Lewis acid assisted methyl/chlorine exchange in silylated hydrazinochlorophosphanes

Article abstract of DOI:10.1021/ic200005q

Differently substituted hydrazinophosphanes of the type (Me ₃Si)₂N-N(SiMe₃)-PR¹R² (R¹ = Cl withR² = Me, C₆F₅ and R¹ =Me, R² = C_6<

Full text of DOI:10.1021/ic200005q

ARTICLE
pubs.acs.org/IC
Lewis Acid Assisted Methyl/Chlorine Exchange in Silylated
Hydrazinochlorophosphanes
Andrea Westenkirchner,†,§ Alexander Villinger,† Konstantin Karaghiosoff,§ Ronald Wustrack,†
Dirk Michalik,‡ and Axel Schulz*,†,‡
†Institut f€ur Chemie, Abteilung Anorganische Chemie, Universit€at Rostock, Albert-Einstein-Strasse 3a, 18059 Rostock, Germany
‡Leibniz-Institut f€ur Katalyse e.V. an der Universit€at Rostock, Albert-Einstein-Strasse 29a, 18059 Rostock, Germany
§Ludwig-Maximillians Universit€at M€unchen, Department of Chemistry, Ludwig-Maximilians University (LMU),
Butenandtstrasse 5-13 (Haus D), D-81377 Munich, Germany
S Supporting Information
b
ABSTRACT: Differently substituted hydrazinophosphanes of
the type (Me3Si)2N-N(SiMe3)-PR1R2 (R1 = Cl with R2 = Me,
C6F5 and R1 = Me, R2 = C6H5) have been studied in the reaction
with Lewis acids such as ECl3 (E = Al, Ga). For (Me3Si)2N-
N(SiMe3)-P(Cl)(Me) and(Me3Si)2N-N(SiMe3)-P(Me)(C6H5), only adduct formation was found while a chlorine/methyl exchange
reaction was observed for (Me3Si)2N-N(SiMe3)-P(Cl)R (R = C6H5 and C6F5) leading to the formation of (Me2ClSi)(Me3Si)N-
N(SiMe3)-P(Me)R, which crystallize as ECl3 adducts. The free hydrazinophosphanes can be obtained by removal of the Lewis acid with
the help of a strong base such as 4-(dimethylamino)pyridine (DMAP).
’ INTRODUCTION
yielded also a triazadiphosphole (RN3P2, R = Mes*).9 The first
tetrazaphosphole8 RN4P (R = Mes*) was also obtained by a GaCl3-
assisted [3 þ 2] cycloaddition of Mes*—NdP—Cl with Me3Si-
N3. The same reaction with the heavier arsenic analog led to the first
tetrazarsole.11 All studied GaCl3-assisted [3 þ 2] cycloadditions are
fast, high-yielding (>90%), and clean reactions. These cyclizations
can be carried out even at low temperatures or ambient tempera-
tures (-30-25 °C), whereas classical triazole-forming reactions
require elevated temperatures.
In contrast to (Me3Si)2N-N(SiMe3)-PCl2 (1a), the reac-
tion of the analogous hydrazinoarsane (Me3Si)2N-N(SiMe3)-
AsCl2 with GaCl3 gave no binary arsenic-nitrogen heterocycle.6
In this reaction, both chlorine atoms attached to the arsenic atom
were exchanged by a methyl group from one of the trimethylsilyl
groups at the terminal nitrogen (Scheme 2), and finally, a GaCl3
adduct was formed. The Lewis acid GaCl3 is easily removed by
addition of a stronger base such as 4-(dimethylamino)pyridine
(DMAP).
The different reaction channels observed for (Me3Si)2N-N-
(SiMe3)-PCl2 (1a) and (Me3Si)2N-N(SiMe3)-AsCl2 when
GaCl3 is added prompted us to have a closer look into the
reaction mechanism. For this reason differently substituted hy-
drazinophosphanes of the type (Me3Si)2N-N(SiMe3)-PR1R2
(R1 = Cl with R2 = Me, C6H5, C6F5 and R1 = Me, R2 = C6H5)
have been studied in the reaction with Lewis acids such as ECl3
(E=Al, Ga). Here we report on similar methyl/chlorine exchange
reactions, observed for the first time in substituted hydrazino-
phosphanes, when treated with GaCl3 or AlCl3.
The low-coordination number chemistry of the group 15 ele-
ments (N, P) has been extensively developed in the past thanks to
the use of bulky groups and is now well-established.1-4 It has been
possible to characterize these reactive species due to their kinetic and
thermodynamic stabilization by appropriate substitution.
Only recently reactions of the silylated hydrazinophosphane
(Me3Si)2N-N(SiMe3)-PCl2 (1a) (Scheme 1)5 and the analo-
gous hydrazinoarsane (Me3Si)2N-N(SiMe3)-AsCl26 with GaCl3
as the Lewis acid were investigated. Triggered by the action of
GaCl3 (Scheme 1) (Me3Si)2N-N(SiMe3)-PCl2 (1a) was trans-
formed into a five-membered PN heterocycle (compound 2 in
Scheme 1).7-9 This new reaction has been classified as a formal
GaCl3-assisted [3 þ 2] cycloaddition,10 which only occurs when
Me3Si-Cl elimination releases the hidden 1,3 dipole molecule
and the dipolarophile, respectively. Moreover, at the end of the
reaction sequence the formed heterocycle, the neutral triazadi-
phosphol RN3P2 (R = (Me3Si)2N), is stabilized as GaCl3
mono- or diadduct.7 Interestingly, (Me3Si)2N-N(SiMe3)-
PCl2 (1a) represents an ambivalent species which can react as
dipolarophile and/or as 1,3 dipole. In any case, a Lewis acid
such as ECl3 (E = Ga, Al) or BR3 (R = C6F5) is necessary for (i)
decreasing of the activation barrier for the Me3Si-Cl elimina-
tion5 and (ii) for stabilizing the “naked” azaphosphole by adduct
formation.7-9
Lately, the concept of a GaCl3-assisted [3 þ 2] cycloaddition
has been proven in a series of other reactions, involving even
other heteroelements such as arsenic.6,11 For instance the reac-
tion of the kinetically stabilized iminophosphane Mes*—NdP
—Cl, (Mes* = 2,4,6-tri-tert-butylphenyl), a good dipolarophile,
with (Me3Si)2N-N(SiMe3)-PCl2 (1a), a “disguised” 1,3-dipole,
Received: January 3, 2011
Published: February 22, 2011
r
2011 American Chemical Society
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|

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Scheme 1. Reaction Channels for Substituted (Me3Si)2N-N(SiMe3)-PR1R2 (1a-e) upon Adding ECl3 (E = Al, Ga)
Scheme 2. Methyl/Chlorine Exchange Reaction in the Silylated Hydrazinoarsane
’ RESULTS AND DISCUSSION
observed, also when the electron withdrawing C6F5 group was used
(Scheme 1). In the case of the hydrazino(chloro)methylphosphane
(1e), only adduct formation was found. Obviously, aryl substitution is
needed to stabilize the transition state for a chlorine/methyl exchange
which can be assumed to be a hydrazinophosphenium ion as
displayed in Scheme 3.
Reactions with Si-C bond cleavage catalyzed by the action of
Lewis acids are known.12 For example a methyl migration from
silicon to gallium was found in the reaction of GaCl3 and SiMe4
for which an intermediate with bridging Cl and Me between Si
and Ga was assumed, finally leading to the formation of Me3SiCl
General Remarks. Different hydrazinophosphanes, (Me3Si)2-
N-N(SiMe3)-PR1R2 (1) (Scheme 1) have been studied in the
reaction with Lewis acids of the type ECl3 (E = Al, Ga).
The substitution pattern R1/R2 was changed from Cl/Cl (1a),
Cl/Me (1e), Cl/aryl (aryl = C6H6 (1b), and C6F5 (1c)) to Me/
Ph (1d). While all chlorophosphanes should be capable of forming a
[(Me3Si)2N-N(SiMe3)-PR2]þ ion (besides the formation of
ECl4-) upon addition of the Lewis acid, only for the chlorine/
aryl-substituted species a chlorine/methyl exchange reaction was
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Scheme 3. Possible Reaction Mechanism for the Chlorine/Methyl Exchange Reaction in Aryl-Substituted Chlorohydrazino-
phosphanes (E = Al, Ga; (a) Concerted and (b) Stepwise Reaction)
Scheme 4. 1-Chlorophosphirane Reacting with AlCl3 to Give a Phosphirane-AlCl3 Complex Displaying a Chloro/Methyl
Exchange13
and (MeGaCl2)2. Niecke et al. already described a similar
methyl/chlorine exchange reaction in chlorophosphiranes as
displayed in Scheme 4.13 With these three-membered chloropho-
sphiranes in mind we believe that formation of a cyclic cation,
[(Me3Si)2N-N(SiMe3)-PR]þ (R=aryl), as the reactive inter-
mediate represents the key species for the observed chlorine/methyl
exchange reaction. The cationic intermediate is best stabilized by
aryls but not by the methyl group, which explains the different
reaction channels. A three-membered cation was also discussed for
the Me3SiCl elimination in the reaction sequence which finally led
to the formation of the triazadiphosphole 2 (Scheme 1).14 Pre-
sumably, the reaction occurs either in a concerted manner or
stepwise (Scheme 3, compare reaction pathway a and b).
In the intramolecular Me/Cl exchange reactions as displayed in
Scheme 1, the Lewis acid ECl3 mediates the substitution and forms
an ECl3 adduct at the end of the exchange reaction. Reaction of 3a
and 4 with a Lewis base e.g. 4-(dimethylamino)pyridine (DMAP)
yields the free hydrazinophosphanes, so that ECl3 can be considered
a catalyst.
the GaCl3 diadduct of the six-membered oxadisilathiadiazine
heterocycle O(SiMe2)(NSN)(SiMe2) as hydrolysis product of
the reaction of bis(trimethylsilyl)sulfur diimide and GaCl3.16
However, in these examples of methyl/chlorine exchange reac-
tions, GaCl3 is part of an intermolecular exchange reaction, whereas
in conversions of (Me3Si)2N-N(SiMe3)-P(Cl)R (R = C6H5
(1b), C6F5 (1c)), the Lewis acid GaCl3 works only as a catalyst in
an intramolecular Me/Cl exchange reaction.
