Reactivity of carbonyl-functionalized phosphaalkenes RC(O)P=C(NMe2)2 (R = tBu, ph) towards electrophiles

Article abstract of DOI:10.1002/(sici)1099-0682(199912)1999:12<2369::aid-ejic2369>3.0.co;2-s

The reaction of the carbonyl-functionalized phosphaalkenes RC(O)P=C(NMe₂)₂ [R = tBu (2a), Ph (2b)] with protic acids and alkylating reagents occurred at the two-coordinate phosphorus atom to give the phosphanyl-substituted carbocations 3a,b and 4a,b. In contrast, treatment with Me₃SiOSO₂CF₃ resulted in attack at the oxygen atom by the silyl group, and the formation of [RC(OSiMe₃)= PC(NMe₂)₂]SO₃CF₃ (5a,b). Similarly, the Lewis acids B(C₆F₅)₃, Al(tBu)₂Cl and AlMe₃ were ligated to the oxygen atom of the carbonyl group. Two equivalents of GaMe₃ were added to the oxygen and phosphorus atom of the phosphaalkene to yield the thermolabile complexes [RC(OGaMe₃)=P(GaMe₃)C(NMe₂)₂] (10a,b). In contrast, one molecule of InMe₃ was bound to the phosphorus center of the phosphorus compound. Reaction of the phosphaalkenes with [Ni(CO)₄], [Fe₂(CO)₉] or [{(Z)-cyclooctene}Cr(CO)₅] also took place at the pnictogen atom, resulting in complexes of the type [RC(O)P{M(CO)(n)}C(NMe₂)₂] (R = tBu, Ph; M = Ni, n = 3; Fe, n = 4; Cr, n = 5). The chemical transformations reported here underline the versatile chemistry of phosphaalkenes and emphasize a relationship between carbonyl- functionalized phosphaalkenes and the well-investigated class of phosphorus ylides. X-ray structures of compounds 6b, 7b*, 10a, 11a and 12a are reported.

Full text of DOI:10.1002/(sici)1099-0682(199912)1999:12<2369::aid-ejic2369>3.0.co;2-s

FULL PAPER
Reactivity of Carbonyl-Functionalized Phosphaalkenes RC(O)P؍C(NMe2)2
(R ؍ tBu, Ph) towards Electrophiles
Lothar Weber,*[a] Stefan Uthmann,[a] Hans-Georg Stammler,[a] Beate Neumann,[a]
Wolfgang W. Schoeller,[a] Roland Boese,[b] and Dieter Bläser[b]
Dedicated to Professor Dirk Walther on the occasion of his 60th birthday
Keywords: Alkylation / Carbonyl complexes / Lewis acids / Phosphaalkenes / Protonation
The reaction of the carbonyl-functionalized phosphaalkenes
RC(O)P=C(NMe2)2 [R = tBu (2a), Ph (2b)] with protic acids
and alkylating reagents occurred at the two-coordinate
[RC(OGaMe3)=P(GaMe3)C(NMe2)2] (10a,b). In contrast, one
molecule of InMe3 was bound to the phosphorus center of
the phosphorus compound. Reaction of the phosphaalkenes
phosphorus atom to give the phosphanyl-substituted with [Ni(CO)4], [Fe2(CO)9] or [{(Z)-cyclooctene}Cr(CO)5] also
carbocations 3a,b and 4a,b. In contrast, treatment with took place at the pnictogen atom, resulting in complexes of
Me3SiOSO2CF3 resulted in attack at the oxygen atom by the the type [RC(O)P{M(CO)n}C(NMe2)2] (R = tBu, Ph; M = Ni,
silyl group, and the formation of [RC(OSiMe3)=
n = 3; Fe, n = 4; Cr, n = 5). The chemical transformations
PC(NMe2)2]SO3CF3 (5a,b). Similarly, the Lewis acids
reported here underline the versatile chemistry of
B(C6F5)3, Al(tBu)2Cl and AlMe3 were ligated to the oxygen phosphaalkenes and emphasize
a relationship between
atom of the carbonyl group. Two equivalents of GaMe3 were
added to the oxygen and phosphorus atom of the
phosphaalkene to yield the thermolabile complexes
carbonyl-functionalized phosphaalkenes and the well-
investigated class of phosphorus ylides. X-ray structures of
compounds 6b, 7b*, 10a, 11a and 12a are reported.
Introduction
The chemistry of low-coordination phosphorus com-
pounds is a rapidly expanding field that highlights the re-
markable ability of phosphorus to mimic the chemistry of
carbon.[1] In the vast majority of phosphaalkenes R1Pϭ
CR2R3 and phosphaalkynes RCϵP, the multiple bonds are
polarized in the sense Pδϩ···CδϪ, as anticipitated by the dif-
ferent electronegativities of phosphorus and carbon. It was
pointed out by Regitz et al. that in phosphatriafulvenes A
(Scheme 1) the PϭC bond has an inverse electron density;[2]
this was substantiated by quantum chemical calculations in
comparison to the parent compound HPϭCH2. The latter
molecule has a σ ϩ π Mulliken charge distribution of
ϩ0.154 electrons at the phosphorus and Ϫ0.564 electrons
at the carbon atom, whereas the PC π-bond is essentially
nonpolar (ϩ0.021 eϪ at P; 0.021 eϪ at C). In the cyclopro-
pylidene phosphane A a σ ϩ π Mulliken charge distribution
of Ϫ0.037 eϪ at the phosphorus and of Ϫ0.177 eϪ at the
carbon atom of the exocyclic double bond were calculated.
Here the PC π-bond is clearly polarized towards the phos-
phorus atom as the negative end of the dipole with an ex- ation into the Hückel aromatic cyclopropenium unit (for-
cess of 0.369 eϪ at the P atom and a deficiency of 0.084 eϪ mula B in Scheme 1).
at the C-atom. The positive charge is stabilized by incorpor-
Grobe et al. discovered that the introduction of one di-
alkylamino group at the carbon atom of the double bond
in molecules such as F3CPϭC(F)NR2 also resulted in an
inverse electron distribution of the PϭC π-bond.[3] In order
to uncover the role of an amino group on the electron dis-
tribution in a phosphaalkene we performed quantum
chemical calculations at a density functional level [B3LYP/
6Ϫ31 g(d)].[4aϪ4e]
[a]
Fakultät für Chemie der Universität Bielefeld,
Universitätsstrasse 25, D-33615 Bielefeld, Germany
Fax: (internat.) ϩ49(0)521/106Ϫ6146
E-mail: lothar.weber@uni-bielefeld.de
[b]
Institut für Anorganische Chemie der Universität Ϫ
Gesamthochschule Essen,
Universitätsstraße 5Ϫ7, D-45117 Essen, Germany
Eur. J. Inorg. Chem. 1999, 2369Ϫ2381
WILEY-VCH Verlag GmbH, D-69451 Weinheim, 1999
1434Ϫ1948/99/1212Ϫ2369 $ 17.50ϩ.50/0
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L. Weber et al.
FULL PAPER
In the W(CO)5 complex of the inversely polarized phos-
phatriafulvene MesPϭCaCb(tBu)ϪCctBu(CaϪCc), however,
˚
the PC double bond [1.679(5) A ] is retained, and the phos-
phorus atom is pyramidalized to a lesser extent (sum of
angles 352.9°).[2b]
From carbanion and ylide chemistry[8] it is well docu-
mented that the negative charge on a carbon center is effec-
tively stabilized by adjacent carbonyl groups via π-delocal-
ization. In keeping with this, stabilization of the negative
charge on the P-atom in phosphatriafulvenes[2b] and amino-
functionalized phosphaalkenes has been achieved by acyl,
dithiocarboxy, and thiocarbamoyl groups.[9] A significant
charge transfer from phosphorus to the acyl-substituents
was documented in the IR spectra, where the ν(CO) bands
exhibited marked shifts to lower wavenumbers. Thus, in the
IR spectrum of RC(O)PϭC(NMe2)2, ν(CO) bands at 1563
cmϪ1 (R ϭ tBu) and 1546 cmϪ1 (R ϭ Ph) are found;[9] the
IR spectrum of the “normally polarized” phosphaalkene
tBuC(O)PϭC(OSiMe3)(tBu) shows a ν(CO) band at 1664
cmϪ1 [10]
which is well within the range of ν˜ ϭ 1630Ϫ1690
,
cmϪ1 usually encountered in acyl phosphanes.[11] Although
a number of P-acyl phosphaalkenes with an inverse electron
density have been prepared, information on the chemistry
of these molecules is scarce. Thus, only dimerization and
isomerization processes of several phosphatriafulvenes, as
well as the formation of the complex [tBuC(O)P-
{W(CO)5}ϭCaϪCb(tBu)ϭCctBu](CaϪCc) have been inves-
tigated.[2b]
We decided to study in more detail the chemical reactivity
of tBuC(O)PϭC(NMe2)2 (2a) and PhC(O)PϭC(NMe2)2
(2b), which are readily available from Me3SiPϭC(NMe2)2
(1) and carboxylic acid chlorides, especially with respect to
the related carbonyl-stabilized phosphorus ylides
Scheme 2. Charge distribution in HPϭCH2 and amino-substi-
tuted phosphaalkenes
As has been found previously[2] the calculations predict RC(O)CHϭPPh3. Here we report on the reactions of 2a
that the parent phosphaalkene should have a nonpolar π- and 2b with protic acids, alkylating and silylating reagents,
bond (NBO charges and populations),[4d] although one am- organometallic compounds of group 13 elements, and tran-
ino group or, to a greater extent, two amino groups at the sition metal carbonyl complexes.
carbon atom[5] induce an inverse electron-density distri-
bution at the π-bond, i.e. the charge at the phosphorus is
increased relative to the parent methylenephosphane.
Alternatively, an amino group at the phosphorus does the
opposite, it enhances π-electron density at the carbon atom.
Results and Discussion
Phosphaalkenes with an inverse electron density exhibit pe-
Reaction of 2a,b With Protic Acids, ROSO2CF3
cularities in their coordination behavior towards 18 VE
(R ؍ Me, SiMe3) and B(C6F5)3
transition metal fragments. In η1-complexes of normally
polarized phosphaalkenes (PδϩϭCδϪ) such as [(MesPϭ
CPh2)Cr(CO)5] a trigonal planar phosphorus atom is linked
The reaction of the P-acyl phosphaalkenes 2a and 2b
to the methylene carbon atom by a PϭC double bond of with equimolar amounts of ethereal HBF4 in diethyl ether
[6a]
In the complex [(η5-C5Me5)(CO)2- at Ϫ50°C led to the formation of the phosphanyl carben-
˚
1.679(4) A.
FeP[Cr(CO)5]C(NMe2)2], however, where the inversely pol- ium salts [RC(O)P(H)C(NMe2)2][BF4] 3a (R ϭ tBu) and 3b
arized phosphaalkene [(η5-C5Me5)(CO)2FePϭC(NMe2)2] is (Ph) (Scheme 3). Salt 3a was obtained as a colorless solid
η1-ligated to the [Cr(CO)5] group, a trigonal-pyramidal and 3b as a yellow viscous oil. Both compounds are highly
phosphorus atom (sum of angles 346.1°) forms a single soluble in CH2Cl2 and CHCl3. In chloroform, however,
[7]
˚
bond of 1.793(5) A to the planar carbon atom. For com- slow decomposition occurred at ambient temperature.
parison, in the free phosphaalkene a PϭC double bond of Methylation of 2a and 2b was effected by methyl trifluoro-
[7c]
˚
1.709(5) A was measured.
Obviously the zwitterionic methanesulfonate (methyl triflate) in diethyl ether at
structures of inversely polarized phosphaalkenes are stabil- Ϫ50°C. Compounds 4a and 4b were isolated as orange, air-
ized by ligation to metal centers.
and moisture-sensitive powders, which are highly soluble in
2370
Eur. J. Inorg. Chem. 1999, 2369Ϫ2381

