared to free ethylene (1.340 Å)¹⁶and closely related with the

structural parameters of the related literature complexes

(dtbpe)Ni(η²-C₂H₄)¹⁷[dtbpe = 1,2-bis-(di-tert-butyl-phosphino)-

ethane] and (PPh₃)₂Ni(η²-C₂H₄).¹⁸

Preparation and characterization of (ⁱPr₃P)₂NiX (X = Cl, Br, I)

(3a–c)

i

(C₂H₄)₃with Pr₃P.¹⁵A more convenient synthesis is the reac-

tion of 1a–c with magnesium in the presence of ethylene, as

shown in eqn (1). The reaction aﬀorded yellow crystals of the

16e⁻complex 2 in 83% yield.

Solutions of (ⁱPr₃P)₂NiX₂(1a–c) with

a slight excess of

(ⁱPr₃P)₂Ni(η²-C₂H₄) (2) in n-pentane undergo comproportiona-

tion to aﬀord (ⁱPr₃P)₂NiX (3 h for 3a, 30 min for 3b, 5 min 3c),

as shown in Scheme 1. A similar approach was reported for

PPh₃supported Ni complexes.¹⁹The progress of the reaction

can be visually monitored by the slow dissolution of the spar-

ingly soluble (ⁱPr₃P)₂NiX₂(1a–c) in n-pentane. Complexes 3a–c

were easily isolated by removal of the volatiles under vacuum

and washing the residue with ice cold n-pentane to remove the

slight excess of 2.

The eﬀective magnetic moments (μ_eﬀ) of 3a–c were deter-

mined using Evans method to be in the range of 2.05–2.19 μ_B,

which is in agreement for other d⁹nickel complexes with one

ð1Þ

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Table 1 Selected bond lengths [Å] and angles [°] of basic mono- and di-halogeno bisphosphine nickel complexes 1a–c and 3a–c

1a

1b

1c

3a

3b

3c

4

Ni–X [Å]

Ni–P [Å]

2.193(2)

2.2572(11)

2.3195(5)

2.2898(10)

2.5102(7)

2.3098(13)

2.2896(12)

2.1761(7)

2.2215(5)

2.3033(7)

2.2230(7)

2.4810(7)

2.2336(10)

2.2402(10)

2.2062(7)

2.1845(7)

2.1858(7)

P–Ni–P [°]

X–Ni–X [°]

P–Ni–X [°]

180.0

89.55(6)

180.0

90.63(3)

163.71(5)

154.24(3)

92.18(4) 92.29(4)

119.44(2)

—

120.282(12)

120.18(3)

—

119.911(17)

126.05(4)

—

119.02(3) 114.93(3)

163.10(2)

178.8(12)

98.21(3) 98.64(3)

1

unpaired electron.^10b,20The H NMR spectra of paramagnetic

3a–c, show broad paramagnetically shifted resonances for the

i

methyl groups of the Pr₃P moieties in the range of δ 3.1–3.3,

and the methine C–H at δ 50–60. Although the EPR spectra

and reactivity of complexes 3a and 3b have been previously

reported,²¹high-yield syntheses and complete characteri-

zations have not.

Complexes 3a–c are stable in the solid state for months at

−34 °C without any signs of decomposition. Solutions of 3a–c

in aromatic solvents such as toluene and benzene start to

decompose within a period of 24 h by disproportionation,

which yields (ⁱPr₃P)₂NiX₂(1a–c) and a nickel mirror, but

n-pentane solutions of 3a–c are significantly more stable.

Single crystals of 3a–c suitable for structural analysis were

obtained by cooling concentrated n-pentane solutions to

−34 °C. Depictions of the solid-state molecular structures are

shown in Scheme 1, and X-ray crystallographic bond lengths

and angles are provided in Table 1.

ð2Þ

The solid-state structure of 4 has not been reported, and we

were interested in how the structural parameters of 3a might

diﬀer from 4, to ensure that these species could be easily dis-

tinguished by crystallography. A comparison of the bond

lengths and angles of 1a–c, 3a–c and 4, are given in Table 1.

The presence of a hydride ligand in 4 is obvious from the P(1)–

Ni(1)–P(2) angle of 163.10(2)°, which is smaller than the 180°

angle in 1a and larger than the 119.44(2) angle in 3a. The

phosphine donors in 4 are bent away from the larger chloro-

ligand. The electron density associated with the hydride ligand

was located in diﬀerence Fourier map and lies with a Ni(1)–

H(1) distance of 1.25(3) Å, though this short distances must be

considered suspect in the absence of neutron diﬀraction data,

particularly when compared with typical literature terminal

Ni–H distances.^7,23a–c,e

Complexes 3a–c feature trigonal planar geometries around

the nickel atom, with sums of X–Ni–P and P–Ni–P angles that

are within 1° of 360°. The Ni–X and Ni–P bonds are all shorter

in 3a–c than in the related Ni(^II) complexes 1a–c, which may be

attributable to decreased steric bulk about the three-coordi-

nate vs. four-coordinate metal centres, rather than reflective

of the relative sizes of Ni(^I) versus Ni(II). A striking structural

feature is the similar P–Ni–P angles in the chloro and

bromo derivative 3a–b of 119.44(2)° and 120.18(3)°, but the sig-

nificantly larger P–Ni–P angle of 126.05(4)° in the iodo deriva-

tive. This complex also features dissimilar P–Ni–I bond

angles of 119.02(3) and 114.93(3)°. A slight rotation of one of

Synthesis and characterization of dinuclear dinitrogen

complex (5)

The reduction of (ⁱPr₃P)₂NiCl (3a) with an excess of mag-

nesium in THF aﬀorded the red complex [(ⁱPr₃P)₂Ni]₂(μ-N₂) (5)

in 78–85% yield, as shown in eqn (3). Dinitrogen complex 5 is

extremely soluble in n-pentane, and after extensive drying

under vacuum left a dark red waxy solid. Both the ³¹P{¹H} and

¹³C{¹H} NMR spectra of THF solutions of (ⁱPr₃P)₂NiCl (3a)

under the reducing conditions used to prepare 5 provided no

evidence for Ni(0) complexes with more than two ⁱPr₃P

i

the Pr₃P moieties in 3c may occur to accommodate the larger

iodo ligand, and this may account for the increase in P–Ni–P

angle.

Structural characterization of (ⁱPr₃P)₂NiHCl (4)

Attempts to generate 3a directly from 1a using alternate redu- ligands, examples of which are known for the smaller phos-

cing agents failed to provide improved yields compared to the phine ligands such as PEt₃.²⁴This might be expected, given

i

reaction of 1a with 2. For example, the reaction of 1a with a the large 160° Tolman cone angle for Pr₃P,²⁵which should

slight excess of sodium hydride or LiHBEt₃in THF provided a prevent the formation of complexes such as (ⁱPr₃P)₃Ni, though

mixture of the known^12b,22complex trans-(ⁱPr₃P)₂NiClH (4) the complex (Cy₃P)₃Ni has been reported and used in syn-

with 3a as a significant byproduct. Complex 4 was readily iso- thesis²⁶despite the similar phosphine cone angle of Cy₃P. Full

lated by removal of solvent under vacuum, extraction with cold structural characterization of (Cy₃P)₃Ni has not been reported.

n-pentane, removal of the less soluble alkali metal chlorides Solid 5 can be handled at 20 °C for weeks without significant

and the Ni(^I) byproduct (3a) by filtration, and crystallization at decomposition, but gradually decomposes in polar organic sol-

−34 °C.

vents such as THF. The ³¹P{¹H} NMR signal of 5 was observed

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at δ 43.7. Dinitrogen incorporation is confirmed by the broad

The core of the molecular structure of 5 has approximate D₂

singlet at δ −71.2, in the ¹⁵N{¹H} NMR spectrum of ¹⁵N₂symmetry, approaching an approximate D_2d, or allene-like

labeled 5, which is only modestly shifted relative to the chemi- structure. The plane containing the atoms Ni(1), P(1) and P(2)

cal shift of free N₂. Due to the symmetry of complex 5, no are almost perpendicular to the second plane consisting of

absorption band was observed in the IR spectrum in the range Ni(2), P(3) and P(4), with an angle between planes of 81.05°.

typical of dinitrogen complexes of 3rd row transition metals.²⁷This near perpendicular arrangement presumably provides the

Both pentane solutions of 5 and solid 5 had strong Raman closest approach of the two nickel fragments (∼4.7 Å) to bind

active stretches at 1908 cm⁻¹. The related dinuclear dinitrogen end-on with dinitrogen, as well as near optimal overlap with

complex [(Cy₃P)₂Ni]₂(μ-N₂) has an IR active N–N stretching fre- the orthogonal π* orbitals on the N₂moiety.

quency at 2028 cm^{−1 26c}

which was suggested to be mono-

,

nuclear species (Cy₃P)₂Ni(η¹-N₂) from dissociation of

a

(Cy₃P)₂Ni moiety from the dinuclear species in toluene.^26aSup-

porting this assignment, a related structurally characterized

mononuclear dinitrogen complex has been reported with an

Complex 5 as a source of (ⁱPr₃P)₂Ni and (ⁱPr₃P)Ni

We have been interested in bond activation reactions that

utilize sources of the (ⁱPr₃P)₂Ni or (ⁱPr₃P)Ni moiety.^3,6c,e,8The

IR stretch at 2072 cm^{−1 28}

Given the similar cone angles of

.

anthracene complex [(ⁱPr₃P)₂Ni]₂(η²-C₁₄H₁₀) is

a capable

i

Cy₃P and Pr₃P, it is not clear why [(Cy₃P)₂Ni]₂(μ-N₂) provides

(Cy₃P)₂Ni(η¹-N₂) in solution whereas there is no sign that 5

converts to (ⁱPr₃P)₂Ni(η¹-N₂) under similar conditions. It may

be that stronger backdonation is occurring from the (ⁱPr₃P)₂Ni

moiety, as this factor often favors dinuclear bridging modes.²⁹

The reduction of (ⁱPr₃P)₂NiX₂(1a) by Mg in THF under a N₂

source,^6cbut has the downside of producing anthracene as a

byproduct, which can be tedious to separate from products

with similar solubilities. Complex 5 is a more versatile source,

in that N₂is readily removed from the reaction mixture.

Complex 5 undergoes an equilibrium reaction with benzene

under an N₂atmosphere. When 5 was dissolved in benzene at

room temperature an additional singlet peak appeared at δ 58

in the ³¹P{¹H} NMR spectrum together with a peak for free

ⁱPr₃P at δ 20.5. Similar observations were made for toluene (δ

59.0), which supports a thermal equilibrium between 5 and a

solvent adduct 6a,b, as shown in eqn (4). In contrast

[(Cy₃P)₂Ni]₂(μ-N₂) was reported to convert to (Cy₃P)₃Ni and

(Cy₃P)Ni;^26athe identity of the latter compound may be worth

reinvestigation.

1

atmosphere also provides 5, as monitored by H, ¹³C{¹H} and

³¹P{¹H} NMR spectroscopy. This is a useful in situ preparation

of 5; however, the product generated in this manner is reluctant

to crystallize from either pentane or hexamethyldisiloxane.

ð3Þ

Recrystallization of saturated solutions of 5 in hexamethyl-

disiloxane at −34 °C aﬀorded red crystals of 5 in form of plates

that were suitable for structural analysis. Repeated recrystalli-

zations provided crystals that index as orthorhombic, but do

not provide a reasonable structure solution in this crystal

system. A solution based on a twinned monoclinic cell was

determined for a partially twinned crystal. Due to the combi-

ð4Þ

i

nation of disorder of some of the Pr₃P substituents and twin-

As monitored by variable-temperature NMR spectroscopy,

more dinitrogen complex was present at low temperature, as

expected for an equilibrium reaction. Attempts to trap the

ⁱPr₃P byproduct that prevented the isolation of 6a,b with Ni-

(COD)₂or Lewis acids were unsuccessful or led to unknown

side products, thus 6a,b were not isolated. Structurally related

examples of related Ni(η⁶-arene) complexes stabilized by phos-

phine, N-heterocyclic carbenes or silylene ligands have been

reported.³⁰The NMR data of the solvent adducts 6a,b are iden-

tical with previous observations of a solvent dependent equili-

brium with the anthracene adduct (ⁱPr₃P)₂Ni(η²-C₁₀H₁₄) in

aromatic solvents.^6cSuch reactivity suggests that in systems

where a single phosphine provides stability, the steric bulk of

ning, the structure is of somewhat low quality, but the N(1)–N(2)

distance of 1.158(5) Å is reasonable for a weakly activated dini-

trogen complex. A depiction of the solid-state molecular struc-

ture is shown in Fig. 1, and X-ray crystallographic collection

and refinement parameters are included in Table 2.

i

the Pr₃P ligand provides an impetus for dissociation. The

chemistry of these precursors can thus be expected to be

diﬀerent from the more thoroughly studied chelating bis

(phosphine)Ni(0) precursors.^28,31

Fig. 1 ORTEP of 5 as determined by X-ray crystallography. Disordered frag-

ments are excluded. Hydrogen atoms are omitted for clarity.