Synthesis of Substituted Hydrazinophosphanes. The salt
elimination reaction of chlorophosphanes, R1R2P-Cl, with bis-
[lithium-tris(trimethylsilyl)hydrazide], {Li[N(SiMe3)-N(SiM-
e3)2]}2, in diethyl ether at low temperatures (-60 to -40 °C)
represents a fast and clean reaction (reaction time 1 h, yield >90%
row product) resulting in the formation of LiCl and the
hydrazinophosphanes, (Me3Si)2N-N(SiMe3)-PR1R2 (R1
=
=
Cl with R2 = C6H5 (1b); R1 = Me and R2 = C6H5 (1d); R1,2
Cl (1a); Scheme 5). Furthermore (Me3Si)2N-N(SiMe3)-
P(C6F5)Cl (1c) can easily be prepared when a solution of
(Me3Si)2N-N(SiMe3)-PCl2 (1a) in CH2Cl2 is treated with a
solution of pentafluorophenylsilver, AgC6F5, in CH2Cl2 at
ambient temperature (Scheme 6).
Another similar reaction was reported by Carmalt et al.: The
reaction of GaCl3 with (Me3Si)3N yielded, among other pro-
ducts, dimeric (MeGaCl2)2.15 In that case, the product (MeGa-
Cl2)2 is the result of monochloride substitution and transfer of a
methyl ligand from the silyl group of the amine to the Ga center.
A methyl/chlorine exchange is also assumed in the formation of
It should be noted that the attempted synthesis of N,N0,N0-
tris(trimethylsilyl) hydrazino-chloro(2,4,6-tri-tert- butylphenyl)-
phosphane, (Me3Si)2N—N(SiMe3)—P(Mes*)Cl (Mes* = 2,4,
6-tri-tert-butylphenyl), according to Scheme 5 led to a reaction
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Scheme 5. Synthesis of Hydrazinophosphanes (R1 = Cl with R2 = C6H5 (1b); R1 = Me and R2 = C6H5 (1d); R1 = Cl and R2 = Me
(1e); R1,2 = Cl (1a))
Scheme 6. Synthesis of N,N0,N0-Tris (trimethylsilyl) hydrazine- (pentafluorophenyl) chlorophosphane (Me3Si)2 N-N(SiMe3)-
P (C6F5) Cl (1c)
Scheme 7. Synthesis of Free N0-(Dimethylchlorosilyl)-N,
N0-bis(trimethylsilyl)hydrazino(methyl)(aryl)phosphanes 7
and 8
Lewis acid such as GaCl3 or AlCl3 led to adduct formation
(Scheme 1, compounds 5 and 6) in a straightforward high-yield
reaction, while the chloro/aryl substituted compounds displayed
a chlorine/methyl exchange followed by adduct formation yield-
ing finally N0-(dimethylchlorosilyl)-N,N0-bis(trimethylsilyl)hy-
drazino(methyl)(aryl)phosphanes as ECl3 adducts (Scheme 1,
compounds 3a, 3b, and 4). Addition of a stronger base such
as DMAP afforded the free N0-(dimethylchlorosilyl)-N,N0-
bis(trimethylsilyl)hydrazino(methyl)(aryl)phosphanes (7 aryl
= C6H5, 8 aryl = C6F5) as colorless materials. All species are
air and moisture sensitive. While adducts 3a and 3b were isolated
as colorless crystals, adduct 4 is a colorless viscous oil. Removal of
the GaCl3 in both adducts by means of DMAP led to the solid
materials 7 and 8, respectively (Scheme 7).
Spectroscopic Characterization. All compounds have been
characterized by elemental analysis, vibrational, mass, and NMR
spectroscopy (nuclei: 1H, 13C, 19F, 29Si, 31P).
As previously shown for a series of silylated hydrazinopho-
sphanes (Me3Si)2N-N(SiMe3)-PR1R2 (R1 = R2 = Cl (1a);
R1 = R2 = Ph; R1 = Cl, R2 = Ph (1b))5 there are two possible
isomers: a cis- and a trans-isomer (Scheme 8 top, isomer A and
B).6 The rotation around the P-N bond is sterically hindered
leading to constitution isomers which can be regarded as
diasteromers.5,14 Both isomers can form adducts upon addition
of a Lewis acid ECl3, so that also for the adducts two isomers can
be expected. A more complicated situation is found for adducts 3
and 4 as well as the adduct-free compounds 7 and 8. Due to the
introduction of one ClMe2Si group at only one of the terminal
nitrogen atoms of the hydrazino group, the whole hydrazino
moiety becomes chiral (Scheme 8 bottom). Hence, in addition to
both isomers A1 and B1, two further isomers A2 and B2 must be
considered. Since the phosphorus atom also represents an
asymmetric center two pairs of diastereomers (A1, A2, B1, and
B2) can be observed. Furthermore, for each diastereomer its
mirror image (enantiomer) exists (A10, A20, B10, and B20), lead-
ing to an overall number of eight possible isomers (Scheme 9).
By means of NMR techniques, only the diastereomers can be
distinguished, when measured in achiral solvents.
mixture from which besides the starting material 2,4,6-tri-tert-
butylphenyl-dichlorophosphane, Mes*—PCl2, bis(2,4,6-tri-tert-
butylphenyl)diphosphene, Mes*—PdP—Mes*, and N,N-bis-
(trimethylsilyl) amino-(2,4,6-tri-tert-butylphenyl) phosphazene,
(Me3Si)2N—NdP—Mes*, could be identified. In a second
experiment, we treated (Me3Si)2N—N(SiMe3)—PCl2 (1a)
with LiMes*, but again a mixture of Mes*—PdP—Mes* and
(Me3Si)2N—NdP—Mes* was obtained.
All hydrazinophosphanes, (Me3Si)2N-N(SiMe3)-PR1R2
(R1 = Cl with R2 = C6H5 (1b); R1 = Cl with R2 = C6F5 (1c);
R1 = Me and R2 = C6H5 (1d); R1,2 = Cl (1a)) are thermally stable
up to over 140 °C and are volatile above 60 °C in vacuum. Hence,
they are easily purified by sublimation at 60-120 °C and 10-3
mbar (separation from traces of LiCl) resulting in colorless
ceraceous solids. All species are air and moisture sensitive but
under argon stable over a long period as a solid and in common
organic solvents (e.g., Et2O, CH2Cl2, n-hexane, etc.). The very
good solubility in almost all common organic solvents makes all
compounds good precursors for further synthesis.
The NMR spectra of investigated compounds showed that the
tris(trimethylsilyl)-substituted hydrazinophosphanes 1b-1e and
Synthesis of Hydrazinophosphane Adducts. The treat-
ment of all methyl substituted hydrazinophosphanes with a
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Table 1. 31P{1H} NMR Shifts (25 °C, CD2Cl2, 121.49 MHz)
Scheme 9. Diastereomers (D) and Enantiomers (E) of
Hydrazinophosphanes 7 with Two Chiral Centersa
species
31P NMR shift
(Me2ClSi)(Me3Si)N-N(SiMe3)-P(C6F5)Me (8)
31.3 (A1)
32.7 (A2)
41.0 (A1)
41.8 (A2)
42.9
(Me2ClSi)(Me3Si)N-N(SiMe3)-P(C6H5)Me (7)
(Me3Si)2N-N(SiMe3)-P(Me)Ph (1d)
(Me3Si)2N-N(SiMe3)-PPh2
61.4a
(Me3Si)2N-N(SiMe3)-P(C6F5)Cl (1c)
(Me3Si)2N-N(SiMe3)-P(Cl)Ph (1b)
(Me3Si)2N-N(SiMe3)-P(Cl)Me (1e)
(Me3Si)2N-N(SiMe3)-PCl2 (1a)
105.7
145.2
159.5
166.6a
(Me3Si)2N-N(SiMe3)-P(Me)Ph GaCl3 (5)
33.7 (br)
34.0 (br) (A1)
27.5 (br)
3
(Me2ClSi)(Me3Si)N-N(SiMe3)-P(Ph)Me GaCl3 (3a)
3
(Me2ClSi)(Me3Si)N-N(SiMe3)-P(Ph)Me AlCl3 (3b)
3
(Me2ClSi)(Me3Si)N-N(SiMe3)-P(C6F5)Me GaCl3 (4) 43.6 (br)
3
44.6 (br)
(Me3Si)2N-N(SiMe3)-P(Cl)Me GaCl3 (6)
98.0 (br)
3
a Reference 5.
Scheme 8. Diastereomers of Hydrazinophosphanes
a (top) cis-Isomers A1 and A2 with the according enantiomers A10 and
A20, (bottom) trans-isomers B1 and B2 with the according enantiomers
B10 and B20.
signals are observed in a ratio of 62%: 38%. A closer look at the
region of the SiMe signals shows, that two signals are significantly
shifted compared to the other signals. In fact, one SiMe3 signal of
1
the minor species (δ H = -0.06) and one signal of the two
nonequivalent (diastereotopic) Me groups of the SiMe2Cl
moiety for the major species (δ 1H = -0.11) are high-field shifted.
These findings can only be explained by the anisotropy effect of the
phenyl group which must be arranged nearly to the corresponding
Me groups (on the same side of the N-N-P plane) confirming
here the cis arrangement of the P moiety. Therefore, the major
species (62%) can be defined as the isomer A1, whereas the minor
species proves to be the isomer A2. The same item can be
considered for compound 8 and also for the adducts 3a and 3b.
In the case of the tris(trimethylsilyl)-substituted compounds,
the high-field shift of one Me signal proves again the cis ar-
rangement of the P moiety (isomer A). The fact that for 1e and 6
no high-field shift of any SiMe3 signal was observed is under-
standable due to the absence of the phenyl group and supports
the discussion above.
the adducts 5 and 6 exist in solution as one species which
was confirmed as being the cis-isomers (isomers A). For the
(dimethylchlorosilyl)bis(trimethylsilyl)-substituted compounds
3a, 3b, 4, 7, and 8, signals of two isomers appeared which were
assigned to isomers A1 and A2. The assignment was done on the
basis of the H NMR spectra. For example, in the H NMR
spectrum (as also in spectra of the other nuclei) of 7, having the
dimethylchlorosilyl moiety at the terminal N atom, two sets of
1
1
Also, 31P NMR spectroscopy is a powerful tool to study the
methyl/chlorine exchange reaction, isomers, and the dynamics in
solution. The 31P NMR data are summarized in Table 1.