Reactivity of Carbonyl-Functionalized Phosphaalkenes
FULL PAPER
60.6 Hz in 4a and from 78.5 and 78.7 Hz in 2b to 39.4 and
37.7 Hz in 4b. Again the ν(CO) bands in the IR spectra of
the salts 4a (ν˜ ϭ 1644, 1588 cmϪ1) and 4b (ν˜ ϭ 1647, 1587
cmϪ1) are observed at higher wavenumbers than in the neu-
tral phosphaalkenes 2a and 2b.
These observations compare well with carbonyl-stabilized
ylides RC(O)CHϭPPh3, their corresponding phosphonium
salts [RC(O)CH2PPh3]ϩXϪ, and their transition metal com-
plexes, where the position of the ν(CO) band in the IR spec-
tra serves as a sensitive probe for their electronic situation.
Thus, the IR spectra of the ylides MeC(O)CHϭPPh3 and
PhC(O)CHϭPPh3 display strong carbonyl bands at ν˜ ϭ
1540 and 1500 cmϪ1, which upon protonation to the corre-
sponding phosphonium ions were shifted to 1710 and 1665
cmϪ1, respectively.[12]
The silylation of 2a and 2b with equimolar amounts of
trimethylsilyl triflate in diethyl ether gave the extremely air-
and moisture-sensitive salts 5a and 5b, which were isolated
as pale yellow oils (Scheme 3). Here, in contrast to the pro-
tonation and methylation of 2a and 2b, a deshielding of the
31P NMR resonances to δ ϭ 109.2 (5a) and δ ϭ 101.0 (5b)
was observed.
In the region typical for the stretching vibrations of acylic
carbonyl groups in the IR spectra of 5a and 5b no intense
bands are present. This situation is best explained by an
attack of the hard acid “Me3Si” at the hard oxygen center
Scheme 3. Reaction of 2a,b with HBF4, CH3OSO2CF3 and Me3-
SiOSO2CF3
halogenated hydrocarbons. In the 31P NMR spectrum, the of the carbonyl group with the formation of a SiϪO and a
protonated products 3a and 3b display doublets at δ ϭ PϭC bond. Thus, the products can be regarded as salts with
Ϫ53.7 (1JPH ϭ 245 Hz) and δ ϭ Ϫ46.6 (1JPH ϭ 257.7 Hz) unsymmetrical phosphaallyl cations or, alternatively, as
which are significantly shifted to high field with respect to phosphaalkenyl-functionalized carbocations. Symmetrical
the corresponding signals in 2a (δ ϭ 26.4) and 2b (δ ϭ phosphaallyl cations such as [(Me2N)2CPC(NMe2)2]ϩ[13] or
31.3). The size of the 31P{1H} coupling constants furthers [{tBuCcϪ(tBu)CbϪCa}2P]ϩ(CaϪCc)[2b] were described sev-
the idea that the protonation occurred at the phosphorus eral years ago. In the low-field region of the 13C{1H} NMR
center of the phosphaalkene. The resonances of the 13C nu- spectra of 5a and 5b, doublets at δ ϭ 180.8 (1JPC
ϭ
clei of the PCN2 and the PCϭO groups of the starting ma- 75.5 Hz) and δ ϭ 181.0 (1JPC ϭ 72.4 Hz) were attributed to
1
1
terials 2a [δ ϭ 201.4 (d, JPC ϭ 80.5 Hz), 231.4 (d, JPC
ϭ
the diaminocarbenium center, whereas the 13C nuclei of the
1
90.8 Hz)] and 2b [δ ϭ 199.3 (d, JPC ϭ 78.5 Hz), 215.6 (d, PCOSi units were observed as doublets at δ ϭ 226.1
1JPC ϭ 78.7 Hz)] are also high-field shifted upon pro- (1JPC ϭ 77.3 Hz) (5a) and δ ϭ 211.8 (1JPC ϭ 61.4 Hz)
tonation, and are observed in 3a as broad singlets at δ ϭ (5b),respectively.
178.1 and δ ϭ 220.0 and in 3b at δ ϭ 177.9 and 204.8,
Thus, the main spectroscopic evidence for an electrophilic
1
respectively. In the H NMR spectrum a doublet at δ ϭ attack at the P- or O-atom of P-acyl phosphaalkenes with
6.02 (1JPH ϭ 245 Hz) (3a) and at δ ϭ 6.23 (1JPH
257.7 Hz) (3b) accounts for the PH unit.
ϭ
inverse electron density is taken from the direction in which
the 31P NMR resonance of the product is shifted. With this
The IR spectrum of 2a shows a very strong ν(CO) ab- in mind, we decided to react 2a and 2b with the hard Lewis
sorption at ν˜ ϭ 1563 cmϪ1, which is hypsochromically acids B(C6F5)3, tBu2AlCl, and (AlMe3)2.
shifted in the carbenium ion of 3a [ν(CO) ϭ 1680, 1597
Treatment of 2a or 2b with tris(pentafluorophenyl)borane
cmϪ1]. Similar observations were made with 2b and 3b. The in toluene solution at room temperature gave the adducts
methylation of 2a and 2b to yield the phosphanyl carben- 6a or 6b as yellow solids (Scheme 4).
ium salts 4a and 4b, gave rise to high-field shifts of only
The air- and moisture-sensitive compounds are only
30Ϫ33 ppm in the 31P NMR spectra. In the 13C{1H} NMR slightly soluble in dichloromethane or chloroform, but dis-
spectra the 13C nuclei of the methyl groups of 4a and 4b solve well in acetonitrile. In ethereal and hydrocarbon sol-
were observed as doublets at δ ϭ 6.0 (1JPC ϭ 13.3 Hz) and vents 6a and 6b are insoluble. Low-field shifted singlets in
δ ϭ 5.0 (1JPC ϭ 11.7 Hz), respectively, which is consistent the 31P{1H} NMR spectra at δ ϭ 68.3 (6a) (∆δ ϭ 41.9) and
with an alkylation at the P-atom of the P-acyl phosphaal- 72.6 (6b) (∆δ ϭ 41.5), and the absence of ν(CϭO) bands in
kenes. Upon methylation, the 13C nuclei of the CN2 and the the IR spectra of the adducts agree with the ligation of the
PCO units of precursors 2a and 2b are shielded by phosphaalkenes to the electron-deficient boron center via
1
21.8Ϫ23.8 and 5.6Ϫ8.7 ppm, and the JPC coupling con- the oxygen atom. Doublets in the 13C{1H} NMR spectra at
stants decreased from 80.5 and 90.8 Hz in 2a to 44.0 and δ ϭ 188.4 (1JPC ϭ 89.0 Hz) and 190.9 (1JPC ϭ 80.6 Hz) are
Eur. J. Inorg. Chem. 1999, 2369Ϫ2381
2371

L. Weber et al.
FULL PAPER
readily assigned to the three-coordinate 13C nuclei of the to atom C(41) by a single bond of 1.482(3) A. The former
˚
˚
˚
diaminocarbenium units in 6a and 6b. Low-field resonances PC(N) bond in 2b [1.800(1) A] is lengthened to 1.838(3) A
at δ ϭ 228.8 (d, 1JPC ϭ 81.4 Hz, 6a) and δ ϭ 223.4 (1JPC ϭ in 6b. The trigonal-planar carbon atom C(2) (sum of angles
359.4°) shows multiple bonding to the planarly configured
nitrogen atoms [N(1)ϪC(2) ϭ 1.333(4); N(2)ϪC(2) ϭ
˚
1.327(4) A]. The bond angle C(1)ϪP(1)ϪC(2) [102.3(1)°] is
close to the value found in HPϭC(NMe2)2 [103(1)°].[5] This
is presumably because of the steric hinderance between the
cis-oriented diaminocarbenium group and the phenyl ring
which means that the valence angle P(1)ϪC(1)ϪC(41)
[127.5(2)°] is markedly more obtuse than P(1)ϪC(1)ϪO(1)
[121.4(2)°]. The very bulky B(C6F5)3 moiety is directed
towards the P-atom of the PC multiple bond, giving rise to
torsion angles B(1)ϪO(1)ϪC(1)ϪP(1) and B(1)ϪO(1)Ϫ
C(1)ϪC(41) of 2.5° and Ϫ179.4°, respectively. The torsion
Scheme 4. Reaction of 2a,b with B(C6F5)3
71.1 Hz, 6b) are due to the 13C nuclei of the PCOB units.
X-ray Structural Analysis of 6b
angle C(2)ϪP(1)ϪC(1)ϪO(1) was determined to be
Ϫ175.1°. Thus, the atoms B(1), O(1), C(1), C(41), P(1) and
C(2) are located in one plane, and the molecule may be
described as a zwitterionic phosphaalkene, where the posi-
tive charge is formally centered at the diaminocarbenium
substituent, and a negative charge at the boron atom.
To confirm the spectroscopic evidence for the ligation of
the phosphaalkene to the borane, an X-ray structural analy-
sis of 6b was performed (Figure 1, Table 1). Single crystals
of 6b were grown from toluene at Ϫ30°C. The analysis con-
firms the presence of a tetracoordinate boron atom, which
is attached to the carbonyl group via a single bond of
˚
1.506(3) A. Delocalization of the negative charge into the
Reaction of 2a and 2b With tBu2AlCl
˚
CϭO bond is obvious from an elongation from 1.240(2) A
(as measured in 2b)[14] to 1.315(3) A and by the bond length
˚
Di-tert-butylaluminium chloride smoothly reacted with
an equimolar amount of 2a or 2b in toluene at Ϫ30°C to
afford the adducts 7a or 7b (Scheme 5). They were obtained
as extremely moisture-sensitive orange solids. Attempts to
grow crystals of 7a and 7b from C6D6 solution at 6°C
within a period of 3 weeks led to the formation of crystal-
line RC[OAl(tBu)Cl2]ϭPC(NMe2)2 [R ϭ tBu (7a*), Ph
(7b*)] instead.
˚
P(1)ϪC(1) of 1.735(2) A, which is similar to the PϭC bond
[5]
˚
length in HPϭC(NMe2)2 [1.740(1) A].
planar carbon atom C(1) (sum of angles 359.9°) is linked
The trigonal-
Figure 1. Molecular structure of 6b in the crystal (fluorine atoms
Scheme 5. Reaction of 2a,b with tBu2AlCl
˚
at the borane unit are omitted for clarity); selected bond lengths [A]
and angles [°]: P(1)ϪC(1) 1.735(2), P(1)ϪC(2) 1.838(3), O(1)ϪC(1)
1.315(3), O(1)ϪB(1) 1.506(3), B(1)ϪC(11,21,31) av. 1.649(4),
In the IR spectra of the adducts 7a and 7b, no unambi-
1
C(1)ϪC(41) 1.482(3), N(1)ϪC(2) 1.333(4), N(2)ϪC(2) 1.327(4), gious identification of ν(CO) bands was possible. The H
N(1)ϪC(3) 1.459(4), N(1)ϪC(4) 1.481(4), N(2)ϪC(5) 1.465(5),
NMR spectrum of 7a was characterized by a singlet for the
N(2)ϪC(6) 1.474(5); C(1)ϪP(1)ϪC(2) 102.3(1), C(1)ϪO(1)ϪB(1)
nine protons of the tert-butyl group at the PϭC function,
and by another singlet accounting for the 18 protons of the
tert-butyl groups at the aluminium atom. A singlet at δ ϭ
2.63 was assigned to the protons of the dimethylamino
groups.
130.2(2), O(1)ϪC(1)ϪC(41) 111.0(2), P(1)ϪC(1)ϪO(1) 121.4(2),
P(1)ϪC(1)ϪC(41) 127.5(2), P(1)ϪC(2)ϪN(1) 115.6(2), P(1)Ϫ
C(2)ϪN(2) 123.6(2), N(1)ϪC(2)ϪN(2) 120.2(3), C(2)ϪN(1)ϪC(3)
122.7(2), C(2)ϪN(1)ϪC(4) 122.8(3), C(3)ϪN(1)ϪC(4) 113.8(3),
C(2)ϪN(2)ϪC(5) 122.7(3), C(2)ϪN(2)ϪC(6) 122.3(4), C(5)Ϫ
N(2)ϪC(6) 114.0(4), O(1)ϪB(1)ϪC(11) 111.1(2), O(1)ϪB(1)Ϫ
C(21) 115.4(2), O(1)ϪB(1)ϪC(31) 107.0(3), C(11)ϪB(1)ϪC(21)
In the low-field region of the 13C{1H} NMR spectra of
7a and 7b, doublets at δ ϭ 184.4 (1JPC ϭ 76.5 Hz) and
115.4(2),
112.1(2).
C(11)ϪB(1)ϪC(31)
107.0(2),
C(21)ϪB(1)ϪC(31)
2372
Eur. J. Inorg. Chem. 1999, 2369Ϫ2381