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Table 2 Data and structure reﬁnement parameters for complexes 1–13

1a

1b

1c

2

Empirical formula

F_w

C

₁₈H₄₂P₂Cl₂Ni

C₁₈H₄₂Br₂NiP₂

538.99

C₁₈H₄₂P₂NiI₂

632.97

C₂₀H₄₆NiP₂

407.22

450.07

Cryst syst

a [Å]

b[Å]

c [Å]

Monoclinic

8.2383(16)

8.8394(18)

16.113(3)

90

Monoclinic

8.1476(5)

8.9382(6)

16.3133(10)

90

Orthorhombic

15.249(3)

12.623(3)

25.316(5)

90

Monoclinic

11.7420(3)

13.3060(4)

16.8905(3)

90

α [°]

β [°]

γ [°]

93.70(3)

90

1170.9(4)

P21/c

93.7970(10)

90

1185.41(13)

P21/c

90

116.221(2)

90

2367.40(10)

P21/c

V [Å³]

Space group

Z value

4873.3(17)

Pbca

8

1.725

3.461

173(2)

52.7

2

4

D_calcd.[g cm⁻³

]

1.277

1.192

173(2)

50

1.510

4.323

173(2)

51

1.143

0.954

173(2)

53.4

μ (Mo-Kα) [mm⁻¹

Temperature [K]

2Θ_max[°]

]

Total no. of reflns.

No. unique data reflns; R_int

Abs cor

Transmn factors

No of variables

10 964

11 551

49 168

25 356

2076; 0.0304

Multi-scan

0.76–0.64

112

2240; 0.0246

Multi-scan

0.62–0.47

112

4972; 0.0749

Multi-scan

0.60–0.37

220

5017; 0.0202

Multi-scan

0.89–0.79

236

Reflns/params

18.5

1.081

20.0

1.068

22.6

1.041

21.2

1.069

GOF on F²

R₁; wR₂(I ≥ 2σ)

R₁; wR₂(all data)

Residual density (e−/Å³)

0.0571; 0.1611

0.0623; 0.1673

0.848; −1.446

0.0478; 0.1285

0.0540; 0.13417

1.529; −1.371

0.0347; 0.0678

0.0518; 0.0749

0.882; −0.455

0.0274; 0.0729

0.0299; 0.0751

0.503; −0.306

3a

3b

3c

4

Empirical formula

F_w

C

₁₈H₄₂ClNiP₂

C₁₈H₄₂BrNiP₂

459.08

C₁₈H₄₂INiP₂

506.07

C₁₈H₄₃ClNiP₂

415.62

414.62

Cryst syst

a [Å]

b [Å]

c [Å]

Monoclinic

11.620(2)

13.030(3)

15.806(3)

90

Monoclinic

11.714(2)

13.115(3)

15.899(3)

90

Monoclinic

11.741(2)

13.153(3)

17.089(6)

90

Monoclinic

16.264(3)

8.9520(18)

15.834(3)

90

α [°]

β [°]

γ [°]

106.85(3)

90

2290.4(8)

C2/c

106.94(3)

90

2336.6(8)

C2/c

114.76(2)

90

2396.4(11)

P21/c

93.85(3)

90

2300.2(8)

P21/c

V [Å³]

Space group

Z value

4

D_calcd.[g cm⁻³

]

1.202

1.100

173(2)

52.04

1.305

2.675

173(2)

52

1.403

2.229

173(2)

51

1.200

1.096

173(2)

52.1

μ (Mo-Kα) [mm⁻¹

Temperature [K]

2Θ_max[°]

]

Total no. of reflns.

No. unique data reflns; R_int

Abs cor

Transmn factors

No of variables

11 590

11 892

23 211

23 069

2253; 0.0155

Multi-scan

0.82–0.78

107

2307; 0.0238

Multi-scan

0.96–0.75

107

4480; 0.0255

Multi-scan

0.79–0.50

211

4517; 0.0334

Multi-scan

0.80–0.65

115

Reflns/params

21.1

1.072

21.5

1.117

21.2

1.049

23.1

1.060

GOF on F²

R₁; wR₂(I ≥ 2σ)

R₁; wR₂(all data)

Residual density (e−/Å³)

0.0224; 0.0612

0.0230; 0.0621

0.274; −0.233

0.0270; 0.0738

0.0315; 0.0772

0.590; −0.258

0.0357; 0.0827

0.0408; 0.0865

1.321; −0.496

0.0337; 0.0807

0.0391; 0.0859

0.778; −0.631

5

7

8

9

Empirical formula

F_w

C₃₆H₈₄N₂Ni₂P₂

786.35

C₁₉H₄₂NiO₂P₂

423.18

C₂₀H₄₂Ni O₂P₂

435.19

C₂₀H₄₂Ni₂P₂S₄

590.14

Cryst syst

a [Å]

b [Å]

c [Å]

α [°]

β [°]

Monoclinic

14.950(4)

21.071(5)

15.531(4)

90

114.158(5)

90

Triclinic

Monoclinic

11.660(2)

14.224(3)

15.172(3)

90

111.17(3)

90

Triclinic

7.6433(15)

11.110(2)

17.163(3)

87.22(3)

79.83(3)

71.63(2)

8.1143(3)

8.4650(4)

18.9139(3)

89.3380(10)

77.635(2)

64.2520(10)

1138.11(7)

γ [°]

V [Å³]

4464(2)

2346.4(8)

1361.5(5)

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Table 2 (Contd.)

5

7

8

9

ˉ

Space group

P2(1)/c

4

1.17

1.011

173(2)

50.0

P1

2

C2/c

4

1.232

0.974

173(2)

52.7

P1

2

Z value

D_calcd.[g cm⁻³

]

1.235

1.002

173(2)

52.7

1.440

1.813

173(2)

50

μ (Mo-Kα) [mm⁻¹

Temperature [K]

2Θ_max[°]

]

Total no. of reflns.

No. unique data reflns; R_int

Abs cor

Transmn factors

No of variables

34 028

Twinned

None

—

426

11 781

12 374

13 248

4610; 0.0341

Multi-scan

0.78–0.66

229

2404; 0.0401

Multi-scan

0.95–0.79

120

4779; 0.0863

Multi-scan

0.93–0.65

265

Reflns/params

—

1.244

20.1

1.217

20.0

1.085

18.0

0.981

GOF on F²

R₁; wR₂(I ≥ 2σ)

R₁; wR₂(all data)

Residual density (e−/Å³)

0.094; 0.177

0.138; 0.192

1.276; −1.775

0.0488; 0.0930

0.0600; 0.0996

0.452; −0.277

0.0324; 0.0749

0.0383; 0.0776

0.405; −0.232

0.0579; 0.0934

0.0999; 0.1091

0.590; −0.478

10

11

12

Empirical formula

F_w

C

₄₂H₆₂Ni₂P₄

C₂₄H₄₈P₂SNi

489.33

C₂₀H₄₂P₂S₄Ni₂

590.14

808.22

Cryst syst

a [Å]

b [Å]

c [Å]

Monoclinic

10.8561(5)

17.7577(3)

11.3609(7)

90

Triclinic

9.1831(18)

11.038(2)

13.734(3)

81.49(2)

Triclinic

7.6433(15)

11.110(2)

17.163(3)

87.22(3)

α [°]

β [°]

γ [°]

107.813(3)

90

2085.15(16)

P21/c

88.23(3)

84.88(3)

1371.1(5)

ˉ

P1

79.83(3)

71.63(2)

1361.5(5)

ˉ

P1

V [Å³]

Space group

Z value

2

D_calcd.[g cm⁻³

]

1.287

1.084

173(2)

51.3

1.185

0.908

173(2)

52.04

1.440

1.813

173(2)

50

μ (Mo-Kα) [mm⁻¹

Temperature [K]

2Θ_max[°]

]

Total no. of reflns.

No. unique data reflns; R_int

Abs cor

Transmn factors

No of variables

20 752

14 382

13 248

3959; 0.0221

Multi-scan

0.94–0.64

223

5385; 0.0347

Multi-scan

0.80–0.65

269

4779; 0.0863

Multi-scan

0.93–0.65

265

Reflns/params

17.8

1.159

20.0

1.164

18.0

0.981

GOF on F²

R₁; wR₂(I ≥ 2σ)

R₁; wR₂(all data)

Residual density (e−/Å³)

0.0293; 0.0796

0.0335; 0.0903

0.701; −0.360

0.0387; 0.0951

0.0507; 0.1191

0.547; −0.430

0.0579; 0.0934

0.0999; 0.1091

0.590; −0.478

Stirring a solution of dinitrogen complex 5 in n-pentane

Crystals of (ⁱPr₃P)₂Ni(η²-CO₂) (7) suitable for X-ray diﬀrac-

under an atmosphere of CO₂at −80 °C resulted in the for- tion were grown from a concentrated n-pentane solution at

mation of (ⁱPr₃P)₂Ni(η²-CO₂) (7), as shown in Scheme 2. −34 °C, and an ORTEP representation is shown in Scheme 2.

1

Complex 7 was characterized by H, ³¹P{¹H}, and ¹³C{¹H}NMR The molecular structure is similar to (PCy₃)₂Ni(η²-CO₂),^26b,35

spectroscopy. Its infrared spectrum features a strong ν_(CO)the first structurally characterized CO₂adduct of a transition

band at 1721 cm⁻¹, similar to previously reported (Cy₃P)₂Ni- metal. The uncoordinated C(1)–O(2), bond at 1.211(4) Å is

(CO₂) (1740 cm^{−1 32}and (dtbpe)Ni(CO₂) (1724 cm⁻¹).^31amtypical for a CvO double bond, and the coordinated C(1)–

)

Variable-temperature ³¹P{¹H} NMR spectra were obtained in O(1), bond length of 1.265(4) Å indicates a large degree of

toluene-d₈from 193–293 K and are consistent with a fluxional backbonding from the nickel center into the π* orbital of the

complex. The singlet observed at δ 36.4 decoalesces below ligated CvO unit. The latter distance is significantly longer

2

243 K, and resolves into two doublets, with a J_PPvalue of than the corresponding value of 1.236(1) Å found in a carbon-

38.3 Hz. The estimated free activation energy of the dynamic ate complex [MeC(CH₂PPh₂)₃]Ni(η²-CO₃).³⁶Other four-coordi-

process is 9.5 kcal mol^{−1 33}

At room temperature, the reson- nate nickel CO₂complexes have been reported, but have not

.

ance of the bound CO₂appears as a triplet at δ 157.4 with been crystallographically characterized.^31al,36,37

²J_PC= 13.2 Hz, which supports an intramolecular exchange mech-

A thermal deoxygenation of (ⁱPr₃P)₂Ni(η²-CO₂) (7) under

anism. An intramolecular mechanism has also been postulated refluxing conditions (C₆D₆, 16 h) aﬀorded small amounts

by Aresta et al. for the dynamic complex (Cy₃P)₂Ni(η²-CO₂).³⁴

(ⁱPr₃P)₂Ni(CO)₂(8) and ⁱPr₃PvO, together with unknown

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In the related palladium complexes, the OC–Pd–CO angle of

110.7° is much closer to an ideal tetrahedral angle.³⁹

While from literature precedent with bulky chelating phos-

phines^31amit might be expected that [(ⁱPr₃P)₂Ni]₂N₂(5) would

react with CS₂similarly to CO₂to provide mononuclear

(ⁱPr₃P)₂Ni(η²-CS₂), the NMR data give no hint of such a

product. Both the solution state and solid-state data are con-

sistent with the dinuclear complex [(ⁱPr₃P)Ni(μ-η¹:η²-CS₂)]₂(9),

as shown in Scheme 2, where 5 acts as a source of the (ⁱPr₃P)Ni

moiety. The isolated reaction product has a ³¹P{¹H} NMR

1

spectra with a singlet at δ 45.2. H NMR spectrum shows the

typical resonance pattern for a coordinated ⁱPr₃P ligand.