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Table 2. Crystallographic Details of 1c, 3a, and 3b
Table 3. Crystallographic Details of 5, 6, and 8
1c
3a
3b
5
6
8
chem formula
C
15H27ClF5 C15H32Cl4Ga C15H32AlCl4
chem formula
C
16H35Cl3Ga
C10H30Cl4Ga
N2PSi3
505.12
colorless
monoclinic
P21
C15H27ClF5
N2PSi3
481.08
colorless
monoclinic
P21/c
N2PSi3
481.08
N2PSi3
567.19
colorless
monoclinic
P21/c
N2PSi3
524.45
colorless
monoclinic
P21/n
N2PSi3
546.77
colorless
monoclinic
P21/n
form wght [g mol-1
color
]
form wght [g mol-1
color
]
colorless
monoclinic
P21/c
cryst system
space group
a [Å]
cryst system
space group
a [Å]
15.509(3)
12.823(3)
11.945(2)
99.81(3)
2340.7(8)
4
9.7090(19)
15.819(3)
18.523(5)
110.96(3)
2656.6(10)
4
9.7093(4)
15.8340(5)
17.5820(6)
100.026(2)
2661.73(17)
4
9.8091(3)
15.7487(5)
17.4956(6)
99.759(2)
2663.62(15)
4
8.5157(2)
12.6961(4)
11.0010(3)
99.6790(10)
1172.46(6)
2
16.6656(8)
9.3800(4)
15.2884(8)
99.467(2)
2357.4(2)
4
b [Å]
b [Å]
c [Å]
c [Å]
β [deg]
V [Å3]
β [deg]
V [Å3]
Z
Z
F
calc. [g cm-3
μ [mm-1
MoKR [Å]
T [K]
]
1.365
1.418
1.309
F
calc. [g cm-3
μ [mm-1
MoKR [Å]
T [K]
]
1.363
1.431
1.355
]
0.428
1.639
0.678
]
1.535
1.847
0.425
λ
0.71073
173(2)
24985
0.71073
173(2)
44518
0.71073
173(2)
41783
λ
0.71073
173(2)
47351
0.71073
173(2)
17472
0.71073
173(2)
25693
measured reflections
measured reflections
independent reflections
reflections with I > 2σ(I)
Rint
independent reflections
6751
7710
8468
9630
6068
4628
reflections with I > 2σ(I) 5772
6890
6622
7860
5820
3312
Rint
0.0335
0.0180
1168
0.0292
1096
0.0260
1136
0.0216
520
0.0422
1000
F(000)
1000
F(000)
R1 (R [F2 > 2σ(F2)])
wR2 (F2)
GooF
0.0351
0.1076
1.077
253
0.0330
0.0995
1.059
0.0360
0.1025
1.052
R1 (R [F2 > 2σ(F2)])
wR2 (F2)
0.0299
0.0820
1.069
0.0177
0.0464
1.014
0.1030
0.2632
1.068
GooF
parameters
CCDC no.
244
251
parameters
245
201
471
811885
811886
811887
CCDC no.
811888
811889
811890
As shown in Table 1, the δ 31P values of the NNP species are in
the range expected on the basis of numerous data from the
literature.3,17 Successive replacement of chlorine at phosphorus by
a methyl or phenyl group leads to increased 31P nuclear shielding
(e.g., 1a f1e Δδ31P=-7.1, 1a f1b Δδ31P=-21.4, 1a f 1c Δδ
31P = -60.9).18 As already described for the 1H NMR spectra, it
can be assumed that all considered free hydrazinophosphanes
adopt the cis configuration in solution. Hence, also only a single
31P NMR resonance is observed for all considered species except
from the products of the Me/Cl exchange reaction (7 and 8) for
which two resonances for the diastereomers A1 and A2
(Schemes 8 and 9, Table 1) are observed. According to the 1H
and 31P NMR signal intensities, an A1:A2 ratio of 62:38 is
observed for species 7 and 60:40 for 8, respectively. Substitution
of a C6H5 by a C6F5 moiety decreases the chemical shift from ca.
41/42 (7) to 31/33 ppm (8) (Table 1). Except 1H and 31P NMR,
also the 13C, 19F, and 29Si NMR spectra support the existence of
two diasteromers; however, the substituent effects on the
chemical shifts are less pronounced (e.g., 29Si A1 isomer:
12.5, 13.6, or 14.1, and 19.3 ppm for 7 vs 14.0, 17.2, and 18.5
ppm for 8). According to our NMR study, all adduct-free
hydrazinophosphanes are stable for several days in solution.
However, upon addition of a Lewis acid such as GaCl3, the
spectra change rapidly leading to decomposition and complex
reaction mixtures, respectively. Therefore, it was difficult to
obtain usable spectra of some hydrazinophosphane adducts
(e.g., 4 and 6). For example, according to the 31P NMR
spectra, measured immediately after dissolving hydrazinopho-
sphane GaCl3 adducts 3a, 4, 5, and 6 in CH2Cl2, broad
resonances (adducts) and traces of sharp resonances (adduct-free
hydrazinophosphanes) were observed as well as resonances of
decomposition products.
X-ray Crystallography. The structures of GaCl3 adducts 3a, 5,
and 6, AlCl3 adduct 3b and the free hydrazinophosphanes (Me3-
Si)2N-N(SiMe3)-P(Cl)(C6F5) (1c) and (Me2ClSi)(Me3Si)N-
N(SiMe3)-P(Me)(C6F5) (8) have been determined. Tables 2
and 3 present the X-ray crystallographic data. ORTEP represen-
tations of the molecular structure along with selected structural
data are shown in Figures 1-4.
For compounds of the type (Me3Si)2N-N(SiMe3)-PR1R2,
two diastereomers with respect to the position of the PR1R2 group
can be discussed as displayed in Scheme 8. While addition of a Lewis
acid always leads to the formation of a structure derived from isomer
A due to decreased steric repulsion (Figure 1 and 2), for the free
uncoordinated compounds (e.g., in (Me3Si)2N-N(SiMe3)-PCl2
(1a), (Me3Si)2N-N(SiMe3)-P(Cl)(C6H5) (1b))5,19 often a
configuration according to isomer B, which is energetically
preferred according to quantum chemical calculations, is
found.14 However, in (Me3Si)2N-N(SiMe3)-P(Cl)(C6F5)
(1c) and (Me3Si)2N-N(SiMe3)-P(Me)(C6F5) (8), respec-
tively, a structure of type A is observed. Interestingly, in the
structure of the AlCl3 adduct of (Me2ClSi)(Me3Si)N-N-
(SiMe3)-P(Cl)(C6H5) (3b) (Figure 1 left), the position of
the chlorine atom is disordered, corresponding to a superposi-
tion of both possible diasteromers (A1 and A2) of Scheme 7. The
chlorine atom can either be attached to the Si2 or Si3 atom. Free
refinement of the chlorine occupancy displayed a 0.826-
(2):0.174(2) ratio between both isomers. A similar but even
more complicated disorder is found for (Me2ClSi)(Me3Si)N-
N(SiMe3)-P(Me)(C6F5) (8) (Figures 4 and S1 in the
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Figure 1. ORTEP drawing of GaCl3 or AlCl3 adducts 3a and 3b. Thermal ellipsoids with 30% probability at 173 K (hydrogen atoms omitted). Selected
bond lengths are in angstroms, and angles in degrees. GaCl3 adduct: P-N1 1.679(2), P-C15 1.805(2), P-C1 1.809(2), P-Ga 2.3892(7), Si1-N1
1.805(2), Si3-N2 1.757(2), N1-N2 1.466(2); N1-P-C15 109.21(9), N1-P-C1 112.81(8), C15-P-C1 104.6(1), N1-N2-Si3 118.6(1), N1-
N2-Si2 118.0(1), Si3-N2-Si2 123.23(9), N2-N1-P 116.0(1), N2-N1-Si1 117.6(1), P-N1-Si1 126.27(9). AlCl3 adduct: P-N1 1.686(1), P-
C15 1.810(2), P-C1 1.814(2), P-Al 2.4303(6), Si1-N1 1.799(1), Si2-Cl4B 1.95(1), Si2-C12A 1.87(1), Si3-C12B 1.91(2), Si3-Cl4A 2.077(8),
N1-N2 1.472(2); N1-P-C15 108.44(7), N1-P-C1 111.92(6), C15-P-C1 103.72(8), N2-N1-P 116.60(8), N2-N1-Si1 117.51(8), P-N1-
Si1 125.78(7), N1-N2-Si3 118.55(9), N1-N2-Si2 117.88(9).
Figure 2. ORTEP drawing of GaCl3 adducts 5and 6with thermal ellipsoids with 30% probability at 173 K (hydrogen atoms omitted). Selected bond lengths are
in angstroms, and angles in degrees. 5: Ga-P 2.4201(3), P-N1 1.647(1), P-C1 1.793(2), P-Cl4 2.0470(5), N1-N2 1.463(2), Si1-N1 1.811(1), N2-Si2
1.774(1), Si3-N2 1.771(1); N1-N2-Si2 119.59(9), Si3-N2-Si2 124.07(7), N1-P-C1 110.01(7), N1-P-Cl4 110.83(5), C1-P-Cl4 101.73(6), N2-
N1-P 117.61(8), N2-N1-Si1 119.54(8), P-N1-Si1 122.60(6), N1-N2-Si3 115.88(9). 6: Ga-P 2.3876(3), P-N1 1.674(1), P-C1 1.804(1), P-C2
1.810(1), N1-N2 1.470(1), N1-Si1 1.796(1), N2-Si3 1.774(1), N2-Si2 1.775(1); N1-P-C1 109.75(6), N1-P-C2 113.01(6), C1-P-C2 104.40(7),
N2-N1-P 115.20(8), N2-N1-Si1 118.56(7), P-N1-Si1 126.16(6), N1-N2-Si3 117.58(7), N1-N2-Si2 118.83(7), Si3-N2-Si2 122.93(6).
Supporting Information). Here, the asymmetric unit consists of a
superposition of the two possible diasteromers (A1, A2) due to a
positional disorder of the chlorine position (ratio Cl1a:Cl2a,
0.293(10):0.207(10); ratio Cl1b:Cl2b, 0.319(10):0.181(10)). In
addition the whole molecule lies on a pseudo mirror plane,
leading to a disorder of the whole molecule (1:1 ratio). Hence, all
possible diastereomeres (A1, A2 and A10, A20) of Scheme 9 are
found in the asymmetric unit.