Reactivity of Carbonyl-Functionalized Phosphaalkenes
Table 1. Important bond lengths of compounds 2b, 6b, 7b*, 10a, 11a, and 12a in A
FULL PAPER
˚
Comp.
M
d(CϭO)
d[PC(O)]
d[PC(N)]
d(MϪP)
d(MϪO)
2b
Ϫ
B
Al
Ga
In
Cr
1.240(2)
1.315(3)
1.309(2)
1.249(3)
1.238(10)
1.225(2)
1.805(1)
1.735(2)
1.728(2)
1.784(3)
1.851(9)
1.848(2)
1.800(1)
1.838(3)
1.844(2)
1.831(3)
1.823(8)
1.833(2)
Ϫ
Ϫ
Ϫ
Ϫ
6b
1.506(3)
1.776(1)
2.109(2)
Ϫ
7b*
10a
11a
12a
2.635(2)
2.774(4)
2.516(1)
Ϫ
185.3 (1JPC ϭ 71.8 Hz) were found for the carbon atoms crystals for an X-ray diffraction analysis. A yellow crystal
of the diaminocarbenium unit. Again, adduct formation is of 7b* [PhC{OAl(tBu)Cl2}ϭPC(NMe2)2] was studied by X-
accompanied by a high-field shift [∆δ ϭ 17.0 (7a) and 14.0 ray diffraction (Figure 2, Table 1). The molecule was found
(7b)] for the signals of these nuclei. The carbon atoms ad- to be a Z-configured phosphaalkene with a PϭC double
˚
jacent to the oxygen atoms of 7a and 7b appeared as dou- bond of 1.728(2) A between the phosphorus atom and the
blets at δ ϭ 233.8 (1JPC ϭ 86.5 Hz) and 220.3 (1JPC
69.8 Hz). Diagnostic for the mode of coordination are the ened to 1.309(2) A. The bond Al(1)ϪO(1) of 1.776(1) A
31P{1H} NMR resonances of both adducts which were ob- is quite short if compared to aluminiumϪcarbonyl oxygen
served at lower field (7a: δ ϭ 72.9 s; 7b: 78.2 s) than in 2a contacts in alane-ketone and -aldehyde adducts[15] such as
ϭ
carbonyl carbon atom. The distance C(5)ϪO(1) is length-
˚
˚
˚
and 2b. Thus, the presence of dative AlϪO bonds in 7a and the AlMe(O-2,6-tBu2-4-MeC6H2)2·OϭCPh2 [1.903(6) A]
b was inferred.
but clearly elongated relative to the AlϪO (alkoholate)
bonds in the molecule [1.733(5); 1.721(6) A].
[15]
˚
The coordination sphere at the aluminium atom is com-
pleted by one tert-butyl substituent and two chlorine atoms,
which are directed towards the diaminocarbenium center.
The trigonal-planar carbon atom C(12) of the latter forms
X-ray Structural Analysis of 7b*
Unfortunately, the initially obtained compounds 7a and
b were converted into 7a* and b* during attempts to grow
˚
a single bond of 1.844(2) A with the P-atom. Short bonds
˚
˚
N(1)ϪC(12) [1.336(2) A] and N(2)ϪC(12) [1.343(3) A] re-
flect multiple bonding between the amino groups and the
tricoordinate carbon atom. The valence angle at phos-
phorus [104.1(1)°] is comparable to that in 6b. The angle at
the planar carbon atom C(5) P(1)ϪC(5)ϪO(1) [128.4(1)] is
significantly open relative to the remaining two angles
P(1)ϪC(5)ϪC(6)
[116.0(1)°]
and
O(1)ϪC(5)ϪC(6)
[115.3(2)°]. This can be rationalized by the steric repulsion
between the cis-located substituents at the PϭC double
bond.
The atoms O(1), C(5), P(1) and C(12) are located in
nearly the same plane, as is obvious from torsion angle
C(12)ϪP(1)ϪC(5)ϪO(1) ϭ 2.4°. In contrast to the molecu-
lar structure of 6b, the ipso-carbon atom C(6) and the group
13 metal deviate from this plane [C(12)ϪP(1)Ϫ
C(5)ϪC(6) ϭ Ϫ171.6°; P(1)ϪC(5)ϪO(1)ϪAl(1) ϭ 78.8°].
Moreover, it is obvious that 6b and 7b* differ in the con-
figuration at the PϭC double bond.
Figure 2. Molecular structure of 7b* in the crystal; selected bond
˚
lengths [A] and angles [°]: P(1)ϪC(5) 1.728(2), P(1)ϪC(12)
1.844(2), O(1)ϪC(5) 1.309(2), O(1)ϪAl(1) 1.776(2), Al(1)ϪC(1)
1.969(2), Al(1)ϪCl(1) 2.173(1), Al(1)ϪCl(2) 2.170(1), C(5)ϪC(6)
1.492(3), N(1)ϪC(12) 1.336(2), N(2)ϪC(12) 1.343(2), N(1)ϪC(13)
1.465(3), N(1)ϪC(14) 1.473(2), N(2)ϪC(15) 1.472(3), N(2)ϪC(16)
1.462(3); C(5)ϪP(1)ϪC(12) 104.1(1), C(5)ϪO(1)ϪAl(1) 139.2(1),
O(1)ϪC(5)ϪC(6) 115.3(2), P(1)ϪC(5)ϪO(1) 128.4(1), P(1)Ϫ
Reaction of 2a and 2b With MMe3 (M ؍ Al, Ga, In)
The following section deals with the reactivity of the P-
acyl phosphaalkenes 2a and 2b towards the homologous
Lewis acids AlMe3, GaMe3 and InMe3 (Scheme 6).
Reaction of equimolar amounts of 2a and trimethylalu-
minium in n-pentane yielded adduct 8a as a pale-yellow
moisture-sensitive oil. The 31P{1H} NMR spectrum of the
compound displayed a singlet at δ ϭ 62.7, which is deshi-
elded by ∆δ ϭ 36.3 with respect to free 2a. Thus, the alu-
C(5)ϪC(6)
116.0(1),
P(1)ϪC(12)ϪN(1)
123.5(1),
P(1)Ϫ
C(12)ϪN(2) 116.3(1), N(1)ϪC(12)ϪN(2) 119.5(2), C(12)ϪN(1)Ϫ
C(13) 123.9(2), C(12)ϪN(1)ϪC(14) 122.3(2), C(13)ϪN(1)ϪC(14)
113.7(2), C(12)ϪN(2)ϪC(15) 123.2(2), C(12)ϪN(2)ϪC(16)
122.3(2), C(15)ϪN(2)ϪC(16) 114.3(2), O(1)ϪAl(1)ϪC(1) 114.8(1),
O(1)ϪAl(1)ϪCl(1)
C(1)ϪAl(1)ϪCl(1)
102.8(1),
110.7(1),
O(1)ϪAl(1)ϪCl(2)
C(1)ϪAl(1)ϪCl(2)
106.0(1),
111.8(1),
Cl(1)ϪAl(1)ϪCl(2) 110.4(1)
Eur. J. Inorg. Chem. 1999, 2369Ϫ2381
2373

L. Weber et al.
FULL PAPER
those already registered for 9a. As observed for 9a, adduct
10a easily lost the two molecules of Me3Ga in a vacuum.
The coordination chemistry of 2a and b towards the
“soft” Lewis base InMe3 is more straightforward (Scheme
6). The yellow solid adduct 11a and the yellow oily adduct
11b were obtained under similar conditions, and display
singlets in their 31P{1H} NMR spectra at δ ϭ 15.6 and 36.8.
A high-field coordination shift of ∆δ ϭ 10.8 for 11a, and a
low-field shift of ∆δ ϭ 5.5 is consistent with an InϪP con-
tact rather than with the alternative InϪO ligation. In the
low-field part of the 13C{1H} NMR spectrum, doublets at
δ ϭ 195.5 (1JPC ϭ 68.4 Hz) and 234.0 (1JPC ϭ 84.5 Hz)
(11a) and δ ϭ 196.2 (1JPC ϭ 76.6 Hz) and 219.9 (1JPC
ϭ
76.7 Hz) (11b) are caused by the 13C atoms of the diaminoc-
arbenium- and the carbonyl-groups, respectively. In the IR
spectrum of 11a, strong ν(CO) bands appears at ν˜ ϭ 1594
and 1546 cmϪ1, and in the spectrum of 11b, a medium in-
tense ν(CO) band at 1540 cmϪ1 with a shoulder at 1597
cmϪ1 was observed.
X-ray Structural Analysis of 10a
The crystal structure analysis of 10a shed some light on
the nature of the 1:2 adduct (Figure 3, Table 1). The back-
bone of the molecule constitutes a P-acyl unit with a trig-
onal-pyramidal P-atom (sum of angles 333.26°), which is
connected to the atoms C(4), C(12) and Ga(2) by single
˚
bonds. The bond length P(1)ϪC(4) [1.784(3) A] is shorter
˚
than P(1)ϪC(12) [1.831(3) A], which was determined to be
˚
1.800(1) A in 2b. A pronounced bond strengthening of the
PϪC(CO) bond as encountered in 6b and 7b* did not occur.
˚
The atomic distance Ga(2)ϪP of 2.635(2) A is markedly
longer than in the complex [(η5-C5Me5)(CO)2-
Scheme 6. Reaction of 2a,b with AlMe3, GaMe3 and InMe3
[16]
˚
FeP{GaMe3}C(NMe2)2] [2.503(2) A].
Generally, GaϪP
minium atom is attached to the oxygen atom of the car- bonds in molecules with tetracoordinate gallium and phos-
[17]
˚
bonyl group, as it was in the case of the adducts 7. In the phorus range from 2.347(5) A in [(Me3Si)3PǞGaI3]
up
low-field region of the 13C{1H} NMR spectrum doublets at to 2.683(5) A in [Ph2(H)PǞGa{CH2(tBu)}3].
The se-
[18][19]
˚
δ ϭ 184.4 (1JPC ϭ 76.6 Hz) and δ ϭ 233.8 (1JPC ϭ 86.5 Hz) cond molecule of GaMe3 is bound to the oxygen atom of
are readly assigned to the 13C nuclei of the CN2 and OCP the carbonyl group by a long dative bond [Ga(1)ϪO(1) ϭ
˚
˚
moieties, respectively. Signals due to the methyl groups at 2.109(2) A]. As the covalent radii of Al (1.25 A) and Ga
[20]
the metal atom were observed at δ ϭ Ϫ5.2 in the 13C NMR (1.26 A)
are similar, it is obvious from the comparison
˚
spectrum and δ ϭ Ϫ0.37 in the 1H NMR spectrum. Similar with the AlϪO contact in 7b* that only a weak gal-
results are obtained with 2b and AlMe3.
Under analogous conditions, one equivalent of trimeth-
liumϪoxygen bond is present in 10a.
The bond length of the carbonyl group [1.249(3) A] is
˚
˚
ylgallium was added to 2a and 2b. The products were a very similar to that of the P-acyl function in 2b [1.240(2) A]. The
thermolabile yellow oil (9a) and a yellow powder (9b). Both weak contact between the oxygen atom and the gallane may
compounds can easily be freed from Me3Ga in vacuum at also be inferred from the small deviation of the Ga(CH3)3
room temperature. Broad singlets in the 31P{1H} NMR unit from planarity [sum of angles C(1)ϪGa(1)ϪC(2),
spectra at δ ϭ 38.7 (9a) or δ ϭ 48.1 (9b) did not allow for C(1)ϪGa(1)ϪC(3), C(2)ϪGa(1)ϪC(3) ϭ 350.3°]. For com-
unambigious assignment of the structure to one of the parison, a more pronounced perturbation of the planar
modes of coordination under discussion. In the presence of configuration of the borane by adduct formation with 2b is
excess trimethylgallium, the NMR resonances did not shift evident by the corresponding sum of angles C(11)Ϫ
significantly. However, when the mixture of 2a and 2 equiv- B(1)ϪC(21), C(11)ϪB(1)ϪC(31) and C(21)ϪB(1)ϪC(31) of
alents of Me3Ga in n-pentane was carefully concentrated to 334.5° in 6b. In the aluminium adduct 7b*, the respective
ca 2 mL, and this solution stored for 24 h at Ϫ30°C, yellow sum of angles (332.94°) is similar to 6b. Moreover, the angle
crystals of the 1:2 adduct 10a were isolated. The NMR at the carbonyl oxygen atom opens up in going from 6b
spectra of 10a in C6D6 did not differ significantly from [130.2(2)°] through 7b* [139.2(1)°] to 10a [148.7(2)°].
2374
Eur. J. Inorg. Chem. 1999, 2369Ϫ2381