Coordination of CS₂is indicated in the ³¹C{¹H} NMR spec-

trum, with a signal at δ 125.4.

Crystals of [(ⁱPr₃P)Ni(μ-η¹:η²-CS₂)]₂(9) suitable for X-ray

diﬀraction were grown from a concentrated 5 : 1 toluene–

n-pentane mixture at −34 °C. The molecular structure of one

of two independent molecules in the unit cell of 9 is shown in

Scheme 2. The two (ⁱPr₃P)Ni fragments, which are related by a

crystallographic inversion center, are held together by two CS₂

molecules, so that a six-membered ring is formed. Each CS₂

molecule is η²bonded through a CvS linkage to one metal

atom and σ-bonded to the other nickel through the second

sulfur atom. The coordination environment around each

nickel atom is nearly planar. The metal atom is 0.03 Å out of

the least-squares plane defined by the four ligated atoms. The

chemically diﬀerent C–S bond distances feature similar

lengths, suggestive of extensive π-delocalization. Similar

π-delocalization is also known in other dinuclear CS₂com-

plexes, where only one CvS, group bridges two metal

centers.⁴⁰The C(1)–S(1) bond distance is 1.662(6) Å (average of

the two independent molecules), which is relatively long com-

pared to the C–S distance of 1.61(1) Å in the monomeric

complex (tppme)Ni(CS₂), where tppme = MeC(CH₂PPh₂)₃.⁴¹

The infrared spectrum of 9 shows stretches at 1124 and

662 cm⁻¹, which are similar to the values reported from Hill-

house et al.^31amAn analogue to 9 with Ph₃P as the supporting

phosphine is known,⁴²whose structure was only correctly

assigned after X-ray crystallographic analysis.⁴³

Scheme 2 Reactions of 5 with CO₂, CO, and CS₂. Selected bond distances for

7 (Å): Ni(1)–C(1), 1.842(3); Ni(1)–O(1), 1.932(2); Ni(1)–P(1), 2.2806(9); Ni(1)–P

(2), 2.1412(9); C(1)–O(1), 1.265(4); C(1)–O(2), 1.211(4). Selected bond angles for

7

(°): P(1)–Ni(1)–P(2), 117.98(3); O(1)–Ni(1)–P(1), 102.39(8), C(1)–Ni(1)–P(2),

100.56(11); O(2)–C(1)–O(1), 136.7(4). Selected bond distances for 8 (Å): Ni(1)–

C(1), 1.768(2); Ni(1)–P(1), 2.2370(6); C(1)–O(1), 1.149(2). Selected bond angles

for 8 (°): C(1)–Ni(1)–C(1)*, 119.31(13); P(1)–Ni(1)–P(1)*, 119.60(3); C(1)–Ni(1)–

P(1), 104.56(6). Selected bond distances for 9 (Å): Ni(1)–Ni(1)*, 4.049(12);

Ni(1)–S(1), 2.1648(19); Ni(1)–S(2), 2.1427(18); Ni(1)–C(1), 1.814(6); Ni(1)–P(1),

2.2450(18); C(1)–S(1), 1.662(6); C(1)–S(2)*, 1.660(6). Selected bond angles for 9

(°): C(1)–Ni(1)–S(1), 48.38(18); C(1)–Ni(1)–S(2), 101.89(18); C(1)–Ni(1)–P(1),

158.16(18); S(1)–Ni(1)–P(1), 109.98(7); S(2)–Ni(1)–S(1), 150.15(7); S(2)–Ni(1)–

P(1), 99.85(7).

byproducts, as observed by ³¹P{¹H} NMR. A similar deoxygena-

tion reaction has been reported for the related species (dtbpe)

Ni(CO₂).^31amThe identity of the Ni(0) dicarbonyl 8 was verified

by its independent synthesis from the reaction of 5 and CO

gas, as shown in Scheme 2. Crystals of complex 8 suitable for

solid-state characterization by X-ray crystallography formed

slowly after slow evaporation of concentrated n-pentane sol-

utions over several weeks at 20 °C. X-ray analysis of the crystal-

line material confirmed the dicarbonyl Ni(0) complex 8, and

the solid-state molecular structure is depicted in Scheme 2.

Compound 8 was also characterized by multinuclear NMR

spectroscopy. The room-temperature ¹H NMR spectrum dis-

Complex 5 as a precursor to dinuclear Ni(I) complexes

As shown, complex 5 readily reacts with π-acceptors to act as a

source of either the (ⁱPr₃P)Ni or (ⁱPr₃P)₂Ni fragment, but also

readily reacts with substrates with heteroatom–hydrogen

bonds such as P–H and S–H bonds to access Ni(^I) complexes.

For example, when a stoichiometric amount of diphenylphos-

phine was added to [(ⁱPr₃P)₂Ni]₂N₂(5) in C₆D₆, an immediate

complete conversion to dark brown [(ⁱPr₃P)Ni(μ₂-PPh₂)]₂(10)

was observed by ³¹P{¹H} NMR, as shown in Scheme 3. The

reaction was monitored by ³¹P{¹H} NMR spectroscopy, but

showed no evidence of mononuclear complexes⁴⁴or inter-

mediates arising from oxidative addition. The ³¹P{¹H} NMR

i

plays the typical multiplicity for the Pr₃P ligand. The complex

displays a singlet in the ³¹P{¹H} NMR spectrum at δ 53.4

together and a signal in the ¹³C{¹H} NMR at δ 202.8 for the

coordinated carbonyls. The IR spectrum of 8 shows two very

strong bands of nearly equal intensity at 1987 cm⁻¹and

1926 cm⁻¹for the symmetric and asymmetric CO stretches.

The molecular structure of (ⁱPr₃P)₂Ni(CO)₂(8) and selected

intramolecular bond lengths and angles are given in

Scheme 2. The coordination is very distorted from ideal tetra-

hedral angles, with C(1)–Ni–C(1)* and P(1)–Ni–P(1)* angles of

119.31(13)° and 119.60(3)°, respectively. A similar distortion,

though to a lesser extent, was also noted for (PPh₃)₂Ni(CO)₂.³⁸

i

spectrum features triplet resonances for both the Pr₃P ligands

and the bridging PPh₂ligand at δ 59.7 and 69.5 with coupling

of ²J_PP= 30.7 Hz, consistent with a highly symmetric C_2vNi₂P₄-

core. There was no appearance of a Ni–H stretch in the IR

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distances from 2.17–2.19 Å and approximately D_2hsymmetric

Ni₂P₂cores, complex 10 feature an approximate C_2hcore, with

asymmetric bridging Ni–P distances of 2.0638(5) and 2.2349(5)

Å. The bond lengths suggest the phosphide bridge is behaving

as an X⁻donor to one nickel centre and an L donor to the

other. It is not clear why complex 10 is unique in this regard.

The Ni–Ni bonding distance in 10 is 2.3702(4) Å, which is

appropriate for a Ni–Ni bond.

The addition of a stoichiometric amount of benzenethiol to

a n-pentane solution of [(ⁱPr₃P)₂Ni]₂N₂(5) at −34 °C resulted in

the formation of trans-(ⁱPr₃P)₂Ni(SPh)(H) (11) which slowly

converts to [(ⁱPr₃P)Ni(μ₂-SPh)]₂(12), as shown in Scheme 3.

Complex 11 can be isolated in reasonable yield but is very air-

sensitive. In the ¹H NMR spectrum 11 features a triplet for the

hydride resonance at δ −19.9 with ²J_PH= 45.0 Hz. Confirmation

of the nickel-bound thiophenolato ligand was established by

the change in chemical shift of the phenyl protons, in com-

1

parison to those of free benzenethiol. The H NMR spectrum

and the singlet resonance in the ³¹P{¹H} NMR spectrum at δ

50.9 suggests a square-planar trans-phosphine geometry for

this complex. The ¹H coupled ³¹P NMR spectrum of 11 is a

Scheme 3 Reactions of 4 and 3a leading to dinuclear Ni(I) complexes.

2

resolved doublet splitting with J_PH= 45.0 Hz. The infrared

spectrum of 11 has an intense stretch at 1972 cm⁻¹for ν_Ni–H

,

which is similar to the values reported from related bispho-

sphine Ni–H complexes.^6c,22a,46Oxidative addition of S–H

bonds to nickel have precedent with chelating substrates.⁴⁷

The potential use of this reaction for catalytic S–C bond for-

mation⁴⁸is under investigation.

Slow cooling of n-pentane solutions yielded crystals of 11

suitable for analysis by X-ray diﬀraction. Complex 11 exhibits a

trans square-planar geometry as shown in Fig. 3. The angles

about the nickel atom are distorted from an ideal square-

planar geometry, similar to 4. Steric crowding between the trii-

sopropylphosphine and thiophenolato ligands causes the

phosphines tilted towards the small hydride group with a P(1)–

Ni–P(2) angle of 160.27(3)°. This deviation can be also

observed in the related platinum complex trans-(Cy₃P)₂Pt-

Fig. 2 ORTEP representation of 10 (30% probability ellipsoids) as determined

by X-ray crystallography. Hydrogen atoms are omitted for clarity. The labels (*)

(SCHvS)(H), obtained from insertion of CS₂into

a

indicate atom locations generated by

a crystallographic inversion centre.

Selected bond distances (Å): Ni(1)–Ni(1)*; 2.3702(4); Ni(1)–P(1), 2.0638(5);

Ni(1)–P(1)*, 2.2349(5); Ni(1)–P(2), 2.1440(5). Selected bond angles (°): P(1)*–

Ni(1)–Ni(1)*, 53.152(15); P(1)–Ni(1)–Ni(1)*, 60.064(16); P(1)–Ni(1)–P(2),

124.23(2); P(2)–Ni(1)–Ni(1)*, 173.92(2); P(2)–Ni(1)–P(1)*, 122.353(19); Ni(1)–

P(1)–Ni(1)*, 66.783(16).

spectrum for 10, which is consistent with its formulation as

diphenylphosphido compound.

Complex 10 was isolated by crystallization at −34 °C, and

the dark brown hexagonal plates obtained were suitable for

X-ray crystallographic characterization. A representation of the

solid-state molecular structure is provided in Fig. 2. The mole-

cule possesses a crystallographic center of symmetry at the

midpoint of the Ni–Ni bond. The connectivity of 10 is compar-

able with those of several close analogues;⁴⁵however, a com-

parison of bond lengths reveals a significant diﬀerence.

Whereas all previous related structures have nearly symmetri-

Fig. 3 ORTEP representation of 11 (30% probability ellipsoids) as determined

by X-ray crystallography. Hydrogen atoms, except for the hydridic atom H(1), are

omitted for clarity. Selected bond distances (Å): Ni(1)–H(1), 1.33(4); Ni(1)–S(1),

2.2046(10); Ni(1)–P(1), 2.1721(9); Ni(1)–P(2), 2.2127(9), S(1)–C(1), 1.776(3).

Selected bond angles (°): S(1)–Ni(1)–H(1), 172.7(15); P(1)–Ni(1)–H(1), 80.2(15);

cally bridging PR₂moieties with typical Ni–P single bond P(1)–Ni(1)–P(2), 160.27(3); C(1)–S(1)–Ni(1), 117.13(10).

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Indeed, it was found that compound 12 can be prepared more

easily from the reaction of PhSLi with (ⁱPr₃P)₂NiCl in diethyl

ether, as shown on the bottom of Scheme 3.