All hydrazinophosphane species adopt a staggered configura-
tion, in which the two planes formed around the two trigonal
planar nitrogen atoms (P—N1—N2—Si3 and N1—N2—Si2
—Si3) are almost perpendicular to each other. This perpendi-
cular configuration is stable. No rotation about the N—N axis is
observed according to NMR studies. The almost trigonal-planar
environment around both nitrogen atoms can be attributed to
hyperconjugative effects caused by delocalization of the nitrogen
lone pair into the σ* Si—C bonds.5,14 The phosphorus atom sits
always in a pyramidal environment with bond angles between
100° and 105°. In contrast to the P—C bond lengths (between
1.79 and 1.85 Å), the experimentally determined P—N bond
lengths of 1.64 - 1.69 Å are considerably shorter than expected for
a typical P—N single bond (cf. Σrcov. = 1.80 (1.76) Å).20,21 Such
short P—N distances (average 1.67 Å) had been previously
found in a series of amino/iminophosphanes (R2N—PdN—
R0)3a and also in cyclodiphosph(V)azenes (P—N: 1.66-1.68
Å).22 The σ bond system along the P—N1—N2 unit is highly
polarized between P1 and N2 and almost ideally covalent
between the adjacent N1—N2 single bond with a bond distance
P
of 1.46-1.47 Å (cf. rcov = 1.4 Å). The P—Cl distances are
rather long with 2.047 Å in 2 and 2.105 Å in (Me3Si)2N—
N(SiMe3)—P(Cl)(C6F5) and compare well with 2.043(3) Å in
PCl3. The slightly increased P—Cl distance in (Me3Si)2N—
N(SiMe3)—P(Cl)(C6F5) can also be explained by hyperconju-
cation as already discussed for (Me3Si)2N—N(SiMe3)—PCl2
and (Me3Si)2N—N(SiMe3)—P(Cl)(C6H5).5,23,24 Due to steric
repulsion, the N—N—P angles in the adduct species between
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The bond between ECl3 (E = Al, Ga) and the phosphorus of
the hydrazinophosphane can be considered as a donor-acceptor
bond.7,25 The Ga P distance of 2.38-2.42 Å is very compar-
3 3 3
able with that in (t-Bu)2(Cl)P GaCl3 (2.40(1) Å)26 and sligh-
3 3 3
tly longer than in the sterically less hindered Me3P GaCl3
3 3 3
(2.353(2) Å).27 The Al P distance amounts to 2.4303(6), in
3 3 3
accord with that found in (Me3Si)3P AlCl3 (2.392(4) Å,28 cf.
3 3 3
P
r
cov = 2.40 Å).20b
’ CONCLUSION
Several hydrazinophosphanes of the type (Me3Si)2N-N-
(SiMe3)-P(Cl)R (R = Me, C6H5, C6F5) and (Me3Si)2N-
N(SiMe3)-P(Me)(C6H5) have been studied in the reaction
with GaCl3 and AlCl3 as Lewis acids. A chlorine/methyl
exchange reaction was observed for (Me3Si)2N-N(SiMe3)-
P(Cl)R (R = C6H5 and C6F5) leading to the formation of (Me2-
ClSi)(Me3Si)N-N(SiMe3)-P(Me)R, after removal of the Le-
wis acid by means of a strong base such as DMAP. In the case of
(Me3Si)2N-N(SiMe3)-P(Cl)(Me) and (Me3Si)2N-N(SiM-
e3)-P(Me)(C6H5), only adduct formation was found. Obviously,
aryl substitution is needed to stabilize the transition state for a
chlorine/methyl exchange which can be assumed to be a hydra-
zinophosphenium ion. The chlorine/methyl exchange can be uti-
lized to generate selectively a (Me3ClSi)(Me3Si)N-N(SiMe3)
group.
Figure 3. ORTEP drawing of (Me3Si)2N-N(SiMe3)-P(Cl)(C6F5)
(1c) with thermal ellipsoids with 30% probability at 173 K (hydrogen
atoms omitted). Selected bond lengths are in angstroms, and angles in
degrees: P-N1 1.671(1), P-C1 1.853(2), P-Cl 2.1050(6), Si1-N1
1.808(1), Si2-N2 1.769(1), Si3-N2 1.776(1), N1-N2 1.461(1);
N1-P-C1 107.1(6), N1-P-Cl 107.80(4), C1-P-Cl 97.07(5),
N2-N1-P 125.46(8), N2-N1-Si1 121.46(8).
’ EXPERIMENTAL DETAILS
General Information. All manipulations were carried out under
oxygen- and moisture-free conditions under argon using standard Schlenk
or drybox techniques.
Dichloromethane was purified according to a literature procedure,29
dried over P4O10, and freshly distilled prior to use. Diethylether and
THF were dried over Na/benzophenone and freshly distilled prior to
use, n-hexane and n-pentane were dried over Na/benzophenone/
tetraglyme and freshly distilled prior to use. AlCl3 (99.999%, Acros),
GaCl3 (99.999%, Sigma-Aldrich), N,N-dimethylaminopyridine DMAP
(99%, Aldrich), and n-BuLi (2.5 M, Acros) were used as received. PCl3
(99%, Acros), methyldichlorophosphane MePCl2 (98%, Merck), and
phenyldichlorophosphane PhPCl2 (97%, Alfa Aesar) were freshly dis-
tilled prior to use. Methylphenylchlorophosphane PhMePCl30 was
prepared according to a literature procedure and freshly destilled prior
to use. Pentafluorophenylsilver AgC6F5,31 Lithium-N,N0,N0-tris(trime-
thlysilyl)hydrazide Li[(Me3Si)2N-N(SiMe3)],32 N,N0,N0-tris(trime-
thylsilyl)hydrazinodichlorophosphane (Me3Si)2N-N(SiMe3)PCl2 (1a),33
and 2,4,6-tri-tert-butylphenyldichlorophosphane Mes*PCl234 have been
reported previously and were prepared according to literature proce-
dures. N,N0,N0-tris(trimethylsilyl)hydrazinochlorophenylphosphane
(Me3Si)2N-N(SiMe3)-PPhCl (1b)5 has been reported previously and
was prepared according to a modified procedure.
Figure 4. ORTEP drawing of the major part of the disordered molecule
8 with thermal ellipsoids with 30% probability at 173 K (hydrogen atoms
omitted). Selected bond lengths are in Å, and angles in degrees: P1-N1
1.689(9), P1-C1 1.897(9), P1-C7 1.97(7), N1-N2 1.49(1), N1-Si1
1.762(9), N2-Si2 1.74(1), N2-Si3 1.78(1), Si2-Cl1 2.026(8); N1-
P1-C1 108.0(5), N1-P1-C7 108(3), C1-P1-C7 105(2), N2-
N1-P1 121.0(7), N2-N1-Si1 120.8(7), P1-N1-Si1 118.1(5), N1-
N2-Si2 119.6(8), N1-N2-Si3 115.5(7), Si2-N2-Si3 122.8(6),
N1-Si1-C9 109.5(8).
NMR. 31P{1H}, 13C{1H}, 29Si INEPT, 19F{1H}, and 1H NMR
spectra were recorded on Bruker spectrometers AVANCE 300 and
AVANCE 500, respectively. The 1H and 13C chemical shifts were
referenced to solvent signals (C6D6: δ 1H = 7.15, δ 13C = 128.0.
CD2Cl2: δ 1H = 5.31, δ 13C = 54.0). The 1H and 13C NMR signals were
assigned by DEPT and two-dimensional correlation spectra (HSQC and
HMBC) using standard pulse sequences (standard Bruker software).
The 19F, 29Si, and 31P chemical shifts are referred to CFCl3, TMS, and
H3PO4 (85%), respectively. CD2Cl2 was dried over P4O10, and C6D6
was dried over Na/benzophenone.
116° and 118° are slightly larger compared with that found
in adduct-free (Me3Si)2N—N(SiMe3)—P(Ph)Cl (110.5(2)°) (iso-
mer B type structure).5 On the contrary, an even larger N—N—P
angle with 125.4° is found for free (Me3Si)2N—N(SiMe3)—P
(Cl)(C6F5), which adopts an isomer A type structure. Here
sterical strain between the C6F5 and the N(SiMe3)2 moieties
causes the larger N—N—P angle.
IR. A Nicolet 380 FT-IR with a Smart Orbit ATR device was used.
Raman. A Bruker VERTEX 70 FT-IR with RAM II FT-Raman
module, equipped with a Nd:YAG laser (1064 nm), was used.
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CHN Analyses. An Analysator Flash EA 1112 from Thermo Quest or
C/H/N/S-Mikroanalysator TruSpec-932 from Leco were used.
Melting Points. These are uncorrected (EZ-Melt, Stanford Research
Systems). A heating rate of 20 °C min-1 (clearing points are reported)
was used.
(3), 392 (1), 338 (1), 230 (3), 205 (2), 184 (2). MS (CIþ, isobutane):
247 [M - PCl(C6F5)]þ, 445 [M - Cl]þ, 481 [M - H]þ.
(Me3Si)2N-N(SiMe3)-P(Me)Ph (1d). To
a solution of
PhPMeCl (0.753 g, 4.75 mmol) in 5 mL Et2O, a solution of
Li[(Me3Si)2N-N(SiMe3)] (1.209 g, 4.75 mmol) in 20 mL Et2O was
added dropwise under stirring over a period of 10 min at -60 °C. The
resulting yellowish solution was stirred for 10 min at -60 °C and was
then warmed to room temperature, resulting in a yellowish suspension
which was stirred for 1 h. The solvent was removed in vacuo, and the
residue was extracted with 10 mL n-hexane and filtered. Removal of
solvent and drying in vacuo resulted in a yellowish ceraceous solid.
Sublimation at 65 °C over a period of 24 h yields 1.42 g (3.83 mmol,
81%) 1d as colorless ceraceous solid. Mp 68 °C. Anal calc % (found) for
C16H35N2PSi3 (370.69): C 51.84 (51.53), H 9.52 (10.07), N 7.56
DSC. A DSC 823e from Mettler-Toledo (heating rate 5 °C/min) was
used.
MS. A Finnigan MAT 95-XP from Thermo Electron was used.