Reactivity of Carbonyl-Functionalized Phosphaalkenes
FULL PAPER
ium unit are similar to those in 6b, 7b* and 10a. Again
this group is linked to the P-atom through a single bond
˚
[P(1)ϪC(9) ϭ 1.823(8) A].
Figure 3. Molecular structure of 10a in the crystal; selected bond
˚
lengths [A] and angles [°]: P(1)ϪC(4) 1.784(3), P(1)ϪC(12)
1.831(3), P(1)ϪGa(2) 2.635(2), O(1)ϪC(4) 1.249(3), O(1)ϪGa(1)
2.109(2), C(4)ϪC(5) 1.537(3), Ga(1)ϪC(1) 1.985(3), Ga(1)ϪC(2)
1.972(3), Ga(1)ϪC(3) 1.962(3), Ga(2)ϪC(9) 1.976(3), Ga(2)ϪC(10)
1.965(3), Ga(2)ϪC(11) 1.980(3), N(1)ϪC(12) 1.337(3), N(2)ϪC(12)
1.337(3), N(1)ϪC(13) 1.465(3), N(1)ϪC(14) 1.470(3), N(2)ϪC(15)
1.462(3), N(2)ϪC(16) 1.470(3); C(4)ϪP(1)ϪC(12) 102.9(1),
C(4)ϪP(1)ϪGa(2) 127.7(1), Ga(2)ϪP(1)ϪC(12) 102.6(1), P(1)Ϫ
C(4)ϪO(1) 124.2(2), P(1)ϪC(4)ϪC(5) 118.4(2), O(1)ϪC(4)ϪC(5)
117.5(2), Ga(1)ϪO(1)ϪC(4) 148.7(2), P(1)ϪC(12)ϪN(1) 116.7(2),
Figure 4. Molecular structure of 11a in the crystal; selected bond
˚
lengths [A] and angles [°]: P(1)ϪC(4) 1.851(9), P(1)ϪC(9) 1.823(8),
P(1)ϪIn(1) 2.774(4), O(1)ϪC(4) 1.238(10), C(4)ϪC(5) 1.552(11),
N(1)ϪC(9) 1.334(10), N(2)ϪC(9) 1.374(10), N(1)ϪC(10) 1.483(10),
N(1)ϪC(11) 1.483(10), N(2)ϪC(12) 1.452(12), N(2)ϪC(13)
1.497(12), In(1)ϪC(1) 2.198(9), In(1)ϪC(2) 2.189(9), In(1)ϪC(3)
2.216(8); C(4)ϪP(1)ϪC(9) 101.2(4), C(4)ϪP(1)ϪIn(1) 125.9(3),
In(1)ϪP(1)ϪC(9) 102.3(3), P(1)ϪC(4)ϪO(1) 122.2(6), O(1)Ϫ
C(4)ϪC(5) 119.8(7), P(1)ϪC(4)ϪC(5) 118.0(6), P(1)ϪC(9)ϪN(1)
125.5(6), P(1)ϪC(9)ϪN(2) 117.3(6), N(1)ϪC(9)ϪN(2) 117.1(7),
P(1)ϪC(12)ϪN(2)
123.5(2),
N(1)ϪC(12)ϪN(2)
119.4(2),
C(12)ϪN(1)ϪC(13) 123.3(2), C(12)ϪN(1)ϪC(14) 122.3(2),
C(13)ϪN(1)ϪC(14) 113.5(2), C(12)ϪN(2)ϪC(15) 123.0(2),
C(12)ϪN(2)ϪC(16) 123.2(2), C(15)ϪN(2)ϪC(16) 113.2(2),
O(1)ϪGa(1)ϪC(1)
O(1)ϪGa(1)ϪC(3)
C(2)ϪGa(1)ϪC(3)
P(1)ϪGa(2)ϪC(9)
P(1)ϪGa(2)ϪC(11)
103.5(1),
101.1(1),
117.5(1),
107.6(1),
98.8(1),
O(1)ϪGa(1)ϪC(2)
C(1)ϪGa(1)ϪC(2)
C(1)ϪGa(1)ϪC(3)
P(1)ϪGa(2)ϪC(10)
C(9)ϪGa(2)ϪC(10)
97.0(1),
117.6(1),
115.2(1),
99.8(1),
C(9)ϪN(1)ϪC(10)
C(10)ϪN(1)ϪC(11)
C(9)ϪN(2)ϪC(13)
122.7(7),
112.7(7),
122.0(8),
C(9)ϪN(1)ϪC(11)
C(9)ϪN(2)ϪC(12)
C(12)ϪN(2)ϪC(13)
123.6(7),
124.4(8),
113.1(8),
118.8(2),
C(9)ϪGa(2)ϪC(11) 112.8(2), C(10)ϪGa(2)ϪC(11) 115.5(2)
P(1)ϪIn(1)ϪC(1) 97.6(3), P(1)-In(1)ϪC(2) 98.9(3), P(1)ϪIn(1)Ϫ
C(3) 105.5(2), C(1)ϪIn(1)ϪC(2) 115.8(4), C(2)ϪIn(1)ϪC(3)
119.9(4), C(1)ϪIn(1)ϪC(3) 114.1(3)
X-ray Structural Analysis of 11a
The X-ray structural analysis of 11a has fully confirmed
the conclusions drawn from the spectra (Figure 4, Table 1).
A trigonal pyramid configured phosphorus atom is coordi-
Reaction of 2a and 2b With
[{(Z)-cyclooctene}Cr(CO)5], [Fe2(CO)9] and
[Ni(CO)4]
˚
nated to the indium atom by a single bond of 2.774(4) A.
This value is similar to those measured in (Me3-
In)2(Ph2PCH2CH2PPh2) [2.755(4) C].[21] For indane-phos-
phane adducts InϪP bond lengths in the range of 2.575(3)
With regard to the concept of hard and soft acids and
[19a]
˚
to 2.819(2) A have been reported.
The coordination of bases, and under consideration the coordination chemistry
2a to the planar acceptor molecule InMe3 causes only a of carbonyl-stabilized ylides, the reaction of β-acyl phos-
small pyramidalization of the InC3-unit, as may be con- phaalkenes with low valent transition metal carbonyls
cluded from the sum of the angles C(1)ϪIn(1)ϪC(2), should lead to complexes with metal-phosphorus bonding.
C(1)ϪIn(1)ϪC(3) and C(2)ϪIn(1)ϪC(3) (349.8°). The en- To further substantiate this idea the phosphaalkenes 2a and
vironment of carbon atom C(4) is trigonal-planar, a CϭO
b were reacted with equimolar amounts of [{(Z)-
˚
double bond of 1.238(10) A and a CϪC single bond of cyclooctene}Cr(CO)5] for 2 h in diethyl ether (2a) or n-pen-
˚
1.552(11) A to the tert-butyl substituent clearly exclude π- tane (2b). The pentacarbonylchromium complexes 12a and
conjugation of the carbonyl group with the lone pair on 12b were isolated as yellow or orange-red microcrystalline
phosphorus in 11a. Whereas similar CϭO bond lengths solids in 79% and 71% yield, respectively.
were encountered in acyl phosphanes such as [(η5-C5Me5)-
The red microcrystalline tetracarbonyliron complexes 13a
[22]
˚
(CO)2RuϪC(O)P(tBu)(SiMe3)] [1.219(4) A]
or tBuC- and 13b (73Ϫ76% yield) resulted from the treatment of 2a
[23]
˚
(O)P(Ph)P(Ph)C(O)tBu (1.21 A),
the PϪC(CO) single and b with equimolar amounts of solid [Fe2(CO)9] in diethyl
bonds in these molecules are considerably longer [1.952(3) ether at room temperature for 18Ϫ20 h.
˚
˚
A and 1.89 A, respectively] than in 11a [P(1)ϪC(4) ϭ
Compound 2a and [Ni(CO)4] underwent reaction in di-
˚
1.851(9) A]. The structural features of the diaminocarben- ethyl ether to afford complex 14a as an orange crystalline,
Eur. J. Inorg. Chem. 1999, 2369Ϫ2381
2375

L. Weber et al.
FULL PAPER
additional donor ligand in the axial position at the trigonal
bipyramid. Intense carbonyl absorptions at ν˜ ϭ 2051, 1987,
1919 and 1900 cmϪ1 in the IR spectrum of 12a (KBr) corre-
˜
spond to the ν(CO) bands in phosphane complex 15 (ν ϭ
2051, 1989, 1927, 1894 cm
Ϫ1 [7b]). Similar absorptions occur
in compounds 12b and 13b.
.
In the IR spectra of complexes 12a, 13a, and 14a, me-
dium to intense bands at ν˜ ϭ 1584 to 1596 and 1542 to
1560 cmϪ1 are tentatively assigned to the ν(CO) modes of
the pivaloyl substituent. Thus they are found between those
of free 2a and its protonation and methylation products 3a
and 4a. For comparison, coordination of the ylides MeC-
(O)CHϭPPh3 and PhC(O)CHϭPPh3 to AuCl via the C-
atom has also led to hypsochromic shifts of the ν(CO)
Scheme 7. Complexation of 2a,b with transition metal carbonyls
bands from 1540 to 1645 and from 1500 to 1620 cmϪ1 [12]
.
extremely light-sensitive solid. Purification of this product
was effected by recrystallization from diethyl ether at
Ϫ30°C. Attempts to synthesize the analogous nickeltricar-
bonyl complex of 2b failed (Scheme 7).
X-ray Structural Analysis of 12a
An ORTEP drawing of 12a is shown in Figure 5; selected
High-field shifts of the 31P{1H} NMR resonances of bond lengths and angles are given in the caption and in
complexes 12a, 12b, 13a, 13b, and 14a in the range of δ ϭ Table 1. The molecule exhibits octahedral geometry at the
Ϫ26.4 to 1.9 are consistent with metalϪphosphorus lig- metal atom; one coordination site is occupied by an η1-
ation. In the low-field region of the 13C{1H} NMR spectra ligated phosphaalkene. The complexation of tBuC(O)Pϭ
of 12a, 13a and 14a the 13C atoms of the pivaloyl substitu- C(NMe2)2 to the [Cr(CO)5] moiety is accompanied by a sev-
ents were observed as doublets at δ ϭ 232.2 to 235.3 ere distortion of the organophosphorus ligand. A single
(1JPC ϭ 70.6 to 80.0 Hz). Doublets at δ ϭ 195.2 to 198.7 bond of 1.833(2) A is found between the trigonal pyramidal
˚
(1JPC ϭ 48.0 to 55.4 Hz) are readily assigned to the tri- phosphorus atom (sum of angles 332.9°) and the planar
coordinate carbon atoms of the carbenium building block. carbon atom C(6) (sum of angles 359.9°). Both nitrogen
Similar observations have been made in the 13C{1H} NMR atoms are also planar (sum of angles 359.9 and 358.5°). The
˚
spectra of P-benzoyl analogoues.
bond length P(1)ϪC(1) [1.848(2) A] is as long as the other
Informations on the σ-donor/π-acceptor properties of 2a PϪC single bond in the molecule. The carbon atom C(1) is
and b were provided by the IR spectra of the carbonylmetal trigonal planar configured (sum of angles 359.4°) featuring
˚
complexes. Three intense bands at ν˜ ϭ 2054, 1976 and 1966 a CϭO double bond of 1.225(2) A and a CϪC single bond
cmϪ1 in the IR spectrum of 14a (KBr) are attributed to the of 1.541(2) A to the tert-butyl substituent, which clearly
˚
stretching modes of the CO ligands of the [Ni(CO)3] moiety. excludes any significant π-conjugation between the carbonyl
The local symmetry of the latter is lower than that of the group and the lone pair on phosphorus in 12a. The CrϪP
5
˚
point group C3V. The donor capacity of the inversely polar- bond length [2.516(1) A] is similar to that in [(η -
[7a]
˚
ized phosphaalkene is similar to that of PtBu3 in [(tBu3P)- C5Me5)(CO)2FeP{Cr(CO)5}C(NMe2)2] [2.533(2) A],
but
Ni(CO)3] [ν(CO) (CH2Cl2) ϭ 2056, 1971 cmϪ1].[24] It is clearly exceeds the CrϪP atomic distances in complexes
[6a]
interesting to note that the metallophosphaalkene [(η5- such as [2,4,6-Me3C6H2P{Cr(CO)5}ϭCPh2] [2.356(1) A]
˚
[3a]
˚
C5Me5)(CO)2FePϭC(NMe2)2] of inverse electron density or [CF3P{Cr(CO)5}ϭC(F)NMe2] [2.454(1) A].
behaves as a much stronger donor ligand towards the perpendicular to the [Cr(CO)4] plane indicates an almost
[Ni(CO)3] group in [(η5-C5Me5)(CO)2FeP{Ni(CO)3}- eclipsed conformation with torsion angles C(1)ϪP(1)Ϫ
C(NMe2)2] [ν(NiCO) (KBr) ϭ 2034, 1957, 1917 cmϪ1].[7b] Cr(1)ϪC(14) ϭ 11.3° and C(6)ϪP(1)ϪCr(1)ϪC(13) ϭ
The observation of three intense carbonyl bands in the IR Ϫ11.2° (Figure 6).
A view
spectrum of the tetracarbonyliron complex 13a ranging
Presumably due to steric hindrance, the ideal local C4V-
from 2028 to 1927 cmϪ1 is consistent with the local sym- symmetry of the [Cr(CO)5] unit is slightly perturbed, as it
metry of the point group C3V for the [Fe(CO)4]-unit with an is evident from the angles C(11)ϪCr(1)ϪC(15) [86.8(1)°],
2376
Eur. J. Inorg. Chem. 1999, 2369Ϫ2381