Conclusions

Unlike the heavier late transition metals, the chemistry of Ni

complexes supported by ⁱPr₃P donors is relatively poorly

studied. It might be expected that this bulky phosphine might

promote analogous nickel chemistry to the similarly sized

Cy₃P, but with complexes of greater solubility. In fact, there

appears to be significant diﬀerences in chemistry, such as the

fact that the dinitrogen complex [(ⁱPr₃P)₂Ni]₂N₂(5) maintains a

dinuclear structure in pentane, fails to form (ⁱPr₃P)₃Ni, and

has an increased propensity to lose a phosphine donor upon

reaction with a number of reactants. An example is provided

by the equilibrium of 5 in aromatic solvents such as benzene

to provide (ⁱPr₃P)Ni(η⁶-C₆H₆) (6a). Complex 5 provides an entry

into diphosphine Ni(0) adducts such as 7, 8, and 9, as well as

Ni(^II) complexes such as 11 via oxidative addition; however, 5

also provides an entry into Ni(^I) chemistry as well as alternate

oxidation states, as shown in the reactions that provide 10 and

12, as well as previously reported reactivity with silanes.^6e

Fig. 4 ORTEP representation of 12 (30% probability ellipsoids) as determined

by X-ray crystallography. Hydrogen atoms are omitted for clarity. The * labels

indicate atom locations generated by a crystallographic symmetry. Selected

bond distances (Å): Ni(1)–Ni(1)*, 2.3660(10); Ni(1)–S(1), 2.1703(11); Ni(1)–S(1)*,

2.1818(13); Ni(1)–P(1), 2.1734(11). Selected bond angles (°): S(1)–Ni(1)–Ni(1)*,

57.30(4); S(1)–Ni(1)–S(1)*, 114.14(4); P(1)–Ni(1)–Ni(1)*, 173.30(4); Ni(1)–S(1)–

Ni(1)*, 65.86(4).

(Cy₃P)₂PtH₂,⁴⁹as well as other structurally similar hydride

complexes such as 4. The Ni(1)–S(1) distance is 2.2046(10) Å in

11. The Ni(1)–H(1) distance is 1.33(4) Å, though a more accu-

rate bond length determination requires neutron diﬀraction

data.

Solutions of 11 slowly convert within a period of 3 weeks in

n-pentane solutions at room temperature by a dimerization

that involves the loss of dihydrogen and two phosphine

ligands to form [(ⁱPr₃P)Ni(μ₂-SPh)]₂(12), as shown in

i

Steric bulk may play a significant role in the loss of Pr₃P from

complexes containing the (ⁱPr₃P)₂Ni moiety, which may

provide either a kinetic or thermodynamic impetus for the for-

mation of Ni(^I) complexes such as 10 and 12. Complex 3a also

appears to be a useful precursor to Ni(^I) complexes by salt

metathesis. Organometallic dinuclear complexes of the heavier

congeners of Ni have become of interest lately in inert bond

functionalization,⁵⁶and dinuclear Ni(I) complexes also appear

to be of importance in Ni chemistry,⁵⁷including in C–H acti-

vation⁵⁸and C–C coupling reactions.⁸Though many Ni-based

homogeneous catalyst are assumed to proceed through the

0 and +2 oxidation state, there is considerable precedent for

the Ni(^I) oxidation state, and 1-electron processes, and have

been documented in C–F activation,^6fcross-coupling,⁵¹Ziegler

Natta polymerization catalysts,⁵²and the formation of biaryls

from arylnickel(^II) precursors⁵³amongst other catalytic^10q,54

and enzymatic⁵⁹processes. In some cases the use of non-

innocent ligands facilitates 1-electron chemistry,^51j,55though

the formation of 3a–c from 1a–c and 2 suggests that Ni(0)/

Ni(^II) comproportionation to Ni(I) may be common in phos-

phine supported systems. Further studies are under way to

further study the reactivity of 5 as with small molecules and to

demonstrate the eﬀective of 3a as a precursor to Ni(^I) com-

plexes via salt metathesis.

1

Scheme 3. The H NMR spectra of 11 and 12 are very similar,

and the species can be distinguished by the absence of a

hydride resonance in 12 and the upfield shift of the singlet

i

resonance to δ 47.5 for the Pr₃P ligand in the ³¹P{¹H} NMR

spectra. Complex 12 formed green/brown crystals from

n-pentane at −34 °C, and the solid-state structure of 12 was

determined by X-ray crystallography, and is shown in Fig. 4.

The complex features a near coplanar arrangement of the

metal centres and their coordinated ligands. The phenyl sub-

stituents bend away from the plane, suggestive of a stereo-

chemically active non-bonding pair of electrons on the

bridging thiolates. Unlike the Ni–P bond lengths for phos-

phide complex 10, the two Ni–S bonds in 12 are similar, with

bond lengths of 2.1703(11) and 2.1818(13) Å. Species closely

related to 12 have been previously prepared by protonolysis

reactions with Ni(^I) amido precursors.⁵⁰Ni(I) thiolates have

received interest due to their involvement in hydrodesulfuriza-

tion reactions and as models for enzymes.⁵⁰Mononuclear Ni(I)

species have also been obtained from S–H bond oxidative

addition, with proposed dinuclear intermediates that support

a bimolecular mechanism.⁴⁷

General procedures

Complex 3a as a precursor to dinuclear Ni(I) complexes

Unless otherwise stated, all manipulations were performed

Although the reaction of dinitrogen complex 5 with com- under an inert atmosphere of nitrogen using either standard

pounds containing heteroatom-hydrogen bonds is a reason- Schlenk techniques or an MBraun glove-box. Dry, oxygen-free

able synthetic route to Ni(^I) complexes such as 10 and 11, an solvents were employed throughout. Anhydrous pentane,

alternate pathway that obviates the need for highly reactive 5 toluene, and THF were purchased from Aldrich, sparged with

and instead uses its precursor, 3a, would be preferable. dinitrogen, and passed through activated alumina under a

This journal is © The Royal Society of Chemistry 2013

Dalton Trans., 2013, 42, 1461–1475 | 1469

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Dalton Transactions

positive pressure of nitrogen gas; toluene and hexanes were

S^{YNTHESIS AND CHARACTERIZATION OF}2. A mixture of (ⁱPr₃P)₂NiCl₂

further deoxygenated using a Grubbs’ type column system.¹(1a) (2.50 g, 5.55 mmol) and an six fold excess of magnesium

Benzene-d₆was dried by heating at reflux with Na/K alloy in a (740 mg, 30.4 mmol) was combined in 200 mL THF at 20 °C in

sealed vessel under partial pressure then trap-to-trap distilled the presence of 1 atm ethylene atmosphere. After 3 h the dark

and freeze–pump–thaw degassed three times. Toluene-d₈was red mixture turned yellow and all volatiles were removed under

purified in an analogous manner by heating at reflux over Na. vacuum. The product was extracted with n-pentane (2 × 50 mL)

THF-d₈was purified in an analogous manner by heating at and MgCl₂was filtered oﬀ. The product isolated by removing

reflux over K. ¹H, ³¹P{¹H} and ¹³C{¹H}NMR spectra were the n-pentane under vacuum, which provided 2 (1.87 g, 83%)

recorded on a Bruker AMX Spectrometer operating at 300 MHz as a yellow powder in suﬃcient purity for further use. Complex

or 500 MHz with respect to proton nuclei. All chemical shifts 2 crystallized as orange plates and cubes from n-pentane solu-

are recorded in parts per million, and all coupling constants tions at −34 °C. Almost quantitative yields were observed using

are reported in hertz. ¹H NMR spectra were referenced to (ⁱPr₃P)₂NiBr₂(1b) and (ⁱPr₃P)₂NiI₂(1c) in lieu of 1a. Method B:

residual protons (C₆D₅H, δ 7.15; C₇D₇H, δ 2.09; C₄D₇HO, δ A 100 mL Schlenk flask was charged with a 30 mL n-pentane

1.73) with respect to tetramethylsilane at δ 0.00. ³¹P{¹H} NMR solution of 5 (170 mg, 0.216 mmol). The solution was cooled

spectra were referenced to external 85% H₃PO₄at δ 0.00. to −80 °C, and stirred for 5 min under the atmosphere of

¹³C{¹H} NMR spectra were referenced relative to solvent reson- ethylene. The dark red color lightened to yellow-orange

ances (C₆D₆, δ 128.0; C₇D₈, δ 20.4; C₄D₈O, δ 25.37). Infrared immediately. After the solution warmed to ambient tempera-

spectra (IR) were recorded on a Bruker Tensor 27 operating ture, all volatiles were removed under vacuum. The residue was

from 4000–400 cm⁻¹. High Resolution Mass Spectroscopy dissolved in 2 mL n-pentane and crystallized at −34 °C to

1

(HRMS) was performed at McMaster University, Hamilton, aﬀord 161 mg (91%) of 2. H NMR (298 K, C₆D₆, 500 MHz): δ

3

Ontario, Canada. Elemental analyses were performed at the 1.19 (dd, J_PH= 12.0 Hz, J_HH= 7.1 Hz, 36H, P(CH(CH₃)₂)₃),

3

Center for Catalysis and Materials Research, Windsor, Ontario. 2.02 (sept, J_HH= 7.1 Hz, 6H, P(CH(CH₃)₂)₃); 2.06 (s, 4H,

Raman spectra were recorded from on both a Bruker multi- CH₂vCH₂). ¹³C{¹H} NMR (298 K, C₆D₆, 75.5 MHz): δ 20.7 (s,

1

RAM Fourier transform Raman and a Renishaw inVia Raman P(CH(CH₃)₂)₃), 27.1 (vt, J_PC

+

³J_PC= 15.5 Hz, P(CH(CH₃)₂)₃),

2

microscope using 785 nm laser line excitation. The com- 37.1 (vt, J_PC= 12.1 Hz, NiCH₂vCH₂). ³¹P{¹H} NMR (298 K,

pounds benzene-d₆, toluene-d₈, and THF-d₈were purchased C₆D₆, 121.5 MHz): δ 51.8 (s, 2P). IR (Nujol, KBr): 1360 m, 1296

from Cambridge Isotope Laboratory. Magnesium turnings vw, 1241 m, 1183 m, 1157 w, 1090 w, 1051 m, 1028 m, 961 vw,

were vigorously dry stirred over 8 hours to create a reactive 922 w, 880 s, 723 vw, 644, vs, 605 m, 564 m, 523 s, 476 vw,

surface prior to use. Triisopropylphosphine was purchased 449 m, 417 m cm⁻¹. Anal Calcd for C₂₀H₄₆NiP₂(407.22): C,

from STREM and butyl-lithium and lithium triethylborohy- 58.99; H, 11.39; Found C, 58.25; H, 11.14.

dride from Aldrich, and were used without further

purification.

S^{YNTHESIS AND CHARACTERIZATION OF}3A–C. General procedure: To

a heterogeneous mixture of (ⁱPr₃P)₂NiCl₂(1.50 g, 3.33 mmol)

S^YNTHESISAND CHARACTERIZATION OF 1A–C. General procedure: in 50 mL n-pentane, was added 1.1 equivalents of 2 (1.49 g,

A heterogeneous mixture of anhydrous NiX₂(X = Cl, Br, I) 3.66 mmol) at 20 °C. After stirring the mixture for 3 h (30 min

(0.023–0.038 mol, 3–5 g) in 100 mL toluene was stirred in the for 3b, 5 min for 3c) at 20 °C the solvent was removed under

presence of two equivalents of ⁱPr₃P (0.048–0.080 mol, vacuum and the grayish residue washed with 10 mL cold

7.68–12.81 g) in 5% excess. The color of the mixture turned n-pentane (−34 °C) to remove excess 2. The residue of

dark red within a period of 3 days. The mixture was filtered (ⁱPr₃P)₂NiX (X = Cl, Br, I) (3a–c) was taken up in n-pentane at

through a glass frit and the residue washed with 30 mL 20 °C and cooling to −34 °C aﬀorded colorless crystals in a

n-pentane. The toluene was removed under vacuum aﬀording yield of 2.21–2.37 g (80–86%). Recrystallization of concentrated

dark red crystals suitable for X-ray diﬀraction. Combined iso- solutions of 3a–c at −34 °C in n-pentane aﬀorded cubic crystals

lated products aﬀorded (ⁱPr₃P)₂NiX₂(X = Cl, Br, I) (1a–c) in suitable for X-ray diﬀraction. For (ⁱPr₃P)₂NiCl (3a): ¹H NMR

almost quantitative yields. (9.3 g–16.2 g, 90–95% yield). (298 K, C₆D₆, 500 MHz): δ 3.1 (br, 36 H, P(CH(CH₃)₂)₃), 55. (br,

(ⁱPr₃P)₂NiCl₂(1); Anal Calcd for C₁₈H₄₂Cl₂NiP₂(450.07): C, 6H, P(CH(CH₃)₂)₃). Magnetic susceptibility (Evans method,

48.04; H, 9.41; Found C, 47.84; H, 9.81. (ⁱPr₃P)₂NiBr₂(2); IR 298 K, toluene): μ_eﬀ∼ 2.05 μ_B. IR (Nujol, KBr): 1293 w, 1240 s,

(Nujol, KBr): 1294 vw, 1240 s, 1156 m, 1093 m, 1055 s, 1029 s, 1156 m, 1094 m, 1054 s, 1029 s, 963 vw, 924 m, 882 vs, 722 w,

963 vw, 924 m, 881 s, 723 w, 653 vs, 568 m, 517 s, 433 w cm⁻¹

.