(SiMe3)2N-N(SiMe3)-P(Cl)Ph (1b). To a solution of PhPCl2
(0.895 g, 5.00 mmol) in 10 mL Et2O at -40 °C, a solution of
Li[(Me3Si)2N-N(SiMe3)] (1.273 g, 5.00 mmol) in 25 mL Et2O was
added dropwise under stirring over a period of 10 min. The mixture was
stirred for 2 h at -40 °C and was then warmed to room temperature and
stirred for 10 min. The solvent was removed in vacuo, and the colorless
residue was extracted with 20 mL n-hexane and filtered, resulting in a
yellowish solution. Removal of solvent in vacuo resulted in a colorless
solid. Sublimation at 65 °C for 12 h in vacuo yields 1.435 g (3.67 mmol
73%) of 1b as a colorless crystalline solid. All analytical data are identical
1
(7.71). H NMR (25 °C, CD2Cl2, 300.13 MHz): δ = 0.00 (s, 9H,
Si(CH3)3), 0.22 (d, 9H, J(31P-1H) = 0.8 Hz, Si(CH3)3), 0.29 (s, 9H,
2
Si(CH3)3), 1.60 (d, 3H, J(31P-1H) = 7.6 Hz, CH3), 7.34-7.42 (m,
3H, m-Ph, p-Ph), 7.70 (m, 2H, o-Ph). 13C{1H} NMR (25 °C, CD2Cl2,
75.5 MHz): δ = 3.4 (d, J(31P-13C) = 1.4 Hz, Si(CH3)3), 3.7 (d,
J(31P-13C) = 5.5 Hz, Si(CH3)3), 3.8 (d, J(31P-13C) = 1.0 Hz,
Si(CH3)3), 14.9 (d, 1J(31P-13C) = 19.2 Hz, CH3), 128.3 (d,
3J(31P-13C) = 6.6 Hz, m-Ph), 129.6 (s, p-Ph), 133.8 (d, 2J(31P-13C) =
1
to the literature. Additional data. H NMR (25 °C, CD2Cl2, 300.13
MHz): δ = 0.01 (s, 9H, Si(CH3)3), 0.23 (s, 9H, Si(CH3)3), 0.32 (d, 9H,
J(31P-1H) = 0.8 Hz, Si(CH3)3), 7.44 (m, 3H, m-Ph, p-Ph), 7.95 (m, 2H,
o-Ph). 13C{1H} NMR (25 °C, CD2Cl2, 75.5 MHz): δ = 3.1 (d,
J(31P-13C) = 2.3 Hz, Si(CH3)3), 3.2 (br, J(31P-13C) = 0.9 Hz,
Si(CH3)3), 3.5 (d, J(31P-13C = 3.7 Hz, Si(CH3)3), 128.5 (d,
3J(31P-13C) = 6.9 Hz, m-Ph), 131.0 (m, p-Ph), 133.0 (d, 2J(31P-13C)
1
22.4 Hz, o-Ph), 141.5 (d, J(31P-13C) = 20.4 Hz, i-Ph). 29Si NMR
(25 °C, CD2Cl2, 59.6 MHz): δ = 8.9, 8.9, 12.4. 31P{1H} NMR (25 °C,
CD2Cl2, 121.5 MHz): δ = 42.9. IR (ATR, 32 scans): 3073 (w), 3055
(w), 2952 (m), 2900 (m), 1486 (w), 1473 (w), 1434 (m), 1415 (m),
1323 (w), 1306 (w), 1246 (s), 1179 (w), 1157 (w), 1099 (m), 1070 (w),
1024 (m), 897 (s), 828 (s), 770 (s), 742 (s), 698 (s), 670 (s), 639 (m),
618 (m), 603 (m), 582 (m), 531 (w). Raman (400 mW, 1000 scans,
25 °C, cm-1): 3058 (3), 2957 (5), 2903 (10), 1587 (2), 1572 (1), 1412
(1), 1263 (1), 1247 (1), 1180 (1), 1157 (1), 1099 (1), 1028 (2), 1002
(4), 917 (1), 901 (1), 844 (1), 742 (1), 674 (2), 640 (3), 619 (1), 510
(1), 493 (1), 433 (1), 403 (2), 319 (1), 296 (1), 236 (2), 204 (1). MS
(CIþ, isobutane): 73 [SiMe3]þ, 174 [Me3Si - NN - SiMe3], 210 [M -
(PhMeP)]þ, 355 [M - Me]þ, 371 [M þ H]þ.
1
= 27.0 Hz, o-Ph), 138.6 (d, J(31P-13C) = 38.4 Hz, i-Ph). 29Si NMR
(25 °C, CD2Cl2, 59.6 MHz): δ = 10.2, 11.0, 19.0. 31P{1H} NMR (25 °C,
CD2Cl2, 121.5 MHz): δ = 145.2. IR (ATR, 32 scans) 3076 (w), 3047
(w), 3020 (w), 2952 (m), 2901 (m), 1477 (m), 1462 (w), 1432 (m),
1402 (m), 1357 (w), 1330 (w), 1309 (m), 1266 (m), 1248 (s), 1182
(m), 1157 (m), 1086 (m), 1072 (m), 1020 (m), 1003 (w), 992 (w), 937
(s), 914 (s), 863 (w), 831 (m), 814 (m), 768 (m), 745 (s), 698 (m), 687
(m), 662 (m), 645 (w), 621 (m), 590 (s).
(Me3Si)2N-N(SiMe3)-P(C6F5)Cl (1c). To a solution of (Me3
Si)2N-N(SiMe3)-PCl2 (0.689 g, 2.00 mmol) in 5 mL CH2Cl2, a
solution of AgC6F5 (0.577 g, 2.10 mmol) in 20 mL CH2Cl2 was added
dropwise under stirring over a period of 20 min at room temperature.
The yellow suspension was stirred 20 min at room temperature.
Removal of solvent in vacuo resulted in a yellowish solid which was
extracted with 10 mL n-hexane. The yellow suspension was filtered, and
the solvent was removed in vacuo, resulting in a yellow oil. Sublimation
at 95 °C for 20 h in vacuo yields 0.285 g (0.59 mmol, 22%) of 1c as a
colorless ceraceous solid. Mp 91 °C. Anal calc % (found) for C15H27
ClF5N2PSi3 (481.06): C 37.45 (37.16), H 5.66, (5.40), N 5.82 (5.72).
1H NMR (25 °C, CD2Cl2, 300.13 MHz): δ = 0.08 (s, 9H, Si(CH3)3),
0.288 (d, 9H, J(31P-1H) = 0.5 Hz, Si(CH3)3), 0.295 (d, 9H, J(31P-1H)
= 1.0 Hz, Si(CH3)3). 13C{1H} NMR (25 °C, CD2Cl2, 75.5 MHz): δ =
3.0 (d, J(31P-13C) = 6.5 Hz, Si(CH3)3), 3.1 (d, J(31P-13C) = 0.8 Hz,
Si(CH3)3), 3.3 (m, Si(CH3)3), 115.0 (m, i-C6F5), 138.0 (m, 1J-
(Me3Si)2N-N(SiMe3)-P(Cl)Me (1e). To a solution of MePCl2-
(0.368 g, 3.15 mmol) in 10 mL Et2O at -60 °C, a solution of
(Me3Si)2N-N(SiMe3)Li (0.764 g, 3.00 mmol) in 10 mL Et2O was
added dropwise under stirring over a period of 10 min. The resulting
suspension was stirred for 10 min at -60 °C and was then warmed to
room temperature. After stirring for 2 h at this temperature, the solvent
was removed in vacuo and 10 mL n-hexane was added. Filtration and
removal of solvent in vacuo yielded 0.585 g (1.77 mmol, 60%) of 1e as a
colorless solid. Mp 137 °C (dec). Anal calc % (found) for C10H30ClN2PSi3
(329.04): C 36.50 (34.37), H 9.19 (8.90), N 8.51 (8.74). 1H NMR (25 °C,
CD2Cl2, 300.13 MHz): δ=0.23(s,9H, Si(CH3)3), 0.25(s, 9H, Si(CH3)3),
2
0.34 (s, 9H, Si(CH3)3), 1.86 (d, 3H, J(31P-1H) = 14.0 Hz, CH3).
13C{1H} NMR (25 °C, CD2Cl2, 75.5 MHz): δ = 2.82 (d, 3J(31P-13C) =
4
4.8 Hz, Si(CH3)3), 2.93 (s, Si(CH3)3), 3.04 (d, J(31P-13C) = 2.8 Hz,
1
1
(19F-13C) = 255 Hz), 147.7 (m, J(19F-13C) = 255 Hz), (o-C6F5,
Si(CH3)3), 22.8 (d, J(31P-13C) = 33.0 Hz, CH3). 29Si NMR (25 °C,
1
m-C6F5), 144.0 (m, J(19F-13C) = 152 Hz, p-C6F5). 19F{1H} NMR
CD2Cl2, 59.6 MHz): δ = 10.2, 10.2, 17.4. 31P{1H} NMR (25 °C, CD2Cl2,
121.5 MHz): δ = 159.5. IR (ATR, 32 scans): 2954 (m), 2900 (m), 1410
(m), 1248 (s), 1046 (w), 1026 (w), 956 (m), 916 (s), 901 (s), 872 (s), 829
(s), 815 (s), 768 (s), 754 (s), 675 (s), 664 (w), 641 (m), 619(m), 607 (m),
586 (m). Raman (500 mW, 800 scans, 25 °C, cm-1): 2957 (5), 2903 (10),
1412 (2), 1263 (1), 1249 (1), 1047 (1), 875 (1), 840 (1), 771 (1), 752 (1),
696 (2), 682 (2), 663 (2), 641 (5), 518 (1), 505 (1), 481 (1), 436 (2), 415
(2), 377 (2), 356 (1), 327 (1), 290 (1), 234 (2), 189 (2), 140 (1), 109 (1).
MS (FABþ, NBA): 293 [M - Cl]þ, 313 [M - Me]þ, 327 [M - H]þ.
