Reactions of phosphavinyl Grignard reagents with aldehydes: Synthesis, characterisation and further reactivity of β-phosphaallylic alcohols

Article abstract of DOI:10.1039/b306607j

The reactions of the phosphavinyl Grignard reagents, Z-[RP=C(Bu ^t)MgCl(OEt₂)], R = cyclohexyl (Cy) or cyclopentyl (Cy ^P), with benzaldehyde have afforded the β-phosphaallylic alcohols, Z-RP=C(Bu^t)C(H)(OH)Ph, after quenching with methanol. This methodology has been successfully applied to a series of other alkyl, aryl and functionalised aldehydes. The β-phosphaallylic alcohol, Z-CyP=C(Bu ^t)C(H)(OH)Ph, undergoes unusual reactions with ZnEt₂, M{N(SiMe₃)₂} (M = Na or K) and Sn{N(SiMe₃) ₂}₂ to give three isomers (Z,Z-, Z,E- and E,E-) of the bis(alkenyl)diphosphine mono-oxide, PhC(H)=C(Bu^t)P(Cy)P(=O)(Cy) C(Bu^t)=C(H)Ph. By contrast its reaction with Ti(OPrⁱ) ₄ led to the formation of the secondary phosphine oxide, Z-CyP(H)(=O)C(Bu^t)=C(H)Ph. A facile synthesis of the phosphaalkenes, E-RP=C(H)Bu^t, R = Cy or mesityl (Mes), is also reported, as is an unusual tungsten complex of one of these, [{W(CO)₄[η ¹-P,η²-P=C-CyP=C(H)Bu^t]}₂]. The X-ray crystal structures of seven of the reported complexes are discussed.

Full text of DOI:10.1039/b306607j

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Reactions of phosphavinyl Grignard reagents with aldehydes:
synthesis, characterisation and further reactivity of
b-phosphaallylic alcohols
Markus Brym,a Cameron Jones,*a Mark Waugh,a Evamarie Hey-Hawkinsb and
Felecite Majoumob
a
Department of Chemistry, Cardiff University, P.O. Box 912, Park Place,
Cardiff UK CF10 3TB
Institut fu¨r Anorganische Chemie, Universita¨t Leipzig, Johannisallee 29,
D-04103, Leipzig, Germany
b
Received (in London, UK) 10th June 2003, Accepted 27th June 2003
First published as an Advance Article on the web 10th September 2003
t
=
The reactions of the phosphavinyl Grignard reagents, Z-[RP C(Bu )MgCl(OEt2)], R ¼ cyclohexyl (Cy) or
p
t
=
cyclopentyl (Cy ), with benzaldehyde have afforded the b-phosphaallylic alcohols, Z-RP C(Bu )C(H)(OH)Ph,
after quenching with methanol. This methodology has been successfully applied to a series of other alkyl, aryl
t
=
and functionalised aldehydes. The b-phosphaallylic alcohol, Z-CyP C(Bu )C(H)(OH)Ph, undergoes unusual
reactions with ZnEt2 , M{N(SiMe3)2} (M ¼ Na or K) and Sn{N(SiMe3)2}2 to give three isomers (Z,Z-,
t
Z,E- and E,E-) of the bis(alkenyl)diphosphine mono-oxide, PhC(H) C(Bu )P(Cy)P( O)(Cy)C(Bu ) C(H)Ph.
t
=
=
=
By contrast its reaction with Ti(OPri)4 led to the formation of the secondary phosphine oxide,
t
t
=
=
=
Z-CyP(H)( O)C(Bu ) C(H)Ph. A facile synthesis of the phosphaalkenes, E-RP C(H)Bu , R ¼ Cy or
mesityl (Mes), is also reported, as is an unusual tungsten complex of one of these, [{W(CO)4[Z1-P,Z2-
t
P C–CyP C(H)Bu ]}2]. The X-ray crystal structures of seven of the reported complexes are discussed.