655 vs, 600 vw, 569 m, 517 s, 433 w, 411 vw cm⁻¹. Anal Calcd

Anal Calcd for C₁₈H₄₂Br₂NiP₂(538.98): C, 40.11; H, 7.85; for C₁₈H₄₂ClNiP₂(414.62): C, 52.14; H, 10.21; Found C, 52.73;

Found: C, 39.46 H, 8.14. (ⁱPr₃P)₂NiI₂(3): IR (Nujol, KBr): 1385 H, 10.66. For (ⁱPr₃P)₂NiBr (3b): ¹H NMR (298 K, C₆D₆,

s, 1296 m, 1244 s, 1158 m, 1092 m, 1061 s, 1032 s, 963 w, 500 MHz): δ 3.0 (br(s), W_1/2= 170 Hz, P(CH(CH₃)₂)₃); ³¹P{¹H}

927 m, 884 s, 640 vs, 600 m, 522 s, 480 w, 433 w cm⁻¹. Anal NMR (298 K, C₆D₆, 121.5 MHz): no signal. Magnetic suscepti-

Calcd for C₁₈H₄₂I₂NiP₂(632.98): C, 34.15; H, 6.69; Found: C, bility (Evans method, 298 K, toluene): μ_eﬀ∼ 2.14 μ_B. IR (Nujol,

34.30; H, 6.99. ¹H NMR (1a–c) (298 K, C₆D₆, 500 MHz): δ KBr): 1294 vw, 1240 s, 1156 m, 1093 m, 1055 s, 1029 s, 963 vw,

3

1.2–1.4 (d, J_HH= 7.0 Hz, 36H, CH(CH₃)₂), 2.2–2.4 (septet, 924 m, 881 s, 723 w, 653 vs, 568 m, 517 s, 433 w cm⁻¹. Anal

³J_HH= 7.0 Hz, 6H, P(CHMe₂). ¹³C{¹H} NMR (298 K, C₆D₆, Calcd for C₁₈H₄₂BrNiP₂(459.07): C, 47.09; H, 9.22; Found C,

75.5 MHz): δ 20.2 (s, P(CH(CH₃)₂)₃), 23.1 (br s, P(CH(CH₃)₂)₃).

47.21; H, 9.97. For (ⁱPr₃P)₂NiBr (3c): ¹H NMR (298 K, C₆D₆,

1470 | Dalton Trans., 2013, 42, 1461–1475

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500 MHz): δ 2.98 (br(s), W_1/2= 150 Hz, P(CH(CH₃)₂)₃); ³¹P{¹H} N, 2.91. The low nitrogen value may reflect the high reactivity

NMR (298 K, C₆D₆, 121.5 MHz): no signal. Magnetic suscepti- of 5 towards N₂dissociation.

bility (Evans method, 298 K, toluene): μ_eﬀ∼ 2.19 μ_B. IR (Nujol,

KBr): 1295 w, 1240 m, 1156 w, 1092 w, 1056 m, 1029 m, 925 w, B. Dark red 5 (39 mg, 0.5 mmol) was dissolved in n-pentane

881 s, 800 w, 722 w, 652 vs, 608 w, 568 w, 518 s, 432 w cm⁻¹

(0.6 mL) and d₆-benzene or d₈-toluene (0.1 mL) added in a

E^{QUILIBRIUM REACTION OF}5 IN BENZENE OR TOLUENE TO PROVIDE 6A,

.

Anal Calcd for C₁₈H₄₂INiP₂(506.07): C, 42.72; H, 8.37; Found J. Young tube and the sample was analyzed by NMR spec-

C, 42.97; H, 8.49.

troscopy after a period of 5 min. The ³¹P NMR spectra revealed

i

S^YNTHESISAND CHARACTERIZATION OF 4. A solution of 1.0 M a mixture of 6a (or 6b), 5 and Pr₃P in a ratio of (40 : 20 : 40)

LiEt₃BH (0.37 mL, 0.377 mmol) was added dropwise to a respectively. When the deuterated solvent was removed

−34 °C solution of (ⁱPr₃P)₂NiCl₂(170 mg, 0.377 mmol) in THF. in vacuo and dissolved again in n-pentane, 5 is reformed quan-

The dark red solution was warmed to ambient temperature titatively. Detailed NMR data for 6a,b have been previously

within a period of 30 min and removal of THF under vacuum reported.^6c

aﬀorded a brown orange powder. The residue was taken up in

SYNTHESIS AND CHARACTERIZATION OF 7. A solution of 5 (150 mg,

ice-cold n-pentane and filtered through a plug of Celite to 0.191 mmol) in 20 mL n-pentane was exposed to 1 atm 99%

remove (ⁱPr₃P)₂NiCl (3a) as a byproduct. The residue was carbon dioxide at −50 °C. The solution turned immediately

recrystallized from n-pentane at −34 °C and aﬀorded orange from dark red to orange. After stirring for 15 min at room

yellow plates of 4 (40 mg, 25%) suitable for X-ray diﬀraction. temperature the solution was cooled to −78 °C, which caused

Method B: A mixture of stoichiometric amounts of (ⁱPr₃P)₂- the product to slowly precipitate. The solution was decanted

NiCl₂(200 mg, 0.44 mmol) and NaH (10.6 mg, 0.44 mmol) in and the residue taken up in 2 mL ice-cold n-pentane. At

THF was stirred at ambient temperature for 3 h. The solvent −34 °C red crystals (needles) were deposited in a yield of 44%.

3

was removed under vacuum and the residue was extracted with ¹H NMR (298 K, C₆D₆, 500 MHz): δ = 1.05 (dd, J_PH= 13.5 Hz,

3

n-pentane (2 × 10 mL) and filtered through a plug of Celite. ³J_HH= 7.2 Hz, 36H, P(CH(CH₃)₂)₃), 1.75 (sept, J_HH= 7.2 Hz,

The concentrated solution was kept at −34 °C for 30 min and 6H, P(CH(CH₃)₂)₃). ¹³C{¹H} NMR (298 K, C₆D₆, 75.5 MHz): δ

1

3

the precipitate (ⁱPr₃P)₂NiCl (3a) removed from the mother 19.5 (AMM′, J_PC= 19.3 Hz, J_PC= 10.4 Hz, P(CH(CH₃)₂)₃), 24.3

liquor. The n-pentane solution was concentrated and crystal- (vt, ¹J_PC+ ³J_PC= 17.7 Hz, P(CH(CH₃)₂)₃), 157.4 (t, ²J_PC= 13.2 Hz

lized at −34 °C to aﬀord 31 mg (17%) of 5. ¹H NMR (298 K, Ni–CO₂). ³¹P{¹H} NMR (298 K, C₆D₆, 121.5 MHz): δ 49.3 (s, 2P).

2

C₆D₆, 500 MHz): δ −24.3 (t, ²J_PH= 72.0 Hz, 1H, Ni–H), 1.22 (dd, ³¹P{¹H} NMR (193 K, C₆D₆, 121.5 MHz): δ 31.6 (d, J_PP= 38.3

3

2

³J_PH= 12.3 Hz, J_HH= 6.0 Hz, 36H, P(CH(CH₃)₂)₃) 2.03 (sept, Hz, 1P), 63.5 (d, J_PP= 38.3 Hz, 1P). IR (Nujol, KBr): 2039 vw,

³J_HH= 6.0 Hz, 6H, P(CH(CH₃)₂)₃). ³¹P{¹H} NMR (298 K, C₆D₆, 1909 vs, 1721 s, 1670 s, 1239 m, 1181 m, 1154 m, 1092 w,

121.5 MHz): δ 49.5 (s, 2P). IR (Nujol, KBr): 1928 s, 1364 vs, 1044 m, 1025 s, 961 vw, 925 m, 882 s, 832 w, 698 w, 652 vs,

1292 m, 1241 s, 1180 s, 1154 s, 1093 m, 1059 s, 1029 s, 964 vw, 606 m, 544 w, 521 m 475 m. Anal Calcd for C₁₉H₄₂NiO₂P₂

927 m, 884 vs, 799 w, 759 m, 699 m, 658 vs, 618 m, 575 vw, 525 (423.18): C, 53.93; H, 10.00; Found C, 53.85; H 9.87.

s, 477 w, 431 w. Anal Calcd for C₁₈H₄₃ClNiP₂(415.63): C, 52.02;

H, 10.43; Found C, 52.15; H 10.67.

S^YNTHESISAND CHARACTERIZATION OF 8. Complex 5 (157 mg,

0.20 mmol) was dissolved in diethyl ether (10 mL) and cooled

S^{YNTHESIS AND CHARACTERIZATION OF}5. A mixture of (ⁱPr₃P)₂NiCl to −78 °C. The solution was exposed to 1 atm of carbon mon-

(3a) (1.5–2.5 g, 3.6–6.03 mmol) and an excess of magnesium oxide and stirred for 5 min. After the deep red color dis-

(400–850 mg, 16.4–34.9 mmol) were stirred at 20 °C in 20 mL appeared and the reaction mixture reached ambient

THF for 2 h. After the mixture turned blood red the volatiles temperature, the solvent was removed under vacuum and the

were removed under vacuum and extracted with 50 mL grey solid of 8 isolated, washed with ice-cold n-pentane (3 mL)

n-pentane and filtered through a sinter disc with a plug of and dried under vacuum (154 mg, 89% yield). Single crystals

Celite to remove MgCl₂. The solvent was removed under suitable for X-ray diﬀraction of 8 were obtained when concen-

vacuum to provide a dark red, waxy solid (1.10–2.01 g, 78–85% trated n-pentane solutions were recrystallized at 20 °C. ¹H

yield) of 5. Crystals in the form of dark red plates, suitable for NMR (298 K, C₆D₆, 500 MHz): δ 1.13 (dd, ³J_PH= 12.6 Hz, ³J_HH

=

3

X-ray diﬀraction, were isolated from a sample of 50 mg dis- 6.9 Hz, 36H, P(CH(CH₃)₂)₃), 1.75 (sept, J_HH= 6.9 Hz, 6H,

solved in 0.5 mL HMDSO (hexamethyldisiloxane) by cooling to P(CH(CH₃)₂)₃). ¹³C{¹H} NMR (298 K, C₆D₆, 75.5 MHz): δ 19.8

3

−34 °C. ¹H NMR (298 K, C₆D₆, 500 MHz): δ 1.19 (dd, J_PH

=

(s, P(CH(CH₃)₂)₃), 25.9 (vt, ¹J_PC+ ³J_PC= 13.6 Hz, P(CH(CH₃)₂)₃),

202.8 (s(br), Ni–CO). ³¹P{¹H} NMR (298 K, C₆D₆, 121.5 MHz): δ

3

12.0 Hz, J_HH= 7.1 Hz, 72H, P(CH(CH₃)₂)₃) 2.02 (sept, J_HH

7.1 Hz, 12H, P(CH(CH₃)₂)₃). ¹³C{¹H} NMR (298 K, C₆D₆, 53.4 (s, 2P). IR (Nujol, KBr): 1987 vs, 1926 vs, 1302 vw, 1241 m,

1

75.5 MHz): δ 20.7 (s, P(CH(CH₃)₂)₃), 27.1 (vt, J_PC

+

³J_PC

=

1154 w, 1089 m, 1075 w, 1045 w, 1032 s, 961 w, 922 m, 882 s,

16.6 Hz, P(CH(CH₃)₂)₃). ³¹P{¹H} NMR (298 K, C₆D₆, 722 vw, 654 s, 632 s, 591 vs, 501 m, 482 m, 460 s. Anal Calcd

121.5 MHz): δ 43.7 (s, 4P). ¹⁵N{¹H} NMR (298 K, C₅H₁₂, for C₂₀H₄₂NiO₂P₂(435.19): C, 55.20; H, 9.73; Found C, 54.96;

30.5 MHz): δ −71.2 (s(br), W_1/2= 15 Hz, 2N, NiN₂). IR (Nujol, H 10.54.

KBr): 1236 s, 1155 m, 1090 m, 1039 s, 1021 s, 922 m, 880 s, 646

S^{YNTHESIS AND CHARACTERIZATION OF}9. A stirred pentane solution

vs, 601 vs, 545 s, 516 m, 475 s cm⁻¹. Raman (solid and of 5 (180 mg, 0.229 mmol) was cooled to −80 °C and carbon

pentane solution): 1908 cm⁻¹. Anal Calcd for C₃₆H₈₄N₂Ni₂P₄disulfide (34.7 mg, 0.46 mmol) was added in a dropwise