(25 °C, CD2Cl2, 282.4 MHz): δ = -126.1 (m, 2F), -149.4 (tt, 1F,
3J(19F-19F) = 20.5 Hz, 4J(19F-19F) = 5.0 Hz), -161.3 (m, 2F). 29Si
NMR (25 °C, CD2Cl2, 59.6 MHz): δ = 10.5, 12.1, 21.1. 31P{1H} NMR
(25 °C, CD2Cl2, 121.5 MHz): δ = 105.7 (t, 3J(31P-19F) = 64.0 Hz). IR
(ATR, 32 scans): 2960 (m), 2904 (m), 1636 (m), 1515 (s), 1469 (s),
1407 (m), 1379 (m), 1284 (m), 1265 (w), 1249 (s), 1142 (m), 1084 (s),
1049 (w), 1026 (w), 1003 (w), 978 (s), 902 (m), 882 (m), 831 (w), 818
(w), 780 (m), 768 (w), 754 (m), 727 (m), 678 (m), 659 (m), 646 (w),
629 (m), 608 (m), 584 (m), 571 (m). Raman (200 mW, 1049 scans,
25 °C, cm-1): 2963 (5), 2909 (10), 2794 (1), 2755 (1), 1638 (2), 1520
(1), 1413 (2), 1379 (1), 1312 (1), 1286 (1), 1269 (1), 1249 (1), 1139
(1), 1089 (1), 1048 (1), 976 (1), 885 (1), 826 (1), 784 (1), 746 (1), 683
(2), 649 (5), 631 (1), 586 (2), 522 (1), 506 (2), 468 (2), 444 (2), 419
(Me2ClSi)(Me3Si)N-N(SiMe3)-P(Ph)Me GaCl3 (3a). To a
3
solution of (Me3Si)2N-N(SiMe3)-P(Ph)Cl (0.782 g, 2.00 mmol) in
10 mL CH2Cl2 at -70 °C, a solution of GaCl3 (0.370 g, 2.10 mmol) in
5 mL CH2Cl2 was added dropwise under stirring over a period of 10 min.
The red solution was warmed to room temperature and stirred for 12 h.
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The resulting colorless solution was concentrated to incipient crystal-
lization in vacuo and stored at -25 °C for a period of 12 h, resulting in
the deposition of colorless crystals. After removal of supernatant by
syringe, the crystals were washed with 1 mL n-hexane and dried in vacuo
which yields 0.675 g (1.19 mmol, 60%) of 3a as a colorless crystalline
solid. Mp 177 °C. Anal calc % (found) for C15H32Cl4GaN2PSi3
(567.19): C 31.76 (30.66), H 5.69 (5.70), N 4.94 (4.53). NMR:
(ratio A1:A2 = 62:38). (A1) 1H NMR (25 °C, CD2Cl2, 300.13 MHz):
δ = -0.06 (s, 3H, SiCl(CH3)2), 0.43 (s, 9H, Si(CH3)3), 0.51 (s, 3H,
m-Ph), 7.59-7.63 (m, 1H, p-Ph). 13C{1H} NMR (25 °C, CD2Cl2, 75.5
MHz): δ = 3.1 (s, Si(CH3)3), 3.9 (s, Si(CH3)3), 5.7 (s, SiCl(CH3)2), 6.5
(s, SiCl(CH3)2), 9.6 (d, 1J(31P-13C) = 37.5 Hz, CH3), 129.4 (d,
3J(31P-13C) = 10.5 Hz, m-Ph), 130.9 (d, 1J(31P-13C) = 13.5 Hz) or
1
131.1 (d, J(31P-13C) = 12.8 Hz) (i-Ph), 133.3 (s, p-Ph), 134.0 (d,
2J(31P-13C) = 12.0 Hz, o-Ph). 31P{1H} NMR (25 °C, CD2Cl2, 121.5
MHz): δ = 27.5 (br). IR (ATR, 32 scans): 3059 (w), 2957 (m), 2920 (w),
2903 (w), 1589 (m), 1486 (w), 1439 (m), 1410 (m), 1316 (w), 1300 (m),
1257 (s), 1162 (w), 1120 (m), 1102 (w), 1042 (m), 1004 (w), 974 (m),
939 (w), 898(m), 878 (m), 830(s), 807 (s), 744(s), 689(s), 650 (m), 637
(m), 606 (w), 591 (m). Raman (700 mW, 1500 scans, 25 °C, cm-1): 3176
(1), 3149 (1), 3070 (3), 3019 (2), 2995 (3), 2963 (4), 2908 (10), 1590 (3),
1576 (1), 1413 (2), 1271 (1), 1191 (1), 1164 (1), 1104 (1), 1029 (2), 1001
(3), 948 (1), 916 (1), 880 (1), 849 (1), 795 (1), 757 (1), 733 (1), 693 (3),
656 (1), 638 (3), 618 (1), 517 (1), 507 (1), 478 (1), 455 (1), 421 (2), 400
(1), 379 (1), 346 (3), 308 (1), 250 (2), 211 (1), 181 (1), 158 (1), 129 (1),
110 (1). MS (FABþ, NBA): 210 [M - AlCl3 - N(SiMe3)SiMe3Cl]þ, 355
[M - AlCl3 - Cl]þ, 391 [M - AlCl3 þ H]þ.
2
SiCl(CH3)2), 0.53 (s, 9H, Si(CH3)3), 2.35 (d, 3H, J(31P-1H) = 7.6
Hz, CH3), 7.52-7.69 (m, 3H, m-Ph, p-Ph), 7.95 (m, 2H, o-Ph).
13C{1H} NMR (25 °C, CD2Cl2, 75.5 MHz): δ = 3.4 (s, Si(CH3)3),
3.4 (s, SiCl(CH3)2), 3.5 (s, Si(CH3)3), 6.1 (s, SiCl(CH3)2), 8.3 (d,
1J(31P-13C) = 45.0 Hz, CH3), 129.5 (d, 3J(31P-13C) = 11.0 Hz, m-Ph),
1
131.0 (d, J(31P-13C) = 13.5 Hz, i-Ph), 133.9 (s, p-Ph), 134.3 (d,
2J(31P-13C) = 11.9 Hz, o-Ph). 29Si NMR (25 °C, CD2Cl2, 59.6 MHz):
δ = 17.2, 22.5, 24.6 (or 24.2). 31P{1H} NMR (25 °C, CD2Cl2, 121.5
MHz): δ = 34.0 (br). (A2) 1H NMR (25 °C, CD2Cl2, 300.13 MHz): δ =
0.06 (s, 9H, Si(CH3)3), 0.53 (s, 9H, Si(CH3)3), 0.76 (s, 3H, SiCl-
(CH3)2), 0.79 (s, 3H, SiCl(CH3)2), 2.30 (d, 3H, 2J(31P-1H) = 7.6 Hz,
CH3), 7.52-7.69 (m, 3H, m-Ph, p-Ph), 7.83 (m, 2H, o-Ph). 13C{1H}
NMR (25 °C, CD2Cl2, 75.5 MHz): δ = 3.2 (s, Si(CH3)3), 3.7
(s, Si(CH3)3), 5.7 (s, SiCl(CH3)2), 6.4 (s, SiCl(CH3)2), 9.6 (d,
1J(31P-13C) = 43.0 Hz, CH3), 129.6 (d, 3J(31P-13C) = 11.0 Hz, m-Ph),
131.0 (d, 1J(31P-13C) = 13.5 Hz, i-Ph), 134.0 (d, 2J(31P-13C) = 11.5
Hz, o-Ph), 134.0 (s, p-Ph). 29Si NMR (25 °C, CD2Cl2, 59.6 MHz): δ =
16.2, 24.2 (or 24.6), 25.1. 31P{1H} NMR (25 °C, CD2Cl2, 121.5 MHz):
δ = 34.0 (br). IR (ATR, 32 scans): 3086 (w), 3061 (w), 2958 (m), 2920
(w), 2902 (w), 1588 (m), 1575 (w), 1486 (m), 1462 (w), 1439 (m),
1411 (m), 1335 (w), 1317 (m), 1298 (m), 1284 (w), 1256 (s), 1163
(m), 1120 (m), 1104 (m), 1019 (m), 1002 (w), 974 (m), 915 (w), 894
(m), 879 (m), 827 (m), 808 (m), 795 (w), 745 (s), 689 (s), 653 (s), 638
(w), 604 (m), 592 (m). Raman (200 mW, 400 scans, 25 °C, cm-1):
3068 (3), 2995 (4), 29863 (4), 2909 (10), 2845 (1), 2814 (1), 2789 (1),
1589 (3), 1414 (1), 1321 (1), 1190 (1), 1165 (1), 1105 (1), 1029
(2), 1001 (3), 922 (1), 843 (1), 736 (1), 692 (2), 655 (2), 638 (1), 617
(1), 595 (1), 556 (1), 530 (1), 502 (1), 477 (1), 448 (1), 416 (1), 383
(1), 343 (5), 238 (1), 196 (1), 177 (1), 156 (1), 136 (2). MS (CIþ,
isobutane): 355 [M - Cl - GaCl3]þ, 391 [M - GaCl3 þ H]þ.
(Me2ClSi)(Me3Si)N-N(SiMe3)-P(C6F5)Me GaCl3 (4). To a
3
solution of (Me3Si)2N-N(SiMe3)-P(C6F5)Cl (0.285 g, 0.592 mmol)
in 4 mL CH2Cl2 a solution of GaCl3 (0.110 g, 0.622 mmol) in 3 mL
CH2Cl2 was added dropwise under stirring over a period of 10 min at
-70 °C. The red solution was stirred for 10 min at this temperature and
was then warmed to room temperature. Stirring for 12 h at this
temperature resulted in a yellowish solution. Removal of solvent in
vacuo yielded 0.320 g (0.87 mmol, 82%) of 4 as a colorless viscous oil.
Mp 3 °C (144 °C dec). Anal calc % (found) for C15H27Cl4F5GaN2PSi3
(657.15): C 27.42 (26.87), H 4.14 (4.22), N 4.26 (4.04). NMR: (ratio
A1:A2 = 60:40). 31P{1H} NMR (25 °C, CH2Cl2/C6D6, 121.5 MHz): δ =
43.6 (br), 44.6 (br). IR (ATR, 32 scans): 2959 (m), 2920 (m), 1646 (m),
1591 (w), 1520 (s), 1490 (s), 1398 (m), 1307 (m), 1259 (s), 1153 (w),
1107 (s), 1089 (w), 1028 (m), 971 (m), 950 (w), 898 (m), 880 (w), 834
(s), 807 (m), 754 (m), 725 (w), 684 (m), 647 (m), 631 (w), 584 (m).
Raman (400 mW, 1000 scans, 25 °C, cm-1): 2994 (3), 2965 (4), 2909
(10), 2814 (1), 1646 (2), 1591 (1), 1523 (1), 1483 (1), 1416 (2), 1307
(1), 1272 (1), 1232 (1), 1085 (1), 1029 (1), 979 (1), 946 (1), 902 (1),
875 (1), 844 (1), 797 (1), 752 (1), 734 (1), 685 (2), 639 (3), 588 (2),
512 (2), 446 (2), 421 (2), 394 (2), 358 (2), 345 (3), 288 (1), 246 (1),
204 (1), 180 (1), 151 (1), 135 (1), 115 (1).