=
=
aqueous HCl. This did not give the expected phosphaallylic
Introduction
t
=
alcohol, CyP C(Bu )C(H)(OH)Ph, but instead the saturated
(2-hydroxylalkyl)phosphine oxide, 2, which could only be
crystallised in low yield as its SRR/RSS enantiomeric pair
(Scheme 1). Compound 2 presumably forms as a result of addi-
In recent years we have been investigating the reactivity of
=
t
phosphavinyl Grignard reagents, Z-[RP C(Bu )MgCl(OEt2)]
1, R ¼ alkyl or aryl, towards main group and transition metal
halide complexes.1–8 This work has shown that phosphavinyl
Grignard reagents in some cases behave similarly to vinyl
Grignard reagents in that they form terminal phosphavinyl-
metal complexes. More often than not, however, they behave
differently in that they undergo facile metal mediated phospha-
vinyl coupling reactions to give a variety of novel heterocyclic
and/or metallo-cage compounds. We are also interested in
exploring the analogy between phosphavinyl and vinyl
Grignard reagents in organic synthesis and see 1 as being
potentially very useful synthons in this respect. A brief hint
of this potential has come from previous work by Bickelhaupt
et al. who have examined the cross-coupling of a sterically hin-
dered phosphavinyl Grignard reagent with aryl halides,9 and
=
tion of water to the P C bond of the phosphaallylic alcohol
during the quenching procedure. The spectroscopic data for
2 are consistent with its proposed structure. Its 31P{1H}
NMR spectrum displays a singlet at d 46.2 ppm which is in
the typical region for (2-hydroxylalkyl)phosphines.11 In addi-
tion its infra-red spectrum exhibits an O–H stretching band
at 3418 cmꢀ1 which is strongly suggestive of the hydroxy func-
tionality participating in hydrogen bonding.
A crystal structure analysis was carried out on 2 and the
molecular structure of its SRR isomer is depicted in Fig. 1
(see Table 1y). It should be noted that the compound crystal-
lises in the centrosymmetric space group, P21/n, and therefore
its RSS enantiomer is present in equal amounts in the same
crystal. The compound is monomeric and contains an intra-
molecular hydrogen bond between O(1) and H(19) [1.78(5)
the 1,2-addition reactions of the phosphavinyl magnesium car-
t
=
benoid, [Mes*P C(Cl)MgBr], Mes* ¼ C6H2Bu3-2,4,6, with
ꢁ
˚
acetophenone and acetyl chloride which gave the expected b-
phosphaallylic alcohol and phosphaenone products.10 Herein,
we report our efforts to extend this work to the reactions of
the less hindered Grignard reagents, 1, with mono- and dialde-
hydes. The further reactivity of generated b-phosphaallylic
alcohols towards metal alkyls, amides and alkoxides has given
a variety of unexpected results.
A, O(1)–H(19)–O(2) 151(1) ]. In addition, the P(1)–O(1) dis-
˚
tance [1.499(2) A] is in the normal range for a double bond
and all other interactions are consistent with single bonds.12
=
In order to avoid P C addition products, the reaction of 1a
with benzaldehyde was repeated and in this case quenching
with methanol led to the b-phosphaallylic alcohol, 3a, in mod-
erate yield. The generality of this reaction was tested by treat-
ing a series of alkyl, aryl and functionalised aldehydes with two
phosphavinyl Grignard reagents, 1a and 1b, Cyp ¼ cyclo-
pentyl, which in all cases afforded the expected product, 3–4,
Results and discussion
In the initial stages of this study the reaction of Z-
=
y CCDC reference numbers 212717–212723. See http://www.rsc.org/
suppdata/nj/b3/b306607j/ for crystallographic data in .cif or other
electronic format.