Reactivity of Carbonyl-Functionalized Phosphaalkenes
FULL PAPER
Experimental Section
All reactions were performed by Schlenk techniques under an at-
mosphere of dry nitrogen. The phosphaalkenes Me3SiPϭC(NMe2)2
1,[25] 2a,b,[9] tBu2AlCl,[26] and the complexes [Fe2(CO)9][27] and
[{(Z)-cyclooctene}Cr(CO)5][28] were prepared as described in the
literature. [Ni(CO)4], HBF4·OEt2, MeOSO2CF3, Me3SiOSO2CF3,
(AlMe3)2, GaMe3 and InMe3 were purchased commercially. Ϫ In-
frared spectra were recorded with a Bruker FTIR IFS 66 spec-
trometer. Ϫ NMR Spectra: Bruker AC 100, AM Avance DRX 500.
Standards: SiMe4 (1H, 13C), external 85% H3PO4 (31P).
[tBuC(O)P(H)C(NMe2)2]BF4 (3a): A solution of pivaloyl chloride
(0.18 g, 1.47 mmol) in diethyl ether (10 mL) was added dropwise to
a chilled solution (Ϫ50°C) of 1 (0.30 g, 1.47 mmol) in diethyl ether
(30 mL). The reaction mixture was warmed to Ϫ20°C and stirred
for 30 min. After cooling to Ϫ50°C
a solution of 20 mL
(1.47 mmol) of ethereal HBF4 (54%) in diethyl ether (10 mL) was
added dropwise. The solution was slowly warmed to room temp.
and stirred for 1 h. A colorless precipitate was formed, filtered off
and washed with diethyl ether (20 mL) to afford 0.33 g (74% yield)
of 3a. Ϫ IR (KBr): ν˜ ϭ 1680 s, 1597 [s, (CϭO)] cmϪ1. Ϫ 1H NMR
(CD2Cl2): δ ϭ 1.18 [s, 9 H, C(CH3)3], 3.24 (s, 12 H, NCH3), 6.02
(d, JPH ϭ 245 Hz, 1 H, PH). Ϫ 13C{1H} NMR (CD2Cl2): δ ϭ 28.5
[s, C(CH3)3], 44.6 (s, NCH3), 49.9 [s, C(CH3)3], 178.1 (s, br, CN2),
Figure 5. Molecular structure of 12a in the crystal; selected bond
˚
lengths [A] and angles [°]: Cr(1)ϪP(1) 2.516(1), Cr(1)ϪC(11)
1.897(2),
Cr(1)ϪC(12)
1.889(2),
Cr(1)ϪC(13)
1.899(2),
Cr(1)ϪC(14) 1.924(2), Cr(1)ϪC(15) 1.853(2), P(1)ϪC(1) 1.848(2),
C(1)ϪO(1) 1.225(2), C(1)ϪC(2) 1.541(2), P(1)ϪC(6) 1.833(2),
C(6)ϪN(1) 1.347(2), C(6)ϪN(2) 1.339(2); N(1)ϪC(7) 1.471(2),
N(1)ϪC(8) 1.466(3), N(2)ϪC(9) 1.469(2), N(2)ϪC(10) 1.465(2),
C(2)ϪC(1)ϪP(1) 120.5(1), C(2)ϪC(1)ϪO(1) 118.0(2), P(1)ϪC(1)Ϫ
O(1) 120.9(1), C(1)ϪP(1)ϪCr(1) 130.0(1), C(1)ϪP(1)ϪC(6)
98.5(1), Cr(1)ϪP(1)ϪC(6) 104.4(1), P(1)ϪC(6)ϪN(1) 117.7(1),
P(1)ϪC(6)ϪN(2) 124.3(1), N(1)ϪC(6)ϪN(2) 118.0(2), C(6)Ϫ
N(1)ϪC(7) 123.1(2), C(6)ϪN(1)ϪC(8) 123.5(2), C(7)ϪN(1)ϪC(8)
113.3(2), C(6)ϪN(2)ϪC(9) 122.5(2), C(6)ϪN(2)ϪC(10) 123.4(1),
220.0 (s, br, CϭO); Ϫ 31P NMR (CD2Cl2): δ ϭ Ϫ53.7 (d, JPH
ϭ
245 Hz). Ϫ C10H22BF4N2OP (304.07): calcd. C 39.50, H 7.29, N
9.21; found C 39.43, H 7.03, N 9.23.
[PhC(O)P(H)C(NMe2)2]BF4 (3b): A solution of 2b was prepared
analogously from benzoyl chloride (0.26 g, 1.81 mmol) and 1
(0.37 g, 1.81 mmol) in diethyl ether (40 mL). At Ϫ50°C 0.29 g
(1.81 mmol) of ethereal HBF4 (54%) in 10 mL of the same solvent
was added dropwise. It was warmed to room temp. and stirred for
1 h. The supernatant solvent was decanted from a light-yellow oil.
The latter was kept under vacuum (10Ϫ1 Torr, 1 h) to afford 0.56 g
(95%) of 3b as a light yellow viscous oil. Ϫ IR (CsI, film): ν˜ ϭ
C(9)ϪN(2)ϪC(10)
P(1)ϪCr(1)ϪC(12)
112.6(2),
87.6(1),
P(1)ϪCr(1)ϪC(11)
P(1)ϪCr(1)ϪC(13)
90.9(1),
92.1(1),
P(1)ϪCr(1)ϪC(14) 91.1(1), P(1)ϪCr(1)ϪC(15) 177.6(1), CϪCrϪC
86.8(1)Ϫ92.4(1), CrϪCϪO 175.0(2)Ϫ178.2(2)
1
1653 (s), 1599 [s, (CϭO)] cmϪ1. Ϫ H NMR (CD2Cl2, 22°C): δ ϭ
3.34 (s, 12 H, NCH3), 6.36 (s, br, 1 H, PH), 7.55 (m, 2 H, m-PhH),
7.70 (m, 1 H, p-PhH), 7.80 (m, 2 H, o-PhH). Ϫ 1H NMR (CD2Cl2,
Ϫ70°C): δ ϭ 3.36 (s, 12 H, NCH3), 6.23 (d, JPH ϭ 257.7 Hz, 1 H,
PH), 7.65 (m, 3 H, m,p-PhH), 7.80 (m, 2 H, o-PhH). Ϫ 13C{1H}
NMR (CD2Cl2): δ ϭ 45.0 (s, NCH3), 127.0 s, 129.6 s, 135.5 s, 138.1
(d, JPC ϭ 31.8 Hz, PhC), 177.9 (s, br, CN2), 204.8 (s, br, CϭO). Ϫ
31P NMR (CD2Cl2, Ϫ70°C): δ ϭ Ϫ46.6 (d, JPH ϭ 257.1 Hz). Ϫ
C14H30BF4N2OP (324.06): calcd. C 44.48, H 5.60, N 8.64; found
C 44.38, H 5.69, N 8.40.
[tBuC(O)P(CH3)C(NMe2)2][SO3CF3] (4a): As described before, 2a
was generated from equimolar amounts of 1 (0.38 g, 1.86 mmol)
and pivaloyl chloride (0.23 g, 1.86 mmol) in 40 mL of diethyl ether.
At Ϫ50°C a solution of methyl triflate (0.31 g, 1.86 mmol) in di-
ethyl ether (10 mL) was added dropwise to the mixture, thereafter
it was warmed to room temp. and stirred for 1 h. The orange pre-
cipitate formed was filtered off and washed with diethyl ether
(30 mL) to give 0.53 g (75% yield) of 5a as a moisture-sensitive
solid. Ϫ IR (KBr): ν˜ ϭ 1644 s, 1588 [s, (CϭO)] cmϪ1. Ϫ 1H NMR
(CD2Cl2): δ ϭ 1.20 [s, 9 H, C(CH3)3], 1.69 (d, JPH ϭ 4.5 Hz, 3 H,
PCH3), 3.32 (s, 12 H, NCH3). Ϫ 13C{1H} NMR (CD2Cl2): δ ϭ 6.0
(d, JPC ϭ 13.3 Hz, PCH3), 26.4 [s, C(CH3)3], 45.2 (s, NCH3), 49.8
[d, JPC ϭ 30.4 Hz, C(CH3)3], 121.2 (q, JCF ϭ 321.0 Hz, CF3], 177.6
(d, JPC ϭ 44.0 Hz, CN2), 222.7 (d, JPC ϭ 60.6 Hz, CϭO). Ϫ
Figure 6. Newman projection of 12a along the Cr(1)ϪP(1) vector
P(1)ϪCr(1)ϪC(13) [92.1(1)°] and C(11)ϪCr(1)ϪC(13)
[174.6(1)°]. It is also remarkable that one of the equatorial
˚
CrϪC(CO) bonds [Cr(1)ϪC(14) ϭ 1.924(2) A] is elongated
in comparison to the remaining equatorial carbonyl ligands 31P{1H} NMR: δ ϭ Ϫ3.8 s. Ϫ C12H24F3N2O4PS (380.36): calcd. C
˚
37.89, H 6.36, N 7.36; found C 36.62, H 5.82, N 7.34.
[CrϪCO ϭ 1.889(2) to 1.899(2) A]. As usual in [Cr(CO)5]
complexes with donor ligands, the axial CrϪCO bond is
markedly shortened [Cr(1)ϪC(15) ϭ 1.853(2) A]
[PhC(O)P(CH3)C(NMe2)2][SO3CF3] (4b): A solution of 2b, pre-
pared from 1 (0.32 g, 1.57 mmol) and benzoyl chloride (0.22 g,
˚
Eur. J. Inorg. Chem. 1999, 2369Ϫ2381
2377