(Me3Si)2N-N(SiMe3)-P(Me)Ph GaCl3 (5). To a solution of
(Me2ClSi)(Me3Si)N-N(SiMe3)-P(Ph)Me AlCl3 (3b). To a
3
3
(Me3Si)2N-N(SiMe3)-P(Me)Ph (0.371 g, 1.00 mmol) in 5 mL
CH2Cl2 at -60 °C a solution of GaCl3 (0.185 g, 1.05 mmol) in 5 mL
CH2Cl2 was added dropwise under stirring over a period of ten minutes.
The colorless solution was warmed to room temperature and stirred for
three hours. The solution was then concentrated to incipient crystal-
lization in vacuo and stored at room temperature for one hour, resulting
in the deposition of colorless crystals. Removal of supernatant and
drying in vacuo yield 0.39 g (0.71 mmol, 71%) of 5 as a colorless
crystalline solid. Mp 190 °C. Anal calc % (found) for C16H35Cl3GaN2P-
Si3 (546.77): C 35.15 (34.47), H 6.45, (6.54), N 5.12 (5.23). 1H NMR
(25 °C, CD2Cl2, 300.13 MHz): δ = -0.04 (s, 9H, Si(CH3)3), 0.34 (s,
9H, Si(CH3)3), 0.49 (s, 9H, Si(CH3)3), 2.21 (d, 3H, 2J(31P-1H) = 7.0
Hz, CH3), 7.51-7.65 (m, 3H, m-Ph, p-Ph), 7.79 (m, 2H, o-Ph).
13C{1H} NMR (25 °C, CD2Cl2, 75.5 MHz): δ = 3.23 (s, Si(CH3)3),
3.63 (s, Si(CH3)32), 3.72 (s, Si(CH3)3), 8.8 (d, 2J(31P-13C) = 43.0 Hz,
CH3), 129.4 (d, J(31P-13C) = 11.8 Hz, m-Ph), 133.5 (br d, p-Ph),
133.8 (d, 2J(31P-13C) = 11.8 Hz, o-Ph), i-Ph not displayed. 29Si NMR
(25 °C, CD2Cl2, 59.6 MHz): δ = 13.0, 13.8, 22.6. 31P{1H} NMR (25 °C,
CD2Cl2, 121.5 MHz): δ = 33.7 (br). IR (ATR, 32 scans): 2956 (m),
2900 (m), 1588 (m), 1574 (w), 1485 (m), 1439 (m), 1410 (m), 1317
(w), 1298 (w), 1282 (w), 1253 (s), 1164 (m), 1120 (m), 1103 (m), 1014
(w), 1004 (w), 994 (w), 976 (m), 920 (s), 878 (s), 826 (s), 771 (s), 749
(s), 691 (s), 667 (s), 643 (m), 623 (m), 600 (m), 585 (m). Raman (200
mW, 1049 scans, 25 °C, cm-1): 3177 (1), 3149 (1), 3071 (4), 3061 (3),
suspension of AlCl3 (0.051 g, 3.785 mmol) in 5 mL CH2Cl2 at
-30 °C a solution of (Me2ClSi)(Me3Si)N-N(SiMe3)-P(Ph)Me
(0.160 g, 0.361 mmol) in 2 mL CH2Cl2 was added under stirring. After
30 min stirring at -30 °C, the colorless suspension was warmed to room
temperature and stirred for 1 h. The resulting colorless solution was then
concentrated to incipient crystallization in vacuo and stored at room
temperature for 1 h, resulting in the deposition of colorless crystals.
Removal of supernatant by syringe and drying in vacuo yielded 0.136 g
(0.259 mmol, 72%) of 3b as colorless crystals. Mp 104 °C (dec). Anal
calc % (found) for C15H32AlCl4N2PSi3 (524.45): C 34.35 (34.34), H
6.15 (6.36), N 5.34 (5.53). NMR: (ratio A1:A2 = 65:35). (A1) 1H NMR
(25 °C, CD2Cl2, 300.13 MHz): δ = -0.08 (s, 3H, SiCl(CH3)2), 0.43 (s,
9H, Si(CH3)3), 0.47 (s, 3H, SiCl(CH3)2), 0.53 (s, 9H, Si(CH3)3), 2.25
(d, 3H, 2J(31P-1H) = 5.8 Hz, CH3), 7.93 (m, 2H, o-Ph), 7.52-7.58 (m,
2H, m-Ph), 7.59-7.63 (m, 1H, p-Ph). 13C{1H} NMR (25 °C, CD2Cl2,
75.5 MHz): δ = 3.4 (s, Si(CH3)3), 3.4 (s, SiCl(CH3)2), 3.7 (s,
Si(CH3)3), 6.1 (s, SiCl(CH3)2), 8.3 (d, 1J(31P-13C) = 40.3 Hz,
CH3), 129.3 (d, 3J(31P-13C) = 10.5 Hz, m-Ph), 130.9 (d, 1J(31P-13C)
= 13.5 Hz) or 131.1 (d, 1J(31P-13C) = 12.8 Hz) (i-Ph), 133.3 (s, p-Ph),
134.2 (d, 2J(31P-13C) = 12.5 Hz, o-Ph). 31P{1H} NMR (25 °C,
CD2Cl2, 121.5 MHz): δ = 27.5 (br). (A2) 1H NMR (25 °C, CD2Cl2,
300.13 MHz): δ = 0.02 (s, 9H, Si(CH3)3), 0.54 (s, 9H, Si(CH3)3), 0.73
(s, 3H, SiCl(CH3)2), 0.78 (s, 3H, SiCl(CH3)2), 2.19 (d, 3H,
2J(31P-1H) = 5.5 Hz, CH3), 7.82 (m, 2H, o-Ph), 7.52-7.58 (m, 2H,
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ARTICLE
3023 (2), 2995 (3), 2961 (5), 2928 (5), 2907 (10), 1589 (3), 1576 (1),
1411 (1), 1272 (1), 1252 (1), 1190 (1), 1164 (1), 1145 (1), 1
104 (1), 1029 (2), 1001 (2), 924 (1), 880 (1), 854 (1), 751 (1), 736
(1), 692 (1), 667 (1), 643 (3), 617 (1), 506 (1), 448 (1), 420 (1),
400 (1), 380 (1), 356 (3), 342 (1), 270 (1), 232 (1), 197 (1), 152 (1),
137 (1), 111 (1), 99 (1), 83 (2). MS (FABþ, NBA): 210 [M - GaCl3 -
N(SiMe3)(SiMe2Cl)]þ, 247 [N(SiMe3)N(SiMe3)2]þ, 355 [M -
Me]þ, 371 [M - GaCl3 þ H]þ.
(25 °C, CD2Cl2, 59.6 MHz): δ = 11.7, 14.1 (or 13.6), 19.6. 31P{1H}
NMR (25 °C, CD2Cl2, 121.5 MHz): δ = 41.8. IR (ATR, 32 scans):
3072 (w), 3055 (w), 2957 (m), 2903 (m), 2366 (w), 2355 (w), 2336
(w), 1434 (m), 1414 (m), 1308 (m), 1247 (s), 1180 (w), 1158 (m),
1099 (m), 1070 (w), 1022 (m), 1002 (w), 985 (w), 923 (s), 896 (s),
854 (m), 829 (m), 808 (m), 790 (m), 744 (s), 698 (m), 679 (m), 652
(s), 633 (m), 618 (m), 607 (s), 589 (m), 556 (w). Raman (200 mW,
400 scans, 25 °C, cm-1): 3057 (3), 2962 (5), 2906 (10), 1586 (2),
1572 (1), 1503 (1), 1411 (1), 1317 (1), 1290 (1), 1250 (1), 1180 (1),
1098 (1), 1027 (1), 1002 (2), 936 (1), 899 (1), 873 (1), 792 (1), 749
(1), 703 (1), 679 (1), 651 (1), 633 (1), 496 (1), 468 (1), 433 (1), 396
(1), 318 (1), 137 (1). MS (CIþ, isobutane): 355 [M - Cl]þ, 391
[M þ H]þ.
(Me3Si)2N-N(SiMe3)-P(Cl)Me GaCl3 (6). To a solution of
3
(Me3Si)2N-N(SiMe3)-P(Cl)Me (0.443 g, 1.35 mmol) in 5 mL
CH2Cl2 at -60 °C a solution of GaCl3 (0.250 g, 1.418 mmol) in
5 mL CH2Cl2 was added dropwise under stirring over a period of 10 min.
The colorless solution was stirred for 10 min at -60 °C and was then
warmed to room temperature. The yellowish solution was then concen-
trated to incipient crystallization in vacuo and stored at room temperature
for one hour, resulting in the deposition of colorless crystals. Removal of
supernatant by syringe and drying in vacuo yielded 0.49 g (0.97 mmol, 72%)
of 6 as a colorless crystalline solid. Mp 92 °C (dec). Anal calc % (found) for
C10H30Cl4GaN2PSi3 (505.12): C 23.78 (23.60), H 5.99, (5.99), N 5.55
(5.81). 1H NMR (25 °C, CD2Cl2, 300.13 MHz): δ = 0.28 (s, 9H,
Si(CH3)3), 0.37 (s, 9H, Si(CH3)3), 0.54 (s, 9H, Si(CH3)3), 2.38 (br s,
3H, CH3). 31P{1H} NMR (25 °C, CD2Cl2, 121.5 MHz): δ = 98.0 (br). IR
(ATR, 32 scans): 2957 (m), 2904 (w), 1444 (w), 1406 (m), 1297 (w),
1284 (m), 1256 (s), 1162 (w), 1108 (w), 1015 (m), 1000 (w), 923 (m),
890 (s), 826 (s), 769 (w), 758 (m), 679 (w), 667 (m), 654 (w), 645 (w),
621 (m), 606 (m). Raman (200 mW, 1049 scans, 25 °C, cm-1): 2964 (4),
2906 (10), 1413 (1), 1273 (1), 1254 (1), 1035 (1), 930 (1), 849 (1), 734
(1), 685 (1), 644 (4), 609 (1), 497 (1), 434 (1), 393 (2), 343 (5), 252 (1),
200 (1), 131 (1), 116 (1), 104 (1), 91 (1).