(786.35): C, 54.99; H, 10.77; N, 3.56; Found C, 54.73; H 10.90; fashion. The solution immediately turned orange brown. After

Dalton Trans., 2013, 42, 1461–1475 | 1471

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the solution warmed to ambient temperature, all volatiles were 0.36 mmol) combined with benzenethiol (40 mg, 0.36 mmol)

removed under vacuum and the brownish residue washed with in Et₂O, was added to a stirred diethyl ether solution of

cold n-pentane, dissolved in 5 mL toluene and filtered through 150 mg (ⁱPr₃P)₂NiCl (0.36 mmol) at −34 °C. After 1 h the vola-

a plug of Celite. Red crystals suitable for X-ray diﬀraction tiles were removed in vacuo and the residue extracted with

studies were obtained by recrystallization from a solvent n-pentane (2 × 10 mL) and filtered through a plug of Celite

mixture (toluene–pentane) 5 : 1 at −34 °C. Yield (97 mg, 72%). (113 mg, 48%). Method B: A dark red solution of 5 (90 mg,

3

¹H NMR (298 K, C₆D₆, 500 MHz): δ 1.05 (dd, J_PH= 13.5 Hz, 0.114 mmol) was combined at room temperature with two

3

³J_HH= 7.2 Hz, 36H, P(CH(CH₃)₂)₃), 1.75 (sept, J_HH= 7.2 Hz, equivalents benzenethiol (25 mg, 0.23 mmol) in toluene an

6H, P(CH(CH₃)₂)₃). ¹³C{¹H} NMR (298 K, C₆D₆, 75.5 MHz): δ heated for 16 h at 70 °C. The solvent was removed under

1

19.5 (s, P(CH(CH₃)₂)₃), 23.5 (d, J_PC= 17.3 Hz, P(CH(CH₃)₂)₃), vacuum and upon recrystallization of the remaining oil from

125.4 (s, Ni–CS₂). ³¹P{¹H} NMR (298 K, C₆D₆, 121.5 MHz): δ n-pentane solutions, greenish-brown X-ray quality crystals of

45.2 (s, 2P). IR (Nujol, KBr): 1596 m, 1239 w, 1173 vw, 1124 vs, 12 were obtained (24 mg, 32%). ¹H NMR (298 K, C₆D₆,

3

1056 m, 1028 m, 923 w, 881 m, 721 s, 662 s, 574 w, 526 s. Anal 500 MHz): δ 1.12 (dd, ³J_PH= 13.2 Hz, J_HH= 7.2 Hz, 36H, P(CH

3

Calcd for C₂₀H₄₂Ni₂P₂S₄(590.14): C, 40.70; H, 7.17; Found C, (CH₃)₂)₃), 1.66 (sept, J_HH= 7.2 Hz, 6H, P(CH(CH₃)₂)₃), 6.97

3

4

40.72; H 6.77.

(apparent dd, J_HH= 7.5 Hz, J_HH= 1.5 Hz, 6H, Ar–H), 8.16

3

4

S^{YNTHESIS AND CHARACTERIZATION OF}10. A 110 mg sample of 5 (apparent dd, J_HH= 7.5 Hz, J_HH= 1.5 Hz, 4H, Ar–H). ¹³C{¹H}

(0.14 mmol) was dissolved in 2 mL n-pentane and slowly com- NMR (298 K, C₆D₆, 75.5 MHz): δ 20.1 (s, P(CH(CH₃)₂)₃), 23.8

bined at 25 °C with diphenylphosphine (52 mg, 0.279 mmol) (vt, ¹J_PC+ ³J_PC= 16.7 Hz, P(CH(CH₃)₂)₃), 124.7 (s, Ar–CH), 131.1

in 2 mL n-pentane. After 1 h stirring the solution was dried (s, Ar–CH), 135.7 (s, Ar–CH), 143.1 (s, Ar–C). ³¹P{¹H} NMR

under reduced pressure and the remaining oil dissolved in (298 K, C₆D₆, 121.5 MHz): δ 47.5 (s, 2P). Anal Calcd for C₃₀H₅₂-

1 mL n-pentane. At −34 °C dark brown crystalline hexagonal Ni₂P₂S₂(656.20): C, 54.91; H, 7.99; Found C, 54.81; H 8.04.

1

plates of 10 were formed (88 mg, 78% yield). H NMR (298 K,

C₆D₆, 500 MHz): δ 0.98 (dd, ³J_PH= 13.2 Hz, ³J_HH= 6.9 Hz, 36H,

X-ray crystallography

3

P(CH(CH₃)₂)₃), 1.82 (sept, J_HH= 6.9 Hz, 6H, P(CH(CH₃)₂)₃),

7.02–7.07 (m, 4H, Ar–H), 7.11–7.16 (m, 8H, Ar–H), 7.89–7.95

(m, 8H, Ar–H). ¹³C{¹H} NMR (298 K, C₆D₆, 75.5 MHz): δ 20.1

(s, P(CH(CH₃)₂)₃), 24.8 (vt, ¹J_PC+ ³J_PC= 16.5 Hz, P(CH(CH₃)₂)₃),

The X-ray structures were obtained at low temperature, with

the crystals covered in Paratone and placed rapidly into the

cold N₂stream of the Kryo-Flex low-temperature device. The

data were collected using the SMART⁶⁰software on a Bruker

APEX CCD diﬀractometer using a graphite monochromator

with Mo Kα radiation (λ = 0.71073 Å). A hemisphere of data

was collected using a counting time of 10–30 s per frame. Data

reductions were performed using the SAINT⁶¹software, and

the data were corrected for absorption using SADABS.⁶²The

structures were solved by direct or Patterson’s methods using

SHELXS-97⁶³and refined by full-matrix least-squares on F²

with anisotropic displacement parameters for the non-H

atoms using SHELX-97⁶³and the WinGX⁶⁴software package,

and thermal ellipsoid plots were produced using ORTEP32.⁶⁵

Multiple attempts to collect data on monoclinic 5 were sugges-

tive of a twinned structure, which provides an apparent ortho-

rhombic cell with a = 15.79(2), b = 26.84(4), c = 10.78(2). The

data was modeled as a two component twin. Additional pro-

blems with the data resulted from the disorder of several

donors PⁱPr₃, which were modeled as best as possible. As a

result the structure is of modest quality. Crystallographic.cif

can be obtained from the CCDC (CCDC 896745–896759).

Acknowledgement is made to the Natural Sciences and

Engineering Research Council (NSERC) of Canada for a Dis-

covery Grant for S.A.J. and to the donors of the American

Chemical Society Petroleum Research Fund for partial support

of this research.

2

126.2 (s, Ar–CH), 127.5 (s, Ar–CH), 133.0 (t, J_PC= 6.8 Hz, Ar–

CH), 144.0 (t, J_PC= 9.5 Hz, Ar–C). ³¹P{¹H} NMR (298 K, C₆D₆,

1

121.5 MHz): δ 59.7 (t, ²J_PP= 30.7 Hz, 2P), 69.5 (t, ²J_PP= 30.7 Hz,

2P, NiPPh₂). Anal Calcd for C₄₂H₆₂Ni₂P₄(808.2): C, 62.41; H,

7.73; Found C, 62.73; H, 8.00.

S^{YNTHESIS AND CHARACTERIZATION OF}11. A dark red solution of 5

(150 mg, 0.19 mmol) in 5 mL n-pentane was cooled to −34 °C

and thiophenol (41 mg, 0.38 mmol) was added in dropwise

fashion. The solution lightened to yellow immediately and gas

evolution (N₂) was observed. After the solution warmed to

ambient temperature, the solution was reduced half the

volume and cooled to −34 °C to aﬀord orange crystals of 11

(97 mg, 52%) suitable for X-ray diﬀraction. ¹H NMR (298 K,

2

C₆D₆, 500 MHz): δ = −19.9 (t, J_PH= 45.0 Hz, 1H, Ni–H), 1.21

3

(dd, J_PH= 12.0 Hz, J_HH= 7.1 Hz, 36H, P(CH(CH₃)₂)₃), 1.87

3

(sept, J_HH= 7.1 Hz, 6H, P(CH(CH₃)₂)₃), 7.03 (t, J_HH= 7.1 Hz,

3

1H, Ar–H), 7.14 (t, J_HH= 7.1 Hz, 2H, Ar–H), 7.89 (dd, J_HH

=

4

7.1 Hz, J_HH= 1.2 Hz, 2H, Ar–H), ¹³C{¹H} NMR (298 K, C₆D₆,

1

75.5 MHz): δ 20.7 (s, P(CH(CH₃)₂)₃), 24.9 (vt, J_PC

+ =

³J_PC

21.1 Hz, P(CH(CH₃)₂)₃), 122.1 (s, Ar–CH), 126.8 (s, Ar–CH),

133.3 (s, Ar–CH), 151.8 (t, J_PC= 6.6 Hz, Ar–C) ³¹P{¹H} NMR

3

(298 K, C₆D₆, 121.5 MHz): δ 50.9 (s, 2P). ³¹P NMR (298 K, C₆D₆,

2

121.5 MHz): δ 50.9 (d, J_PH= 45.0 Hz, 2P). IR (Nujol, KBr):

3054 m, 1972 s, 1573 s, 1295 vw, 1253 m, 1157 w, 1082 s,

1051 m, 1022 s, 925 m, 881 m, 762 s, 740 vs, 699 s, 670 vs, 614

vs, 492 m, 447 vw. Anal Calcd for C₂₄H₄₈NiP₂S (489.34): C,

58.91; H, 9.89; Found C, 58.53; H 10.22.

Notes and references

S^YNTHESISAND CHARACTERIZATION OF 12. A solution of PhSiLi,

obtained from a solution of butyl-lithium 1.0 M (0.22 mL,

1 (a) S. Lin and T. Agapie, Synlett, 2011, 1; (b) A. Rudolph and

M. Lautens, Angew. Chem., Int. Ed., 2009, 48, 2656;

1472 | Dalton Trans., 2013, 42, 1461–1475

View Article Online

Dalton Transactions

Paper

(c) J. Terao and N. Kambe, Acc. Chem. Res., 2008, 41, 1545;

(d) M. R. Netherton and G. C. Fu, Adv. Synth. Catal., 2004,

346, 1525; (e) D. J. Cardenas, Angew. Chem., Int. Ed., 2003,

42, 384; (f) A. Yamamoto, J. Organomet. Chem., 2002, 653,

5; (g) J. J. Hirner and S. A. Blum, Organometallics, 2011, 30,

1299.

2 (a) S. A. Johnson, J. A. Hatnean and M. E. Doster, Prog.

Inorg. Chem., 2012, 57, 255; (b) P. Alvarez-Bercedo and

R. Martin, J. Am. Chem. Soc., 2010, 132, 17352; (c) P. Kelley,

S. Lin, G. Edouard, M. W. Day and T. Agapie, J. Am. Chem.

Soc., 2012, 134, 5480; (d) A. R. Ehle, Q. Zhou and

M. P. Watson, Org. Lett., 2012, 14, 1202; (e) A. G. Sergeev

and J. F. Hartwig, Science, 2011, 332, 439; (f) K. Muto,

J. Yamaguchi and K. Itami, J. Am. Chem. Soc., 2012, 134,

169.

Struct. Commun., 2000, 56, 1067; (f) M. Valente, C. Freire

and B. de Castro, J. Chem. Soc., Dalton Trans., 1998, 1557;

(g) V. V. Saraev, P. B. Kraikivskii, I. Svoboda, A. S. Kuzakov

and R. F. Jordan, J. Phys. Chem. A, 2008, 112, 12449;

(h) P. B. Kraikivskii, V. V. Saraev, P. G. Lazarev,

G. Myagmarsuren, V. S. Tkach and F. K. Shmidt, Koord.

Khim., 1996, 22, 508; (i) E. R. Burkhardt, R. G. Bergman

and C. H. Heathcock, Organometallics, 1990, 9, 30;

( j) P. Chmielewski, M. Grzeszczuk, L. Latos-Grazynski and

J. Lisowski, Inorg. Chem., 1989, 28, 3546; (k) F. M. Dayrit

and J. Schwartz, J. Am. Chem. Soc., 1981, 103, 4466;

(l) E. K. Barefield, D. A. Krost, D. S. Edwards, D. G. Van

Derv, R. L. Trytko, S. P. O’Rear and A. N. Williamson, J. Am.