L. Weber et al.
FULL PAPER
1.57 mmol) in 40 mL of diethyl ether was treated with methyl tri-
to a solution of 2b (0.30 g, 1.28 mmol) in toluene (40 mL). After
flate (0.25 g, 1.57 mmol) in diethyl ether (10 mL) at Ϫ50°C and 30 min of stirring the formation of a yellow precipitate began. After
then allowed to warm to room tmperature with stirring. A pale
orange solid formed, which was filtered off and washed with diethyl
3 h the precipitate was filtered and washed with n-pentane (5 mL)
to yield 0.72 g (75%) of 6b as a yellow solid. Ϫ 1H NMR (CD2Cl2):
ether (30 mL) to afford 0.56 g (89%) of 4b. Ϫ IR (CsI): ν˜ ϭ 1647 δ ϭ 2.86 (s, 12 H, NCH3), 7.31 (m, 3 H, PhH), 7.39 (m, 2 H, PhH).
m, 1587 [m, (CϭO)] cmϪ1. Ϫ 1H NMR (CD2Cl2): δ ϭ 1.78 (d, 13C{1H} NMR (CD2Cl2): δ ϭ 44.6 (s, NCH3), 127.4 (s, PhC),
JPH ϭ 3.7 Hz, PCH3), 3.16 (s, 12 H, NCH3), 7.57 (m, 3 H, PhH), 128.9 (s, PhC), 131.2 (s, PhC), 137.0 (d, JCF ϭ 245.8 Hz, aryl-C),
7.74 (m, 2 H, PhH). Ϫ 13C{1H} NMR (CD2Cl2): δ ϭ 5.0 (d, JPC ϭ 139.8 (d, JCF ϭ 246.9 Hz, aryl-C), 140.0 (s, PhC), 148.3 (d, JCF
Ϫ
ϭ
11.7 Hz, PCH3), 44.6 (s, NCH3), 121.1 (q, JCF ϭ 321.2 Hz, CF3),
238.0 Hz, aryl-C), 148.6 (d, JCF ϭ 239.1 Hz, aryl-C), 190.9 (d,
127.2 (d, JPC ϭ 6.9 Hz, PhC), 129.7 s, 136.0 s, 138.1 (d, JPC
35.9 Hz, PhC), 177.5 (d, JPC ϭ 39.4 Hz, CN2), 210.0 (d, JPC
ϭ
JCP ϭ 80.6 Hz, CN2), 223.4 (d, JCP ϭ 71.9 Hz, PCO). Ϫ 31P{1H}
NMR: δ ϭ 72.6 (s). Ϫ C30H17BF15N2OP (728.23): calcd. C 48.16,
ϭ
37.7 Hz, CϭO). Ϫ 31P{1H} NMR (CD2Cl2): δ ϭ Ϫ2.3 s. Ϫ H 2.29, N 3.74; found C 48.12, H 2.08, N 3.73.
C14H20F3N2O4PS (400.35): calcd. C 42.00, H 5.04, N 7.00; found
C 42.00, H 5.00, N 6.70.
tBuC[OAl(tBu)2Cl]؍PC(NMe2)2 (7a): 15.7 mL of a 0.1 solution
of tBu2AlCl in toluene (1.57 mmol) was added dropwise at Ϫ40°C
to a freshly prepared solution of 2a (0.37 g, 1.57 mmol) in 40 mL
of toluene. While warming to room temp. the color of the solution
changed from yellow to orange. After 1 h of stirring the solvent
was removed in vacuo and the oily residue was extracted with n-
pentane (5 ϫ 10 mL) to give 7a as an orange, very moisture- and
air-sensitive solid. Attempts to crystallize 7a led to dismutation. A
few crystals of tBuC[OAl(tBu)Cl2]ϭPC(NMe2)2 (7a*) were ob-
tained after storing a solution of pure 7a in C6D6 at ϩ6°C for 3
[tBuC(OSiMe3)؍PC(NMe2)2][SO3CF3] (5a): A solution of 2a, ob-
tained from 1 (0.28 g, 1.37 mmol) and pivaloyl chloride (0.17 g,
1.37 mmol) in 40 mL of diethyl ether was treated at Ϫ50°C with a
solution of trimethylsilyl triflate (0.30 g, 1.37 mmol) in diethyl ether
(10 mL). Thereafter it was warmed to room temp. whereupon a
pale yellow oil separated. The solvent was decanted, and the re-
maining oil was kept in vacuo (10Ϫ2 Torr) for 1 h to afford 0.53 g
(88% yield) of 5a as a viscous, very air- and moisture-sensitive
liquid. Ϫ IR (CsI, film): ν˜ ϭ 1221 [m, δ(SiMe3)], 836 [m, ρ(SiMe3)]
1
weeks. Ϫ 7a: H NMR (C6D6): δ ϭ 1.34 [s, 9 H, (CH3)3CC], 1.38
1
cmϪ1. Ϫ H NMR (CD2Cl2): δ ϭ 0.33 (s, 9 H, SiCH3), 1.24 [s, 9
[s, 18 H, (CH3)3CAl], 2.63 (s, 12 H, NCH3). Ϫ 13C{1H} NMR
H, C(CH3)3], 3.33 (s, 12 H, NCH3). Ϫ 13C{1H} NMR (CD2Cl2):
δ ϭ 1.7 (s, SiCH3), 28.5 [s, C(CH3)3], 45.0 (s, NCH3), 51.1 [s, br,
C(CH3)3], 121.2 (q, JCF ϭ 321.3 Hz, CF3), 180.8 (d, JPC ϭ 75.5 Hz,
CN2), 226.1 (d, JPC ϭ 77.3 Hz, PCO). Ϫ 31P{1H} NMR (CD2Cl2):
δ ϭ 109.2 s. Ϫ C14H30F3N2O4PSSi (438.52): calcd. C 38.35, H 6.90,
N 6.39; found C 36.91, H 6.36, N 6.44.
(CD2Cl2): δ ϭ 29.4 [s, CC(CH3)3], 31.6 [s, AlC(CH3)3], 44.2 (s,
1
NCH3), 46.3 [d, JPC ϭ 35.5 Hz, CC(CH3)3], 184.4 (d, JPC
ϭ
76.5 Hz, CN2), 233.8 (d, JPC ϭ 86.5 Hz, PCO), the signal of
AlC(CH3)3 was not detectable. Ϫ 31P{1H} NMR (CD2Cl2): δ ϭ
72.9 (s). Ϫ C18H39AlClN2OP (392.92): calcd. C 55.02, H 10.01, N
7.13; found C 54.89, H 10.13, N 7.05. Ϫ 7a*: C14H30AlCl2N2OP
(371.26): calcd. C 45.29, H 8.14, N 7.55; found 45.27, H 8.16, N
7.36.
PhC(OSiMe3)؍PC(NMe2)2][SO3CF3] (5b): A solution of 2b, pre-
pared from 1 (0.25 g, 1.23 mmol) and benzoyl chloride (0.17 g,
1.23 mmol), in 40 mL of diethyl ether was treated with a solution
of 0.27 g (1.23 mmol) of trimethylsilyl triflate in the same solvent
(10 mL) at Ϫ50°C. It was warmed to room temp., whereupon a
colorless oil separated. Decanting the solvent and liberating the oil
from volatile compounds in vacuo (10Ϫ2 Torr) gave 0.48 g of 5b as
an extremely air- and moisture-sensitive colorless oil. Ϫ IR (CsI,
film): ν˜ ϭ 1223 [m, δ(SiMe3)], 839 [m, ρ(SiMe3)] cmϪ1. Ϫ 1H NMR
(CD2Cl2): δ ϭ 0.15 (s, 9 H, SiCH3), 3.39 (s, 12 H, NCH3), 7.42 (m,
3 H, PhH), 7.59 (m, 2 H, PhH). Ϫ 13C{1H} NMR (CD2Cl2): δ ϭ
0.8 (s, SiCH3), 45.1 (s, NCH3), 127.1 s, 129.5 s, 139.5 (s, PhC),
181.0 (d, JPC ϭ 72.4 Hz, CN2), 211.3 (d, JPC ϭ 61.4 Hz, PCO). Ϫ
31P{1H} NMR (CD2Cl2): δ ϭ 101.0 s. Ϫ C16H26F3N2O4PSSi
(458.51): calcd. C 41.91, H 5.72, N 6.11; found C 40.14, H 5.55,
N 6.59.
PhC[OAl(tBu)2Cl]؍PC(NMe2)2 (7b): Analogously, reaction of 2b
(0.34 g, 1.42 mmol) and tBu2AlCl (14.2 mL of a 0.1 solution in
toluene, 1.42 mmol) in 40 mL of toluene led to the orange solid 7b
(0.38 g, 64%). Attempts to grow single crystals of 7b from C6D6 at
6°C resulted in a dismutation and the isolation of a few crystals of
PhC[OAl(tBu)Cl2]ϭPC(NMe2)2 (7b*) after 2 weeks. Ϫ 7b: 1H
NMR (C6D6): δ ϭ 1.37 [s, 18 H, C(CH3)3], 2.63 (s, 12 H, NCH3),
7.09 (m, 3 H, PhH), 8.07 (m, 2 H, PhH). Ϫ 13C{1H} NMR
(CD2Cl2): δ ϭ 29.7 [s, C(CH3)3], 31.3 [s, C(CH3)3], 44.1 (s, NCH3),
125.5 s, 128.7 s, 131.7 s, 143.5 (d, JPC ϭ 39.0 Hz, PhC), 185.3 (d,
JPC ϭ 71.8 Hz, CN2), 220.3 (d, JPC ϭ 69.8 Hz, PCO). Ϫ 31P{1H}
NMR (CD2Cl2): δ ϭ 78.2 (s). Ϫ C20H35AlClOP (412.92): calcd C
58.18, H 8.54, N 7.78; found C 57.50, H 8.04, N 8.20.
tBuC(OAlMe3)؍PC(NMe2)2 (8a): At Ϫ30°C 13.2 mL of a 0.1
solution of AlMe3 in n-hexane (1.32 mmol) was added dropwise to
a solution of 2a (0.29 g, 1.32 mmol) in n-pentane (40 mL). The yel-
low color of the solution faded rapidly as it warmed up. The solvent
was then removed in vacuo to leave 8a as a pale-yellow very air-
tBuC[OB(C6F5)3]؍PC(NMe2)2 (6a): A 10% solution of tris(pen-
tafluorophenyl)borane (5.52 g, 1.08 mmol) in toluene was added
dropwise to a chilled solution (Ϫ30°C) of 2a (0.23 g, 1.08 mmol)
in toluene (40 mL). The mixture was slowly warmed to room temp.,
whereupon the slow formation of a precipitate occurred. After 3 h
of stirring the bright yellow solid was filtered and washed with
1
and moisture-sensitive oil. Ϫ H NMR (C6D6): δ ϭ Ϫ0.37 (s, 9H,
AlCH3), 1.39 [s, 9 H, C(CH3)3], 2.50 (s, 12 H, NCH3). Ϫ 13C{1H}
NMR (CD2Cl2): δ ϭ Ϫ5.2 (s, AlCH3), 28.5 [s, C(CH3)3], 43.6 (s,
NCH3), 46.3 [d, JCP ϭ 34.7 Hz, C(CH3)3], 189.9 (d, JCP ϭ 78.3 Hz,
CN2), 239.6 (d, JCP ϭ 86.4 Hz, PCO). Ϫ 31P{1H} NMR (CD2Cl2):
δ ϭ 62.7 (s). Ϫ C13H30AlN2OP (288.41): calcd. C 54.14, H 10.48,
N 9.71; found C 53.48, H 10.42, N 9.49.
1
5 mL of n-pentane. Yield: 0.52 g (66%) of yellow 6a. Ϫ H NMR
(CD2Cl2): δ ϭ 1.13 [s, 9 H, C(CH3)3], 3.13 (s, 12 H, NCH3). Ϫ
13C{1H} NMR (CD2Cl2): δ ϭ 28.8 [s, C(CH3)3], 45.4 (s, NCH3),
48.4 [s, C(CH3)3], 137.0 (d, JCF ϭ 247.7 Hz, aryl-C), 139.5 (d,
JCF ϭ 247.2 Hz, aryl-C), 147.5 (d, JCF ϭ 237.9 Hz, aryl-C), 147.9
(d, JCF ϭ 240.1 Hz, aryl-C), 188.5 (d, JCP ϭ 89.0 Hz, CN2), 228.8
(d, JCP ϭ 81.4 Hz, PCO). Ϫ 31P{1H} NMR (CD2Cl2): δ ϭ 68.3 s. Ϫ
C28H21BF15N2OP (728.24): calcd. C 46.18, H 2.91, N 3.85; found C
46.16, H 3.03, N 3.81.
PhC(OAlMe3)؍PC(NMe2)2 (8b): Similarly, 0.31 g (90%) of 8b was
obtained as an orange air- and moisture-sensitive oil from
1.12 mmol of AlMe3 and 0.26 g (1.12 mmol) of 2b. Ϫ 1H NMR
(C6D6): δ ϭ Ϫ0.33 (s, 9H, AlCH3), 2.47 (s, 12H, NCH3), 7.12 (m,
PhC[OB(C6F5)3]؍PC(NMe2)2 (6b): A 10% solution of B(C6F5)3
(6.56 g, 1.28 mmol) in toluene was added dropwise at room temp. 3H, PhH), 8.23 (m, 2H, PhH). Ϫ 13C{1H} NMR (CD2Cl2): δ ϭ
2378
Eur. J. Inorg. Chem. 1999, 2369Ϫ2381