(Me2ClSi)(Me3Si)N-N(SiMe3)-P(C6F5)Me (8). To a solution
of (Me2ClSi)(Me3Si)N-N(SiMe3)-P(C6F5)Me GaCl3 (4) (0.600 g,
3
0.913 mmol) in 10 mL CH2Cl2, a solution of N,N-dimethylaminopyr-
idine (0.117 g, 0.959 mmol) in 5 mL CH2Cl2 was added dropwise under
stirring over a period of 10 min at 0 °C. The resulting yellowish solution
was stirred for 10 min at 0 °C and was then warmed to room
temperature. After stirring for 1 h at this temperature, the solvent was
removed in vacuo and a yellowish solid was obtained. Extraction with 8
mL n-hexane, filtration, and removal of solvent in vacuo resulted in a
yellowish oil which slowly solidifies upon standing. Sublimation at 60 °C
for 3 h yields 74 mg (0.15 mmol, 16%) of 8 as a colorless crystalline solid.
Mp 52 °C. Anal calc % (found) for C15H27ClF5N2PSi3 (481.06): C
37.45 (37.43), H 5.66 (4.75), N 5.82 (5.63). NMR: (ratio A1:A2 =
60:40). (A1) 1H NMR (25 °C, CD2Cl2, 300.13 MHz): δ = 0.04 (s, 3H,
SiCl(CH3)2), 0.32 (s, 9H, Si(CH3)3), 0.33 (d, 9H, J(31P-1H) = 1.1 Hz,
Si(CH3)3), 0.44 (s, 3H, SiCl(CH3)2), 1.75 (dt, 3H, 2J(31P-1H) = 9.4
Hz, J(19F-1H) = 1.6 Hz, CH3). 13C{1H} NMR (25 °C, CD2Cl2, 75.5
MHz): δ = 3.00 (s, Si(CH3)3), 3.21 (s, Si(CH3)3), 4.49 (d, 4J(31P-13C) =
1.8 Hz), SiCl(CH3)2), 5.83 (s, SiCl(CH3)2), 12.2-14.5 (m, CH3).
19F{1H} NMR (25 °C, CD2Cl2, 282.4 MHz): δ = -161.6 (m, 2F),
-151.1 (tt, 1F, 3J(19F-19F) = 20.4 Hz, 4J(19F-19F) = 4.0 Hz), -127.4
(m, 2F). 29Si NMR (25 °C, CD2Cl2, 59.6 MHz): δ = 14.0, 17.2, 18.5.
31P{1H} NMR (25 °C, CD2Cl2, 121.5 MHz): δ = 31.3 (t, 3J(31P-19F) =
44.0 Hz). (A2) 1H NMR (25 °C, CD2Cl2, 300.13 MHz): δ = 0.03 (s,
9H, Si(CH3)3), 0.31 (d, 9H, J(31P-1H) = 1.1 Hz, Si(CH3)3), 0.57 (s,
3H, SiCl(CH3)2), 0.62 (s, 3H, SiCl(CH3)2), 1.79 (dt, 3H, 2J(31P-1H) =
9.7 Hz, J(19F-1H) = 1.6 Hz, CH3). 13C{1H} NMR (25 °C, CD2Cl2,
75.5 MHz): δ = 2.9-3.1 (m, Si(CH3)3), 5.53 (s, SiCl(CH3)2), 5.88 (s,
SiCl(CH3)2), 12.2-14.5 (m, CH3). 19F{1H} NMR (25 °C, CD2Cl2,
282.4 MHz): δ = -162.0 (m, 2F), -151.4 (tt, 1F, 3J(19F-19F) = 20.4
Hz, 4J(19F-19F) = 4.0 Hz), -127.4 (m, 2F). 29Si NMR (25 °C, CD2Cl2,
59.6 MHz): δ = 12.2, 17.2, 20.4. 31P{1H} NMR (25 °C, CD2Cl2, 121.5
MHz): δ = 32.7 (t, 3J(31P-19F) = 44.0 Hz). IR (ATR, 32 scans): 2958
(m), 2903 (m), 2141 (m), 1940 (w), 1640 (m), 1514 (s), 1463 (s), 1417
(m), 1376 (m), 1284 (m), 1251 (s), 1137 (w), 1083 (s), 1020 (m), 974
(s), 918 (m), 901 (s), 861 (m), 831 (m), 808 (w), 792 (w), 754 (m), 729
(m), 710 (w), 681 (m), 655 (m), 633 (m), 605 (m), 588 (m), 534 (m).
Raman (400 mW, 1000 scans, 25 °C, cm-1): 3479 (1), 2969 (5), 2910
(10), 1640 (2), 1514 (1), 1498 (1), 1416 (2), 1376 (1), 1316 (1), 1283
(1), 1250 (1), 1180 (1), 1137 (1), 1082 (1), 1022 (1), 979 (1), 907 (1),
868 (1), 823 (1), 794 (1), 754 (1), 685 (2), 656 (1), 636 (3), 586 (2),
559 (1), 503 (2), 446 (2), 410 (3), 397 (2), 379 (1), 339 (1), 308 (1),
231 (1), 208 (1), 138 (1), 111 (1). MS (CIþ, isobutane): 445 [M -
Cl]þ, 481 [M þ H]þ.
(Me2ClSi)(Me3Si)N-N(SiMe3)-P(C6H5)Me (7). To a solution
of (Me2ClSi)(Me3Si)N-N(SiMe3)-P(Ph)Me GaCl3 (3a) (1.718 g,
3
3.04 mmol) in 10 mL CH2Cl2, a solution of N,N-dimethylaminopyr-
idine (0.389 g, 3.187 mmol) in 5 mL CH2Cl2 was added dropwise under
stirring over a period of 10 min at 0 °C. The colorless suspension was
stirred for 10 min at 0 °C and was then warmed to room temperature.
After stirring for ten minutes, the solvent was removed in vacuo,
resulting in a colorless residue. After addition of 10 mL n-hexane and
stirring for 10 min in the supersonic bath, the suspension was filtered,
resulting in a colorless solution. Removal of solvent and drying in vacuo
resulted in a colorless solid. Sublimation at 65 °C for 2 h in vacuo yielded
0.787 g (2.02 mmol, 66%) of 7 as a colorless ceraceous solid. Mp 164 °C.
Anal calc % (found) for C15H32ClN2PSi3 (391.11): C 46.06 (45.17), H
1
8.25 (7.99), N 7.16 (7.28). NMR: (ratio A1:A2 = 62:38). (A1) H
NMR (25 °C, CD2Cl2, 300.13 MHz): δ = -0.11 (s, 3H, SiCl(CH3)2),
0.26 (d, 9H, J(31P-1H) = 0.8 Hz, Si(CH3)3), 0.35 (s, 9H, Si(CH3)3),
0.36 (s, 3H, SiCl(CH3)2), 1.55 (d, 3H, 2J(31P-1H) = 7.5 Hz, CH3),
7.35-7.40 (m, 3H, m-Ph, p-Ph), 7.67 (m, 2H, o-Ph). 13C{1H} NMR
(25 °C, CD2Cl2, 75.5 MHz): δ = 3.3 (d, J(31P-13C) = 1.8 Hz,
Si(CH3)3), 3.4 (d, J(31P-13C) = 2.2 Hz, Si(CH3)3), 4.4 (d,
4J(31P-13C) = 1.8 Hz, SiCl(CH3)2), 5.5 (s, SiCl(CH3)2), 14.6 (d,
1J(31P-13C) = 17.9 Hz, CH3), 128.5 (d, 3J(31P-13C) = 7.5 Hz, m-Ph),
2
130.2 (s, p-Ph), 134.2 (d, J(31P-13C) = 23.8 Hz, o-Ph), 140.2 (d,
1J(31P-13C) = 17.4 Hz, i-Ph). 29Si NMR (25 °C, CD2Cl2, 59.6 MHz):
δ = 12.5, 13.6 (or 14.1), 19.3. 31P{1H} NMR (25 °C, CD2Cl2, 121.5
MHz): δ = 41.0. (A2) 1H NMR (25 °C, CD2Cl2, 300.13 MHz): δ =
-0.06 (s, 9H, Si(CH3)3), 0.23 (d, 9H, J(31P-1H) = 0.8 Hz, Si(CH3)3),
0.61 (s, 3H, SiCl(CH3)2), 0.63 (s, 3H, SiCl(CH3)2), 1.62 (d, 3H,
2J(31P-1H) = 7.5 Hz, CH3), 7.35-7.40 (m, 3H, m-Ph, p-Ph), 7.74 (m,
2H, o-Ph). 13C{1H} NMR (25 °C, CD2Cl2, 75.5 MHz): δ = 2.9 (d,
J(31P-13C) = 1.5 Hz, Si(CH3)3), 3.3 (d, J(31P-13C) = 1.0 Hz,
Si(CH3)3), 5.2 (s, SiCl(CH3)2), 6.4 (d, 4J(31P-13C) = 1.0 Hz, SiCl-
(CH3)2), 14.9 (d, 1J(31P-13C) = 17.9 Hz, CH3), 128.4 (d,
3J(31P-13C) = 7.5 Hz, m-Ph), 130.0 (s, p-Ph), 134.3 (d, 2J(31P-13C)
= 23.4 Hz, o-Ph), 140.1 (d, 1J(31P-13C) = 17.0 Hz, i-Ph). 29Si NMR
’ ASSOCIATED CONTENT
S
Supporting Information. Experimental information,
b
structure elucidation, synthesis of compounds, references, and
a crystallographic information file. This material is available free
of charge via the Internet at http://pubs.acs.org.
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dx.doi.org/10.1021/ic200005q |Inorg. Chem. 2011, 50, 2691–2702

Inorganic Chemistry
ARTICLE
’ AUTHOR INFORMATION
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453–461.
Corresponding Author
*E-mail: axel.schulz@uni-rostock.de.
(14) Schulz, A.; Villinger, A. Struc. Chem. 2009, 20, 59–62.
(15) Carmalt, C. J.; Mileham, J. D.; White, A. J. P.; Williams, D. J.;
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’ ACKNOWLEDGMENT
We are indepted to R. Kuzora and Dr. C. Hubrich (Univ.
Rostock). Generous support by the University of Rostock is
gratefully acknowledged. We would like to thank the Deutsche
Forschungsgemeinschaft (SCHU 1170/4-1) for financial
support.
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