t
[CyP C(Bu )MgCl(OEt2)] 1a, Cy ¼ cyclohexyl, with benzal-
dehyde was carried out and the mixture quenched with
1614
New J. Chem., 2003, 27, 1614–1621
DOI: 10.1039/b306607j
This journal is # The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2003

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crystal structure analysis was carried out on one compound,
3a, to confirm its proposed structure and Z-stereochemistry
(Fig. 2, Table 1). The compound was found to crystallise with
two independent molecules in the asymmetric unit which have
essentially identical geometries and are held together with a
˚
single hydrogen bond [O(2)–H(1) 2.10(4) A, O(1)–H(1)–O(2)
165(1)ꢁ]. Of note are the P(1)–C(1) and P(2)–C(19) bond
˚
lengths (1.682 A avge.) which are normal for fully localised
double bonds.13
It was thought of interest to attempt the reactions of the
phosphaallylic alcohol, 3a, with a series of main group and
transition metal alkyls, amides and alkoxides in order to
generate metal-phosphaallylic alkoxides of the type,
=
t
[M{OC(Ph)C(Bu ) P(Cy)}n], as these could potentially exhibit
1
2
=
intramolecular Z -P and or Z -P C coordination to the
metal centre. To this end 3a was reacted with ZnEt2 ,
Sn{N(SiMe3)2}2 , Na{N(SiMe3)2} and K{N(SiMe3)2} which,
surprisingly, led to the same outcome in all cases, i.e. the high
yield formation of the bis(alkenyl)diphosphine mono-oxide
t
t
=
=
=
compound, PhC(H) C(Bu )P(Cy)P(Cy)( O)C(Bu ) C(H)Ph,
as a mixture of its Z,Z-, 5a, Z,E-, 5b, and E,E-, 5c, isomers
(Scheme 1). All three isomers are separable by fractional crys-
tallisation and have been spectroscopically and crystallo-
graphically characterised. Interestingly, their formation rates
were found to be greatly dependent on the base used. The reac-
tions involving Na{N(SiMe3)2} and K{N(SiMe3)2} were over
within 30 minutes, whilst that involving ZnEt2 was complete
after 48 hours. More sluggish still was the reaction of 3a with
Sn{N(SiMe3)2}2 which was only 50% complete after 14 days.
In an attempt to elucidate the mechanism of formation of 5,
the reaction of 3a with ZnEt2 was carefully monitored by
31P{1H} NMR spectroscopy. After 30 minutes only one singlet
at 273.1 ppm corresponding to 3a was observable. After 2
hours two new singlet resonances at 270.6 and 271.5 ppm
began to appear. After 16 hours, the resonance for 3a had dis-
appeared and after 40 hours the two new resonances had been
replaced by those for 5. It seems likely that the intermediate
Scheme 1 Reagents and conditions: i, R ¼ Cy, PhC(O)H, Et2O; ii,
HCl/H2O; iii, R0C(O)H, Et2O; iv, methanol; v, R ¼ Cy, R0 ¼ Ph,
ZnEt2 , M{N(SiMe3)2} M ¼ Na or K, Et2O; vi, R ¼ Cy, R0 ¼ Ph,
Ti(OPri)4 , Et2O.
in high yields (Scheme 1). The 31P {1H} NMR spectra of 3–4
each display low field singlet resonances in a narrow chemical
shift range (257.7–273.1 ppm) which is compatible with the
=
13
P C double bonds in these compounds. The fact that only
one resonance is seen in the spectrum of each compound con-
firms that their syntheses are stereospecific, presumably for the
Z-isomers. The infra-red spectra of 3–4 all exhibit O–H
stretching absorptions at frequencies consistent with their alco-
holic functionalities participating in hydrogen bonding. A
low field resonances are due to the originally predicted zinc
=
t
alkoxide, [Zn{OC(Ph)C(Bu ) PCy}2], which would exist as
two diastereoisomers due to the chiral carbon centre in each
alkoxide ligand. The mechanism by which this compound
converts, essentially quantitatively, to 5 is unknown but one
possibility is that it undergoes a series of rearrangement and
coupling reactions which involve the elimination of ZnO. Simi-
larly, the reactions involving the alkali metal amide starting
materials could involve elimination of M2O, but these would
have to be intermolecular processes. Insoluble powders were
obtained as by-products in all these reactions but attempts
to identify them as metal oxides by X-ray powder diffraction
failed as they gave no discernable diffraction patterns. We
know of no similar coupling reactions that involve metal oxide
elimination in organophosphorus chemistry, however rhenium
alkoxides are known to decompose to rhenium oxides with
concomitant alkyl coupling reactions.14
The 31P{1H} NMR spectra of compounds 5 display similar
AB patterns with resonances in the region of ca. d 50–60 ppm
corresponding to the P(V) centres and d 0–20 ppm for the P(III)
centre. The couplings between the two phosphorus centres are
in the normal region for one bond P–P interactions and are
=
close to those in related compounds, e.g. Ph2P( O)PPh2 .