Reactivity of Carbonyl-Functionalized Phosphaalkenes
FULL PAPER
Ϫ5.7 (s, AlCH3), 43.5 (s, NCH3), 125.6 (s, PhC), 131.7 (s, PhC),
(s, 12 H, NCH3), 7.13 (m, 3 H, PhH), 8.26 (m, 2 H, PhH). Ϫ
2
1
143.0 (d, JCP ϭ 40.4 Hz, i-PhC), 189.9 (d, JCP ϭ 76.3 Hz, CN2), 13C{1H} NMR (CD2Cl2): δ ϭ Ϫ4.7 (s, InCH3), 42.2 (s, NCH3),
1
223.5 (d, JCP ϭ 73.4 Hz, PCO). Ϫ 31P{1H} NMR (CD2Cl2): δ ϭ 126.4 s, 131.1 s, 133.0 s, 144.6 (d, JCP ϭ 46.7 Hz, PhC), 196.2 (d,
64.9 s. Ϫ C15H26N2AlOP (308.40): calcd. C 58.42, H 8.50, N 9.08; JCP ϭ 76.6 Hz, CN2), 219.9 (d, JCP ϭ 76.7 Hz, PCO). Ϫ 31P{1H}
due to the extreme sensibility of 8b no reliable elemental analyses
NMR (CD2Cl2): δ ϭ 36.8 (s). Ϫ C15H26InN2OP (396.17): calcd. C
could be obtained.
45.48, H 6.61, N 7.07; found C 44.27, H 6.56; N 6.65.
tBuC(O)PC(NMe2)2·GaMe3 (9a): At Ϫ30°C 11.5 mL of a 0.1
solution of GaMe3 in n-hexane (1.15 mmol) was added dropwise
to a solution of 2a (0.25 g, 1.15 mmol) in n-pentane (40 mL). After
warm up to ambient temp. the solvent was carefully removed in
vacuo to afford 9a (0.32 g, 84%) as a yellow, very moisture- and
air-sensitive oil. In vacuo (10Ϫ3 Torr) the adduct can be liberated
completely from GaMe3. Ϫ 1H NMR (C6D6): δ ϭ 0.08 (s, 9 H,
GaCH3), 1.37 [s, 9 H, C(CH3)3], 2.46 (s, 12 H, NCH3). Ϫ 13C{1H}
NMR (CD2Cl2): δ ϭ Ϫ2.0 (s, GaCH3), 28.2 [s, C(CH3)3], 42.9 (s,
NCH3), 47.1 [d, JCP ϭ 38.6 Hz, C(CH3)3], 195.6 (d, JCP ϭ 76.3 Hz,
CN2), 237.3 (d, JCP ϭ 88.8 Hz, PCO). Ϫ 31P{1H} NMR (CD2Cl2):
δ ϭ 38.7 (s, br). Ϫ C13H30GaN2OP (331.09): calcd. C 47.16, H
9.13, N 8.46; found C 45.21, H 8.52, N 8.06.
[tBuC(O)P{Cr(CO)5}C(NMe2)2] (12a):
A solution of [{(Z)-
cyclooctene}Cr(CO)5] (0.33 g, 1.08 mmol) in 10 mL of diethyl ether
was added dropwise to a chilled solution (Ϫ30°C) of 1.08 mmol of
2a, prepared in situ from 0.13 g of pivaloyl chloride and 0.22 g of
1, in 40 mL of diethyl ether. The solution was warmed to room
temp. and was stirred for 2 h. Evaporation to dryness afforded 12a
as a yellow solid, which was crystallized from toluene at Ϫ30°C
(Yield 0.35 g, 79%). Ϫ IR (KBr): ν˜ ϭ 2051 [m, (CrCO)], 1987 [m,
(CrCO)], 1919 [s, (CrCO)], 1900 [s, (CrCO)], 1584 [m, (CO)acyl],
1553 [m, (CO)acyl] cmϪ1. Ϫ 1H NMR (C6D6): δ ϭ 1.34 [s, 9 H,
C(CH3)3], 2.42 (s, br, 12 H, NCH3). Ϫ 13C{1H} NMR (C6D6): δ ϭ
27.9 [s, C(CH3)3], 43.2 [s, NCH3], 48.4 [d, JPC ϭ 40.8 Hz, C(CH3)3],
198.7 (d, JPC ϭ 48.0 Hz, CN2), 218.2 (s, CrCOeq), 225.1 (s,
CrCOax), 235.3 (d, JPC ϭ 75.2 Hz, PCO). Ϫ 31P{1H} NMR (C6D6):
δ ϭ Ϫ12.8 (s). Ϫ C15H21CrN2O6P (408.31): calcd. C 44.12, H 5.18,
N 6.86; found: C 44.10, H 4.93, N 6.78.
tBuC(O)PC(NMe2)2·2GaMe3 (10a):
Analogously, 23.0 mL
(2.30 mmol) of a 0.1 solution of GaMe3 in n-hexane was reacted
with 0.25 g (1.15 mmol) of 2a in 40 mL of n-pentane. After warm-
ing to room temp. the mixture was concentrated to 2 mL and stored
at Ϫ30°C for 24 h, whereupon yellow crystalline 10 (0.24 g, 63%)
separated. The air- and moisture-sensitive adduct can be freed from
GaMe3 in vacuo. The chemical shifts in the NMR spectra of 10a
are essentially the same as of 9a Ϫ a phenomenon, which is pre-
sumeably caused by dissociation.
[PhC(O)P{Cr(CO)5}C(NMe2)2] (12b):
A
solution of [{Z)-
cyclooctene}Cr(CO)5] (0.43 g, 1.42 mmol) in n-pentane (10 mL)
was added dropwise to a chilled solution (Ϫ40°C) of 2b, prepared
in situ from 0.29 g (1.42 mmol) of 1 and 0.20 g (1.42 mmol) of ben-
zoyl chloride, in 40 mL of n-pentane. The suspension was slowly
warmed to room temp. whereupon its color changed from yellow
to orange-red. Solvent and volatile components were removed in
vacuo, and the residue was washed with cold n-pentane
(2 ϫ 10 mL, Ϫ30°C) to afford 0.43 g (71% yield) of 12b as an or-
ange-red microcrystalline solid. Ϫ IR (KBr): ν˜ ϭ 2051 [vs, (CrCO)],
1929 [vs, (CrCO)], 1900 [vs, (CrCO)], 1564 [sh, (CO)acyl], 1545 [m,
PhC(O)PC(NMe2)2·GaMe3 (9b): A 0.1 solution of GaMe3 in n-
hexane (7.8 mL, 0.78 mmol) was added dropwise to a cooled solu-
tion of 2b (0.18 g, 0.78 mmol) in n-pentane (40 mL). After warming
to ambient temp. the solvent was carefully removed in vacuo. Ad-
duct 9b (0.25 g, 91% yield) was obtained as an extremely air- and
moisture-sensitive residue. Continued evacuation led to a complete
removal of GaMe3. Ϫ 1H NMR (C6D6): δ ϭ 0.05 (s, 9 H, GaCH3),
2.47 (s, 12 H, NCH3), 7.13 (m, 3 H, PhH), 8.19 (m, 2 H, PhH). Ϫ
13C{1H} NMR (CD2Cl2): δ ϭ Ϫ2.2 (s, GaCH3), 43.1 (s, NCH3),
126.7 s, 126.8 s, 133.0 s, 144.3 (d, JCP ϭ 43.9 Hz, PhC), 194.0 (d,
JCP ϭ 79.5 Hz, CN2), 225.4 (d, JPC ϭ 76.7 Hz, PCO). Ϫ 31P{1H}
NMR (CD2Cl2): δ ϭ 48.1 (s, br). Ϫ C15H26GaN2OP (351.08):
calcd.C 51.32, H 7.46, N 7.98; found C 49.80, H 7.52, N 7.75.
1
(CO)acyl] cmϪ1. Ϫ H NMR (CD2Cl2): δ ϭ 3.01 (s, 12 H, NCH3),
7.42 (m, 2 H, PhH), 7.48 (m, 1 H, PhH), 7.68 (m, 2 H, PhH). Ϫ
13C{1H} NMR (CD2Cl2): δ ϭ 43.8 (s, NCH3), 127.4 s, 128.6 s,
132.0 s, 142.7 (d, JCP ϭ 12.6 Hz, PhC), 202.0 (d, JCP ϭ 52.3 Hz,
CN2), 218.2 [s, Cr(CO)eq], 222.0 (d, JCP ϭ 40.6 Hz, PCO), 225.4 [s,
Cr(CO)ax].
Ϫ δ ϭ 1.9 (s). Ϫ
31P{1H} NMR (CD2Cl2):
C17H17CrN2O6P (428.30): calcd. C 47.67, H 4.00, 6.54; found C
47.64, H 4.08, N 6.46.
[tBuC(O)P{Fe(CO)4}C(NMe2)2] (13a): Solid [Fe2(CO)9] (0.50 g,
1.37 mmol) was added to a solution of 1.37 mmol of 2a, prepared
in situ from 1 (0.28 g) and pivaloyl chloride (0.17 g), in 40 mL of
diethyl ether at Ϫ30°C. The mixture was allowed to warm to ambi-
ent temp. and stirring was continued for 18 h. The solution changed
color from orange to red. It was evaporated to dryness to give 13a
as a red powder, which was crystallized from diethyl ether at
Ϫ30°C. (Yield: 0.38 g, 73%). Ϫ IR (KBr): ν˜ ϭ 2028 [s, (FeCO)],
1943 [s,(FeCO)], 1927 [s, (FeCO)], 1596 [s, (CO)acyl], 1560 [m,
(CO)acyl] cmϪ1. Ϫ 1H NMR (C6D6): δ ϭ 1.41 [s, 9 H, C(CH3)3],
2.43 (s, 12 H, NCH3). Ϫ 13C{1H}NMR (C6D6): δ ϭ 28.0 [s,
C(CH3)3], 43.3 (s, NCH3), 49.0 [d, JPC ϭ 42.0 Hz, C(CH3)3], 195.2
(d, JPC ϭ 55.4 Hz, CN2), 217.0 (s, FeCO), 235.3 (d, JPC ϭ 80.0 Hz,
tBuC(O)P(InMe3)C(NMe2)2 (11a): Analogously, a 0.1 solution of
InMe3 in n-hexane (9.6 mL, 0.96 mmol) was added atϪ40°C drop-
wise to a solution of 2a (0.21 g, 0.96 mmol) in 40 mL of n-pentane.
The mixture was slowly warmed up to room temp. and the solvent
was carefully removed in vacuo. Crude adduct 11a was obtained as
a yellow oily residue, which was redissolved in n-pentane (5 mL)
and stored at Ϫ30°C. Pure 11a was isolated as orange crystals
(0.29 g, 80%). Ϫ IR (KBr): ν˜ ϭ 1594 (s, CO), 1546 (s, CO) cmϪ1
1H NMR (C6D6): δ ϭ 0.09 (s, br, 9 H, InCH3), 1.36 [s, 9 H,
C(CH3)3], 2.45 (s, 12 H, NCH3). Ϫ 13C{1H} NMR (CD2Cl2): δ ϭ
Ϫ4.6 (s, InCH3), 27.9 [s, C(CH3)3], 43.1 (s, NCH3), 47.7 [d, JCP
.
Ϫ
ϭ
39.8 Hz, C(CH3)3], 195.5 (d, JCP ϭ 68.4 Hz, CN2), 234.0 (d, JCP ϭ
84.5 Hz, PCO). Ϫ 31P{1H} NMR (CD2Cl2): δ ϭ 15.6 (s, br). Ϫ
C13H30InN2OP (376.18): calcd. C 41.51, H 8.04, N 7.45; found C
41.16, H 8.21, N 7.41.
1
PCO). Ϫ P{1H}NMR (C6D6): δ ϭ Ϫ26.4 (s). Ϫ C15H21FeN2O5P
(384.15): calcd. C 43.77, H 5.51, N 7.29; found C 43.65, H 5.60,
N 7.23.
PhC(O)P(InMe3)C(NMe2)2 (11b): Adduct 11b (0.40 g, 91%) was
isolated as an air- and moisture-sensitive solid from the reaction of
InMe3 (1.12 mmol of a 0.1 solution in n-hexane, 11.2 mL,) and
[PhC(O)P{Fe(CO)4}C(NMe2)2] (13b): Analogously, red microcrys-
talline 13b (0.48 g, 76% yield) was prepared from 1.57 mmol of 2b,
2b (0.28 g, 1.12 mmol) in 40 mL of n-pentane at Ϫ30°C and after obtained in situ from 1 (0.32 g) and benzoyl chloride (0.22 g), and
an analogous workup. Ϫ IR (KBr): ν˜ ϭ 1597 (sh, CO), 1540 (m, 0.57 g (1.57 mmol) of [Fe2(CO)9] in 40 mL of diethyl ether at room
CO) cmϪ1. Ϫ H NMR (C6D6): δ ϭ 0.06 (s, br, 9 H, InCH3), 2.53 temp. over a period of 20 h. Ϫ IR (KBr): ν˜ ϭ 2031 [s, (FeCO)],
1
Eur. J. Inorg. Chem. 1999, 2369Ϫ2381
2379