Chem. Soc., 1981, 103, 6219; (m) P. Dapporto and

L. Sacconi, Inorg. Chim. Acta, 1980, 39, 61; (n) A. Bencini,

C. Benelli, D. Gatteschi and L. Sacconi, Inorg. Chim. Acta,

1979, 37, 195; (o) F. Caballero, M. Gómez and P. Royo,

Transition Met. Chem., 1977, 2, 130; (p) R. Barbucci,

A. Bencini and D. Gatteschi, Inorg. Chem., 1977, 16, 2117;

(q) T. Fujihara, K. Nogi, T. Xu, J. Terao and Y. Tsuji, J. Am.

Chem. Soc., 2012, 134, 9106; (r) F. Scott, C. Krueger and

P. Betz, J. Organomet. Chem., 1990, 387, 113.

3 (a) M. E. Doster, J. A. Hatnean, T. Jeftic, S. Modi and

S. A. Johnson, J. Am. Chem. Soc., 2010, 132, 11923;

(b) S. A. Johnson, M. E. Doster, J. Matthews, M. Shoshani,

M. Thibodeau, A. Labadie and J. A. Hatnean, Dalton Trans.,

2012, 8135.

4 A. D. Sun and J. A. Love, Dalton Trans., 2010, 10362.

5 (a) T. M. Goegsig, J. Kleimark, S. O. Nilsson Lill,

S. Korsager, A. T. Lindhardt, P.-O. Norrby and 11 (a) G. Bontempelli, F. Magno, B. Corain and G. Schiavon,

T. Skrydstrup, J. Am. Chem. Soc., 2012, 134, 443;

(b) G. P. McGlacken and S. L. Clarke, ChemCatChem, 2011,

3, 1260; (c) B. M. Rosen, K. W. Quasdorf, D. A. Wilson,

N. Zhang, A.-M. Resmerita, N. K. Garg and V. Percec, Chem.

Rev., 2011, 111, 1346; (d) M. Tobisu and N. Chatani, Chem-

CatChem, 2011, 3, 1410; (e) M. Tobisu, K. Yamakawa,

T. Shimasaki and N. Chatani, Chem. Commun., 2011, 2946.

Inorg. Chim. Acta, 1985, 99, 19; (b) G. A. Bowmaker and

J. P. Williams, J. Chem. Soc., Dalton Trans., 1994, 1231;

(c) V. V. Saraev, P. B. Kraikivskii, S. N. Zelinskii,

G. V. Ratovskii, V. S. Tkach and F. K. Shmidt, Koord. Khim.,

2001, 27, 757; (d) V. Saraev, P. Kraikivskii, S. Zelinskii,

A. Vil’ms, D. Matveev, A. Yunda, A. Fedonina and

K. Lammertsma, Koord. Khim., 2006, 32, 397.

6 (a) S. A. Johnson, C. W. Huﬀ, F. Mustafa and M. Saliba, 12 (a) A. Turco and G. Giacometti, Ricerca Sci., 1959, 29, 1057;

J. Am. Chem. Soc., 2008, 130, 17278; (b) S. A. Johnson,

E. T. Taylor and S. J. Cruise, Organometallics, 2009, 28, 3842;

(b) T. Saito, H. Munakata and H. Imoto, Inorg. Synth., 1977,

17, 83.

(c) J. A. Hatnean, R. Beck, J. D. Borrelli and S. A. Johnson, 13 (a) M. Capka and J. Hetflejs, Collect. Czech. Chem.

Organometallics, 2010, 29, 6077; (d) S. A. Johnson,

N. M. Mroz, R. Valdizon and S. Murray, Organometallics,

Commun., 1975, 40, 2073; (b) N. M. Doherty and

N. W. Hoﬀmann, Chem. Rev., 1991, 91, 553.

2011, 30, 441; (e) R. Beck and S. A. Johnson, Organometallics, 14 H. Wunderlich, Z. Kristallogr., 1997, 212, 381.

2012, 31, 3599; (f) J. A. Hatnean and S. A. Johnson, Organo- 15 K. R. Poerschke, J. Am. Chem. Soc., 1989, 111, 5691.

metallics, 2012, 31, 1361.

7 F. H. Allen, Acta Crystallogr., Sect. B: Struct. Sci., 2002, 58,

380.

16 (a) C. Karunatilaka, B. S. Tackett, J. Washington and

S. G. Kukolich, J. Am. Chem. Soc., 2007, 129, 10522;

(b) E. D. Jemmis, B. Pathak, R. B. King and H. F. Schaefer

Iii, Chem. Commun., 2006, 2164.

8 R. Beck and S. A. Johnson, Chem. Commun., 2011, 9233.

9 (a) L. Porri, M. C. Gallazzi and G. Vitulli, Chem. Commun., 17 W. Scherer, G. Eickerling, D. Shorokhov, E. Gullo,

1967, 228; (b) H. Lehmkuhl, K. Mehler and G. Hauschild, G. S. McGrady and P. Sirsch, New J. Chem., 2006, 30, 309.

Chem. Ber., 1983, 116, 438; (c) J. M. Cassidy and 18 W. Dreissig and H. Dietrich, Acta Crystallogr., Sect. B:

K. H. Whitmire, Acta Crystallogr., Sect. C: Cryst. Struct.

Commun., 1991, 47, 2094.

Struct. Sci., 1981, 37, 931.

19 P. Heimbach, Angew. Chem., 1964, 76, 586.

10 (a) P. Stoppioni, A. Biliotti and R. Morassi, J. Organomet. 20 D. J. Mindiola, R. Waterman, D. M. Jenkins and

Chem., 1982, 236, 119; (b) J. Langer, R. Fischer, H. Görls, G. L. Hillhouse, Inorg. Chim. Acta, 2003, 345, 299.

N. Theyssen and D. Walther, Z. Anorg. Allg. Chem., 2007, 21 V. V. Saraev, B. Ri, F. K. Shmidt and G. M. Larin, Koord.

633, 557; (c) C. A. Ghilardi, C. Mealli, S. Midollini, Khim., 1982, 8, 1485.

A. Orlandini, D. M. Proserpio, A. Cinquantini and 22 (a) A. L. Seligson, R. L. Cowan and W. C. Trogler, Inorg.

P. Zanello, Struct. Chem., 1990, 1, 441; (d) N. C. Norman,

A. G. Orpen, M. J. Quayle and G. R. Whittell, Acta Crystal-

logr., Sect. C: Cryst. Struct. Commun., 2002, 58, m160;

(e) D. D. Ellis and A. L. Spek, Acta Crystallogr., Sect. C: Cryst.

Chem., 1991, 30, 3371; (b) M. L. H. Green, T. Saito and

P. J. Tanfield, J. Chem. Soc. A, 1971, 152; (c) M. L. H. Green,

H. Munakata and T. Saito, J. Chem. Soc., Chem. Commun.,

1969, 1287a.

Dalton Trans., 2013, 42, 1461–1475 | 1473

View Article Online

Paper

Dalton Transactions

23 (a) U. Müller, W. Keim, C. Krüger and P. Betz, Angew.

Chem., Int. Ed., 1989, 28, 1011; (b) N. D. Clement,

K. J. Cavell, C. Jones and C. J. Elsevier, Angew. Chem., Int.

Ed., 2004, 43, 1277; (c) P. L. Holland, M. E. Smith,

R. A. Andersen and R. G. Bergman, J. Am. Chem. Soc., 1997,

119, 12815; (d) All database searches and analyses were done

using the ConQuest and Vista programs associated with Cam-

bridge Structural Database (CSD) v5.24, and ConQuest version

1.6.; (e) I. J. Bruno, J. C. Cole, P. R. Edgington, M. Kessler,

C. F. Macrae, P. McCabe, J. Pearson and R. Taylor, Acta

Crystallogr., Sect. B: Struct. Sci., 2002, 58, 389.

(n) J. J. Garcia, A. Arevalo, N. M. Brunkan and W. D. Jones,

Organometallics, 2004, 23, 3997; (o) J. J. Garcia,

N. M. Brunkan and W. D. Jones, J. Am. Chem. Soc., 2002,

124, 9547; (p) J. J. Garcia and W. D. Jones, Organometallics,

2000, 19, 5544; (q) J. J. Garcia, P. Zerecero-Silva, G. Reyes-

Rios, M. G. Crestani, A. Arevalo and R. Barrios-Francisco,

Chem. Commun., 2011, 10121; (r) M. R. Grochowski, T. Li,

W. W. Brennessel and W. D. Jones, J. Am. Chem. Soc., 2010,

132, 12412; (s) A. L. Iglesias and J. J. Garcia, J. Mol. Catal. A:

Chem., 2009, 298, 51; (t) A. L. Iglesias, M. Munoz-

Hernandez and J. J. Garcia, J. Organomet. Chem., 2007, 692,

3498; (u) J. Jacob and W. D. Jones, J. Org. Chem., 2003, 68,

3563; (v) T. Li, J. J. Garcia, W. W. Brennessel and

W. D. Jones, Organometallics, 2010, 29, 2430; (w) S. S. Oster,

R. J. Lachicotte and W. D. Jones, Inorg. Chim. Acta, 2002,

330, 118; (x) A. Oviedo, J. Torres-Nieto, A. Arevalo and

J. J. Garcia, J. Mol. Catal. A: Chem., 2008, 293, 65;

(y) A. Reyes-Sanchez, F. Canavera-Buelvas, R. Barrios-

Francisco, O. L. Cifuentes-Vaca, M. Flores-Alamo and

J. J. Garcia, Organometallics, 2011, 30, 3340; (z) F. Scott,

S. Afr. J. Chem., 1990, 43, 72; (aa) E. E. Smith, G.-D. Du,

P. E. Fanwick and M. M. Abu-Omar, Organometallics, 2010,

29, 6527; (ab) B. D. Swartz, N. M. Reinartz,

W. W. Brennessel, J. J. Garcia and W. D. Jones, J. Am. Chem.

Soc., 2008, 130, 8548; (ac) J. Torres-Nieto, A. Arevalo and

J. J. Garcia, Organometallics, 2007, 26, 2228; (ad) J. Torres-

Nieto, A. Arevalo, P. Garcia-Gutierrez, A. Acosta-Ramirez

and J. J. Garcia, Organometallics, 2004, 23, 4534;

(ae) D. A. Vicic and W. D. Jones, J. Am. Chem. Soc., 1997,

119, 10855; (af) D. A. Vicic and W. D. Jones, Organometal-

lics, 1998, 17, 3411; (ag) D. A. Vicic and W. D. Jones, J. Am.

Chem. Soc., 1999, 121, 7606; (ah) D. A. Vicic and

W. D. Jones, J. Am. Chem. Soc., 1999, 121, 4070;

(ai) P. Zerecero-Silva, I. Jimenez-Solar, M. G. Crestani,

A. Arevalo, R. Barrios-Francisco and J. J. Garcia, Appl.

Catal., A, 2009, 363, 230; (aj) J. Torres-Nieto,

W. W. Brennessel, W. D. Jones and J. J. Garcia, J. Am. Chem.

Soc., 2009, 131, 4120; (ak) C. Flener Lovitt, G. Frenking and

G. S. Girolami, Organometallics, 2012, 31, 4122;

(al) L. Gonzalez-Sebastian, M. Flores-Alamo and

J. J. Garcia, Dalton Trans., 2011, 9116; (am) J. S. Anderson,

V. M. Iluc and G. L. Hillhouse, Inorg. Chem., 2010, 49,

10203; (an) V. M. Iluc and G. L. Hillhouse, Tetrahedron,

2006, 62, 7577; (ao) V. M. Iluc and G. L. Hillhouse, J. Am.

Chem. Soc., 2010, 132, 11890; (ap) V. M. Iluc,

C. A. Laskowski, C. K. Brozek, N. D. Harrold and

G. L. Hillhouse, Inorg. Chem., 2010, 49, 6817;

(aq) V. M. Iluc, A. J. M. Miller, J. S. Anderson,

M. J. Monreal, M. P. Mehn and G. L. Hillhouse, J. Am.

Chem. Soc., 2011, 133, 13055; (ar) V. M. Iluc, A. J. M. Miller

and G. L. Hillhouse, Chem. Commun., 2005, 5091;

(as) R. Waterman and G. L. Hillhouse, J. Am. Chem. Soc.,

2008, 130, 12628.

24 (a) M. B. Hursthouse, K. J. Izod, M. Motevallim and

P. Thornton, Polyhedron, 1994, 13, 151; (b) C. S. Cundy,

J. Organomet. Chem., 1974, 69, 305.

25 C. A. Tolman, Chem. Rev., 1977, 77, 313.

26 (a) P. W. Jolly, K. Jonas, C. Krüger and Y. H. Tsay, J. Organo-

met. Chem., 1971, 33, 109; (b) M. Aresta, C. F. Nobile,

V. G. Albano, E. Forni and M. Manassero, J. Chem. Soc.,

Chem. Commun., 1975, 636; (c) M. Aresta, C. F. Nobile and

A. Sacco, Inorg. Chim. Acta, 1975, 12, 167.

27 (a) A. R. Fout, F. Basuli, H. Fan, J. Tomaszewski,

J. C. Huﬀman, M.-H. Baik and D. J. Mindiola, Angew.

Chem., Int. Ed., 2006, 45, 3291; (b) T. A. Betley and

J. C. Peters, J. Am. Chem. Soc., 2003, 125, 10782.

28 R. Waterman and G. L. Hillhouse, Can. J. Chem., 2005, 83,

328.

29 M. D. Fryzuk and S. A. Johnson, Coord. Chem. Rev., 2000,

200–202, 379.

30 (a) A. Meltzer, C. Präsang, C. Milsmann and M. Driess,

Angew. Chem., Int. Ed., 2009, 48, 3170; (b) C. H. Lee,

D. S. Laitar, P. Mueller and J. P. Sadighi, J. Am. Chem. Soc.,

2007, 129, 13802; (c) T. Nickel, R. Goddard, C. Krüger and

K.-R. Pörschke, Angew. Chem., Int. Ed., 1994, 33, 879.

31 (a) I. Bach, R. Goddard, C. Kopiske, K. Seevogel and

K.-R. Poerschke, Organometallics, 1999, 18, 10;

(b) T. J. Anderson and D. A. Vicic, Organometallics, 2004,

23, 623; (c) T. A. Atesin, T. Li, S. Lachaize,

W. W. Brennessel, J. J. Garcia and W. D. Jones, J. Am. Chem.

Soc., 2007, 129, 7562; (d) T. A. Atesin, T. Li, S. Lachaize,

J. J. Garcia and W. D. Jones, Organometallics, 2008, 27,

3811; (e) N. M. Brunkan, D. M. Brestensky and W. D. Jones,

J. Am. Chem. Soc., 2004, 126, 3627; (f) N. M. Brunkan and

W. D. Jones, J. Organomet. Chem., 2003, 683, 77;

(g) M. G. Crestani, A. Arevalo and J. J. Garcia, Adv. Synth.

Catal., 2006, 348, 732; (h) M. G. Crestani and J. J. Garcia,

J. Mol. Catal. A: Chem., 2009, 299, 26; (i) M. G. Crestani,

M. Munoz-Hernandez, A. Arevalo, A. Acosta-Ramirez and

J. J. Garcia, J. Am. Chem. Soc., 2005, 127, 18066;

( j) C. Crisostomo, M. G. Crestani and J. J. Garcia, J. Mol.

Catal. A: Chem., 2007, 266, 139; (k) C. Crisostomo,

M. G. Crestani and J. J. Garcia, Inorg. Chim. Acta, 2010, 363,

1092; (l) B. L. Edelbach, D. A. Vicic, R. J. Lachicotte and

W. D. Jones, Organometallics, 1998, 17, 4784; (m) A. Flores-

Gaspar, P. Pinedo-Gonzalez, M. G. Crestani, M. Munoz- 32 M. Aresta and C. F. Nobile, J. Chem. Soc., Dalton Trans.,

Hernandez, D. Morales-Morales, B. A. Warsop, W. D. Jones 1977, 708.

and J. J. Garcia, J. Mol. Catal. A: Chem., 2009, 309, 1; 33 H. J. Reich, J. Chem. Educ., 1995, 72, 1086.

1474 | Dalton Trans., 2013, 42, 1461–1475

View Article Online

Dalton Transactions

Paper

34 M. Aresta, R. Gobetto, E. Quaranta and I. Tommasi, Inorg.

Chem., 1992, 31, 4286.

35 A. Doehring, P. W. Jolly, C. Kruger and M. J. Romao,

Z. Naturforsch. B, 1985, 40, 484.

36 C. Bianchini, C. Mealli, A. Meli and M. Sabat, Inorg. Chem.,

1984, 23, 2731.

37 H. Hoberg, A. Ballesteros and A. Sigan, J. Organomet.

Chem., 1991, 403, C19.

S. B. Harkins, R. Scopelliti and X. Hu, J. Am. Chem. Soc.,

2008, 130, 8156; (f) O. Vechorkin, V. Proust and X. Hu,

J. Am. Chem. Soc., 2009, 131, 9756; (g) S. Miyazaki, Y. Koga,

T. Matsumoto and K. Matsubara, Chem. Commun., 2010,

46, 1932; (h) K. Zhang, M. Conda-Sheridan, S. R. Cooke and

J. Louie, Organometallics, 2011, 30, 2546; (i) G. D. Jones,

C. McFarland, T. J. Anderson and D. A. Vicic, Chem.

Commun., 2005, 4211; ( j) G. D. Jones, J. L. Martin,

C. McFarland, O. R. Allen, R. E. Hall, A. D. Haley,

R. J. Brandon, T. Kanovalova, P. J. Desrochers, P. Pulay and

D. A. Vicic, J. Am. Chem. Soc., 2006, 128, 13175.

38 J. Moncol, M. Gembicky and P. Coppens, Acta Crystallogr.,

Sect. E: Struct. Rep. Online, 2004, 60, m1582.

39 R. Trebbe, R. Goddard, A. Rufińska, K. Seevogel and

K.-R. Pörschke, Organometallics, 1999, 18, 2466.

40 (a) M. A. Bennett, J. A. Johnson and A. C. Willis, Organo-

metallics, 1996, 15, 68; (b) T. Yamamoto, T. Kohara,

K. Osakada and A. Yamamoto, Bull. Chem. Soc. Jpn., 1983,

56, 2147.

41 C. Bianchini, D. Masi, C. C. Mealli and A. Meli, Inorg.

Chem., 1984, 23, 2838.

42 (a) M. C. Baird and G. Wilkinson, J. Chem. Soc. A, 1967,

865; (b) E. Uhlig and W. Poppitz, Z. Chem., 1979, 19, 191;

(c) J. A. Ibers, Chem. Soc. Rev., 1982, 11, 57.

52 (a) V. V. Saraev, P. B. Kraikivskii, S. N. Zelinskiy,

D. A. Matveev, A. I. Vilms, A. V. Rohin and K. Lammertsma,

J. Mol. Catal. A: Chem., 2005, 236, 125; (b) V. V. Saraev,

F. K. Shmidt, G. M. Larin, V. S. Tkach and V. G. Lipovich,

Russ. Chem. Bull., 1974, 23, 2549; (c) A. N. Nesmeyanov,

L. S. Isaeva, L. N. Morozova, P. V. Petrovskii,

B. L. Tumanskii, B. V. Lokshin and Z. S. Klemenkova, Inorg.

Chim. Acta, 1980, 43, 1; (d) J. G. van Ommen, J. G. M. van

Rens and P. J. Gellings, J. Mol. Catal., 1981, 13, 313.

53 T. T. Tsou and J. K. Kochi, J. Am. Chem. Soc., 1979, 101,

7547.

43 C. Bianchini, C. A. Ghilardi, A. Meli, S. Midollini and

A. Orlandini, J. Chem. Soc., Chem. Commun., 1983, 753.

44 R. Melenkivitz, D. J. Mindiola and G. L. Hillhouse, J. Am.

Chem. Soc., 2002, 124, 3846.

54 Y. Y. Otman, O. S. Manulik and V. R. Flid, Kinet. Catal.,

2008, 49, 479.

55 T. J. Anderson, G. D. Jones and D. A. Vicic, J. Am. Chem.

Soc., 2004, 126, 8100.

45 (a) C. E. Kriley, C. J. Woolley, M. K. Krepps, E. M. Popa,

P. E. Fanwick and I. P. Rothwell, Inorg. Chim. Acta, 2000, 56 (a) N. R. Deprez and M. S. Sanford, J. Am. Chem. Soc., 2009,

300–302, 200; (b) R. A. Jones, A. L. Stuart, J. L. Atwood,

W. E. Hunter and R. D. Rogers, Organometallics, 1982, 1,

1721; (c) B. Deppisch and H. Schaefer, Z. Anorg. Allg.

Chem., 1982, 490, 129.

131, 11234; (b) D. C. Powers and T. Ritter, Nat. Chem., 2009,

1, 302; (c) D. C. Powers, D. Y. Xiao, M. A. L. Geibel and

T. Ritter, J. Am. Chem. Soc., 2010, 132, 14530.

57 (a) T. V. V. Ramakrishna and P. R. Sharp, Organometallics,

2004, 23, 3079; (b) J. J. Eisch, A. M. Piotrowski, K. I. Han,

C. Kruger and Y. H. Tsay, Organometallics, 1985, 4, 224.

58 (a) A. L. Keen, M. Doster and S. A. Johnson, J. Am. Chem.

Soc., 2007, 129, 810; (b) A. L. Keen and S. A. Johnson, J. Am.

Chem. Soc., 2006, 128, 1806.

59 C. Finazzo, J. Harmer, C. Bauer, B. Jaun, E. C. Duin,

F. Mahlert, M. Goenrich, R. K. Thauer, S. Van Doorslaer

and A. Schweiger, J. Am. Chem. Soc., 2003, 125, 4988.

46 M. Aresta, E. Quaranta, A. Dibenedetto, P. Giannoccaro,

I. Tommasi, M. Lanfranchi and A. Tiripicchio, Organo-

metallics, 1997, 16, 834.

47 P. B. Kraikivskii, M. Frey, H. A. Bennour, A. Gembus,

R. Hauptmann, I. Svoboda, H. Fuess, V. V. Saraev and

H.-F. Klein, J. Organomet. Chem., 2009, 694, 1869.

48 P. Bichler and J. A. Love, Top. Organmet. Chem., 2010, 31,

39.

49 A. Albinati, A. Musco, G. Carturan and G. Strukul, Inorg. 60 SMART, Molecular Analysis Research Tool, Bruker AXS Inc.,

Chim. Acta, 1976, 18, 219. Madison, WI, 2001.

50 M. Ito, T. Matsumoto and K. Tatsumi, Inorg. Chem., 2009, 61 SAINTPlus, Data Reduction and Correction Program, Bruker

48, 2215. AXS Inc., Madison, WI, 2001.

51 (a) D. G. Morrell and J. K. Kochi, J. Am. Chem. Soc., 1975, 62 SADABS, An Empirical Absorption Correction Program, Bruker

97, 7262; (b) I. Colon and D. R. Kelsey, J. Org. Chem., 1986, AXS Inc, Madison, WI, 2001.

51, 2627; (c) A. Klein, Y. H. Budnikova and O. G. Sinyashin, 63 G. Sheldrick, Acta Crystallogr., Sect. A: Found. Crystallogr.,

J. Organomet. Chem., 2007, 692, 3156; (d) V. B. Phapale, 2008, 64, 112.

E. Bunuel, M. Garcia-Iglesias and D. J. Cardenas, Angew. 64 L. Farrugia, J. Appl. Crystallogr., 1999, 32, 837.

Chem., Int. Ed., 2007, 46, 8790; (e) Z. Csok, O. Vechorkin, 65 L. Farrugia, J. Appl. Crystallogr., 1997, 30, 565.

Dalton Trans., 2013, 42, 1461–1475 | 1475

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Synthesis and chemistry of bis(triisopropylphosphine) nickel(i) and nickel(0) precursors

DOI: 10.1039/c2dt32008h

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Article abstract of DOI:10.1039/c2dt32008h

Full text of DOI:10.1039/c2dt32008h

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