L. Weber et al.
FULL PAPER
Table 2. Crystallographic data for 6b, 7b*, 10a, 11a and 12a
6b
7b*
10a
11a
12a
formula
color
C30H17BF15N2OP
yellow
C16H26AlCl2N2OP
yellow
C16H39Ga2N2OP
yellow
C13H30InN2OP
yellow
C15H21CrN2O6P
yellow
size (mm3)
Mr
0.68 ϫ 0.53 ϫ 0.16
748.24
1.1 ϫ 0.6 ϫ 0.3
391.24
1.2 ϫ 0.8 ϫ 0.5
445.90
0.7 ϫ 0.5 ϫ 0.2
376.18
0.8 ϫ 0.4 ϫ 0.4
408.31
¯
¯
¯
¯
space group
a (C)
Pbca
P1
P1
P1
P1
18.8661(3)
14.1381(3)
23.9734(5)
10.071(4)
10.665(2)
10.635(5)
82.51(3)
68.94(3)
76.47(2)
1035.0(7)
1.255
9.651(5)
10.259(7)
12.758(7)
85.64(5)
74.57(4)
70.61(5)
1148.5(12)
1.289
9.712(8)
10.076(10)
10.033(7)
96.11(7)
94.70(6)
105.85(7)
932.8(14)
1.339
9.500(3)
9.738(3)
11.394(3)
80.36(2)
86.83(3)
68.82(2)
969.0(5)
1.399
b (C)
c (C)
α (°)
β (°)
γ (°)
3
˚
V (A)
6394.4(2)
1.554
8
ρcalcd (g cmϪ3
Z
)
2
2
2
2
F (000)
2992
412
468
388
424
µ (mmϪ1
)
0.202
4.0 < 2θ < 56.6
293
0.438
2.419
1.347
0.704
2θ range (°)
T (K)
4.0 < 2θ < 60.0
173
4.0 < 2θ < 60.0
173
4.0 < 2θ < 50.0
173
3.0 < 2θ < 60.0
173
refl. measured
unique refl.
53084
6436
6335
7053
3501
6147
6020
6685
3281
5645
abs. refl. (I) > 2σ(I)
parameters
4316
4507
5227
2321
4530
451
215
212
173
233
Ϫ3
˚
max. resid. dens., e A
0.44
0.34
0.86
1.16
0.32
[a]
R1
0.062
0.146
0.044
0.044
0.068
0.038
[a]
wR2
0.114
0.107
0.172
0.091
R ϭ Σ(ԽԽFoԽ Ϫ ԽFcԽԽ)/ΣԽFoԽ; Rw ϭ {Σ[w(Fo Ϫ Fc2)2]/Σ[w(Fo2)2]}0·5; R1 for abs. data, weighted for all data on F2.
[a]
2
1913 [vs, (FeCO)], 1603 [s, (CO)acyl], 1550 [m, (CO)acyl] cmϪ1. Ϫ rections using ψ-scans were applied. Crystallographic programs
1H NMR (C6D6): δ ϭ 2.41 (s, 12 H, NCH3), 7.13 (m, 3 H, PhH), used for structure solutions and refinements were SHELXTL
8.03 (m, 2 H, PhH). Ϫ 13C{1H} NMR (C6D6): δ ϭ 43.9 (s, NCH3), PLUS and SHELXL-97. The structures were solved by direct meth-
127.8 (s), 128.6 (s), 132.2 (s), 141.6 (d, JCP ϭ 43.9 Hz, PhC), 195.6 ods and refined by using full-matrix least squares on F2 and all
(d, JCP ϭ 56.1 Hz, CN2), 216.2 (s, FeCO), 221.9 (d, JCP ϭ 56.5 Hz, unique reflections and attributing anisotropic thermal parameters
PCO). Ϫ 31P{1H} NMR (C6D6): δ ϭ Ϫ13.6 (s). Ϫ C16H11FeN2O5P
(404.14): calcd. C 47.55, H 4.24, N 6.93; found C 47.52, H 4.08,
N 6.54.
to all non-hydrogen atoms. Hydrogen atoms were included at calcu-
lated positions using a riding model.[29] Crystal data collection and
refinement parameters are given in Table 2. ORTEP drawings of
the solid state structures of 6b, 7b*, 10a, 11a and 12a are shown in
Figures 1Ϫ6. Bonding parameters are given in the captions and
in Table1.
[tBuC(O)P{Ni(CO)3}C(NMe2)2] (14a): A solution of [Ni(CO)4]
(0.23 g, 1.37 mmol) in 10 mL of diethyl ether was added dropwise
to the chilled solution (Ϫ30°C) of 1.37 mmol 2a, prepared from
0.28 g 1 and 0.17 g of pivaloyl chloride, in diethyl ether (30 mL).
The mixture was allowed to warm to room temp. and was stirred
for 1 h, whereupon its color changed from orange to red-brown.
Volatile components were removed in vacuo, and the red solid resi-
due was washed with 20 mL of cold n-pentane (Ϫ30°C). Recrystal-
lization from diethyl ether afforded orange crystalline 14a (0.26 g,
50%). Upon exposure to daylight, the crystals turned brown rap-
idly. Ϫ IR (KB): ν˜ ϭ 2054 [s, (NiCO)], 1976 [s, (NiCO)], 1966 [s,
Acknowledgments
This work was financially supported by the Fonds der Chemischen
Industrie, Frankfurt/Main, and the Deutsche Forschungsgemein-
schaft, Bonn, which are gratefully acknowledged.
[1]
[1a] Multiple Bonds and Low Coordination in Phosphorus Chemis-
1
(NiCO)], 1584 [s, (CO)acyl], 1542 [m, (CO)acyl] cmϪ1. Ϫ H NMR
try (Eds.: M. Regitz, O. J. Scherer), Thieme, Stuttgart 1990. Ϫ
(C6D6): δ ϭ 1.38 [s, 9 H, C(CH3)3], 2.53 (s, 12 H, NCH3). Ϫ
[1b]
K. B. Dillon, F. Mathey, J. F. Nixon, Phosphorus: The Car-
13C{1H}NMR (C6D6): δ ϭ 27.6 [s, C(CH3)3], 42.5 (s, NCH3), 48.1
bon Copy, Wiley, Chichester 1998.
[2] [2a]
[d, JPC ϭ 41.5 Hz; C(CH3)3], 196.7 (s, NiCO), 198.4 (d, JPC
ϭ
E. P. O. Fuchs, H. Heydt, M. Regitz, W. W. Schoeller, T.
Busch, Tetrahedron Lett. 1989, 30, 5111Ϫ5114. Ϫ [2b] E. Fuchs,
B. Breit, H. Heydt, W. W. Schoeller, T. Busch, C. Krüger, P.
Betz, M. Regitz, Chem. Ber. 1991, 124, 2843Ϫ2855.
48.9 Hz, CN2), 232.2 (d, JPC ϭ 70.6 Hz, PCO). Ϫ 31P{1H}NMR
(C6D6): δ ϭ Ϫ11.7 (s). Ϫ C13H21N2NiO4P (358.99): calcd. C 43.50,
H 5.90, N 7.80; found C 43.47, H 5.80, N 7.79.
[3] [3a]
J. Grobe, D. Le Van, J. Nientiedt, B. Krebs, M. Dartmann,
[3b]
Chem. Ber. 1988, 121, 655Ϫ664. Ϫ
J. Grobe, D. Le Van, B.
X-ray Crystallography: Data collection for 6b was performed on a
1 K-Siemens (Bruker) AXS-CCD-diffractometer using omega-scan
techniques; integration and absorption correction with Siemens-
Saint program, structure solution with direct methods and refine-
ment on F2 with Siemens SHELXTL Vers. 5.03 with riding models
for hydrogen atoms.
Krebs, R. Fröhlich, A. Schiemann, J. Organomet. Chem. 1990,
389, C29ϪC33. Ϫ [3c] J. Grobe, D. Le Van, G. Lange, Z. Natur-
forsch. B. 1993, 48, 58Ϫ67.
[4] [4a]
All quantum chemical calculations were perfomed with the
Gaussian-98 set of program systems. Gaussian 98 (Revision
A.1), M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria,
M. A. Robb, J. R. Cheeseman, V. G. Zakrezewski, J. A.
Montgomery, R. E. Stratmann, J. C. Burant, S. Dapprich, J. M.
Millam, A. D. Daniels, K. N. Kudin, M. C. Strain, O. Farkas,
J. Tomasi, V. Barone, M. Cossi, R. Cammi, B. Mennucci, C.
Pomelli, C. Adamo, S. Clifford, J. Ochterski, G. A. Petersson,
For 7b*, 10a, 11a and 12a crystallographic data (Table 2) were col-
lected with a Siemens P21 four-circle diffractometer using graphite-
monochromated Mo-Kα radiation. Semi-empirical absorption cor-
2380
Eur. J. Inorg. Chem. 1999, 2369Ϫ2381

Reactivity of Carbonyl-Functionalized Phosphaalkenes
FULL PAPER
[15] [15a]
P. Y. Ayala, Q. Cui, K. Morokuma, D. K. Malick, A. D. Rab-
uck, K. Raghavachari, J. B. Foresman, J. Cioslowski, J. V. Ortiz,
B. B. Stefanov, G. Liu, A. Liashenko, P. Piskorz, I. Komaromi,
R. Gomperts, R. L. Martin, D. J. Fox, T. Keith, M. A. Al-
Laham, C. Y. Peng, A. Nanayakkara, C. Gonzalez, M. Challac-
ombe, P. M. W. Gill, B. G. Johnson, W. Chen, M. W. Wong, J.
M. B. Power, S. G. Bott, J. L. Atwood, A. R. Barron, J.
Am. Chem. Soc. 1990, 112, 3446Ϫ3451. Ϫ [15b] M. B. Power, A.
W. Apblett, S. G. Bott, J. L. Atwood, A. R. Barron, Organomet-
[15c]
allics 1990, 9, 2529Ϫ2534. Ϫ
M. B. Power, S. G. Bott, D.
L. Clark, J. L. Atwood, A. R. Barron, Organometallics 1990,
9, 3086Ϫ3097.
[16]
[17]
L. Andres, M. Head-Gordon, E. S. Replogle, J. A. Pople, Gaus-
L. Weber, M. H. Scheffer, H.-G. Stammler, A. Stammler, Eur.
J. Inorg. Chem. 1999, 1607Ϫ1611.
[4b]
sian, Inc., Pittsburgh PA, 1998. Ϫ
A. D. Becke, Phys. Rev.
A 1988, 38, 3098Ϫ3100. A. D. Becke, J. Chem. Phys. 1993, 98,
5648Ϫ5652. A. D. Becke, J. Chem. Phys. 1996, 104, 1040Ϫ1046.
J. F. Janik, R. A. Baldwin, R. L. Wells, W. T. Pennington, G. L.
Schimek, A. L. Rheingold, L. M. Liable-Sands, Organometallics
1996, 15, 5385Ϫ5390.
Ϫ
[4c] Density Functional Methods in Chemistry (Eds.: J. K. Lab-
[18]
[19]
anowski, J. W. Andzelm), Springer Verlag, New York 1991. Ϫ
M. A. Banks, O. T. Beachley, Jr., J. D. Maloney, R. D. Rogers,
Polyhedron 1990, 9, 335Ϫ342.
[4d]
A. E. Reed, L. A. Curtiss, F. Weinhold, Chem. Rev. 1988,
[4e]
88, 899Ϫ929. Ϫ
In the optimization of all geometries Cs
For compilations of GaϪP and InϪP bond lengths see:
symmetry was imposed.
[19a] N. C. Norman, N. L. Pickett, Coord. Chem. Rev. 1995, 145,
[5]
[19b]
A. N. Chernega, A. V. Ruban, V. D. Romanenko, L. N. Markov-
ski, A. A. Korkin, M. Yu. Antipin, Y. T. Struchkov, Heteroatom
Chem. 1991, 2, 229Ϫ241 and references therein.
27Ϫ54. Ϫ
D. Wiedmann, H. ϪD. Hausen, J. Weidlein, Z.
Anorg. Allg. Chem. 1995, 621, 1351Ϫ1357. Ϫ [18c] A. H. Cowley,
R. A. Jones, Angew. Chem. 1989, 101, 1235Ϫ1243; Angew.
Chem. Int. Ed. Engl. 1989, 28, 1208.
[6] [6a]
T. C. Klebach, R. Lourens, F. Bickelhaupt, C. H. Stam, A.
[6b]
[20]
[21]
van Herk, J. Organomet. Chem. 1981, 210, 211Ϫ221. Ϫ
H.
H. Eshtiagh-Hosseini, H. W.
Lehrbuch der Anorganischen Chemie (Eds.: A. F. Holleman, E.
Wiberg), 91Ϫ100. Ed., de Gruyter Berlin 1985, p. 133.
D. C. Bradley, H. Chudzynska, M. M. Faktor, D. M. Frigo,
M. B. Hursthouse, B. Hussain, L. M.Smith, Polyhedron 1988,
7, 1289Ϫ1298.
W. Kroto, J. F. Nixon, M. J. Taylor, A. A. Frew, K. W. Muir,
[6c]
Polyhedron 1982, 1, 89Ϫ95. Ϫ
Kroto, J. F. Nixon, M. J. Maah, M. J. Taylor, J. Chem. Soc.,
[6d]
Chem. Commun. 1981, 199Ϫ200. Ϫ
R. Appel, C. Casser,
[22]
[23]
M. Immenkeppel, F. Knoch, Angew. Chem. 1984, 96, 905Ϫ906;
L. Weber, K. Reizig, R. Boese, Organometallics, 1985, 4,
2097Ϫ2101.
G. Becker, O. Mundt, M. Rössler, Z. Anorg. Allg. Chem. 1980,
468, 55Ϫ67.
C. A. Tolman, J. Am. Chem. Soc. 1970, 92, 2953Ϫ2965.
L. Weber, O. Kaminski, Synthesis 1995, 158.
H. Lehmkuhl, O. Olbrysch, H. Nehl, Liebigs Ann. Chem.
1973, 708Ϫ714.
Handbuch der präparativen anorganischen Chemie (Ed.: G.
Brauer), Vol. 3, Enke, Stuttgart 1981, p. 1827Ϫ1828.
F. W. Grevels, V. Skibbe, J. Chem. Soc., Chem. Commun. 1984,
681Ϫ683.
[6e]
Angew. Chem. Int. Ed. Engl. 1984, 23, 895. Ϫ
Casser, Tetrahedron Lett. 1984, 25, 4109Ϫ4112.
R. Appel, C.
[7] [7a]
B. Quasdorff, Dissertation, Universität Bielefeld 1997. Ϫ
[7b]
[24]
[25]
[26]
L. Weber, O. Kaminski, B. Quasdorff, H.-G. Stammler, B.
[7c]
Neumann, J. Organomet. Chem. 1997, 529, 329Ϫ341. Ϫ
L.
Weber, O. Kaminski, H.-G. Stammler, B. Neumann, V. D. Rom-
anenko, Z. Naturforsch. Teil B 1993, 48b, 1784Ϫ1794.
Ylides and Imines of Phosphorus (Ed.: A. W. Johnson), Wiley,
New York 1993.
[8]
[9]
[27]
[28]
[29]
L. Weber, S. Uthmann, H. Bögge, A. Müller, H.-G. Stammler,
B. Neumann, Organometallics 1998, 17, 3593Ϫ3598.
G. Becker, Z. Anorg. Allg. Chem. 1977, 430, 66Ϫ76.
[10]
Crystallographic data (excluding structure factors) for the struc-
tures reported in this paper have been deposited with the Cam-
bridge Crystallographic Data Centre as supplementary pub-
[11] [11a] T. Osaki, J. Otera, Y. Kawasaki, Bull. Chem. Soc. Jpn. 1973,
[11b]
46, 1803Ϫ1806. Ϫ
92, 3183Ϫ3189.
K. Issleib, E. Priebe, Chem. Ber. 1959,
lication
nos.
CCDCϪ135114
(6b),
CCDCϪ134975
[12]
[13]
J. Vicente, M. T. Chicote, I. Saura-Llamas, J. Turpin, J. Fernan-
dez-Baeza, J. Organomet. Chem. 1987, 333, 129Ϫ137.
R. O. Day, A. Willhalm, J. M. Holmes, R. R. Holmes, A.
Schmidpeter, Angew. Chem. 1985, 97, 775Ϫ777; Angew. Chem.
Int. Ed. Engl. 1985, 24, 764.
(7b*), CCDCϪ134976 (10a), CCDCϪ134977 (11a) and
CCDCϪ134978 (12a). Copies of the data can be obtained free
of charge on application to CCDC, 12 Union Road, Cambridge
CB2 1EZ, UK [Fax: (internat.) ϩ 44Ϫ1223/336Ϫ033; E-mail:
deposit@ccdc.cam.ac.uk].
[14]
S. Uthmann, L. Weber, H.-G. Stammler, A. Stammler, unpub-
lished results.
Received June 14, 1999
[I99217]
Eur. J. Inorg. Chem. 1999, 2369Ϫ2381
2381