15
All other spectroscopic data for 5 are consistent with their
structures which were confirmed by X-ray crystal structure
analyses. The molecular structures of 5a–c are depicted in Figs.
3–5 (see Table 1). All compounds are monomeric and display
P–P, C C and P O bond lengths in the normal regions.12 It is
of note that each compound contains two chiral phosphorus
centres and all crystallise as their SR/RS diastereoisomers.
In a similar reaction to those that formed 5, the alcohol,
3a, was treated with 1 equiv. of [Ti(OPri)4] in diethyl ether
and the reaction monitored by 31P{1H} NMR spectroscopy.
=
=
˚
Fig. 1 Molecular structure of compound 2. Selected bond lengths (A)
and angles (ꢁ): P(1)–O(1) 1.4992(19), P(1)–C(13) 1.814(3), P(1)–C(1)
1.832(3), P(1)–H(20) 1.36(3), O(2)–C(2) 1.438(3), C(1)–C(2) 1.559(4),
O(1)–P(1)–C(1) 111.63(12), O(1)–P(1)–C(13) 114.49(12), C(2)–C(1)–
P(1) 108.77(18).
New J. Chem., 2003, 27, 1614–1621
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Table 1 Crystal data for compounds 2, 3a, 5a-c, 6 and 9
2
3a
5a
5b
5c
6
9
Chemical formula
Fw
Crystal system
C
18H29O2P
C18H27OP
290.37
C36H52OP2
562.72
C36H52OP2
562.72
C36H52OP2
562.72
triclinic
C18H27OP
290.37
C30H42O8P2W2
960.28
308.38
monoclinic
P21/n
monoclinic
P21/n
monoclinic
P21/c
monoclinic
P21/n
monoclinic
P21/c
monoclinic
C2/c
¯
P1
Space group
˚
a (A)
˚
6.0830(12)
19.234(4)
14.925(3)
90
12.988(3)
14.268(3)
18.557(4)
90
14.908(3)
10.424(2)
20.972(4)
90
11.235(2)
14.236(3)
21.449(4)
90
10.787(2)
11.073(2)
15.414(3)
80.23(3)
69.52(3)
79.05(3)
1682.6(6)
2
6.3490(13)
14.028(3)
19.120(4)
90
25.598(5)
9.4670(19)
17.439(4)
90
b (A)
˚
c (A)
a (ꢁ)
b (ꢁ)
g (ꢁ)
100.12(3)
90
97.76(3)
90
97.64(3)
90
103.64(3)
90
95.05(3)
90
125.82(3)
90
3
˚
V (A )
1719.1(6)
4
150(2)
3407.4(12)
8
150(2)
3230.1(11)
4
150(2)
3333.8(11)
4
150(2)
1696.3(6)
4
150(2)
3426.8(12)
4
150(2)
Z
T (K)
m (Mo-Ka) (mmꢀ1
Reflections collected
Unique reflections (Rint
R 1 (I > 2s(I))
150(2)
0.154
14 339
)
0.163
16 590
0.156
23 049
0.161
26 407
0.156
28 003
0.157
29 071
6.846
27 823
)
2988 (0.1020)
0.0556
0.1249
5894 (0.1052)
0.0538
0.1134
5668 (0.1011)
0.0531
0.1085
5856 (0.0829)
0.0751
0.19
5859 (0.0656)
0.0916
0.2767
3294 (0.0975)
0.0408
0.1024
3935 (0.1137)
0.0393
0.0882
wR2 (all data)
This showed a sluggish reaction in which the signal corres-
ponding to 3a was replaced over 8 days by several signals
including two prominent singlets at d 48 and 29 ppm. Upon
work-up a moderate yield of the Z-isomer of the secondary
phosphine oxide, 6, was obtained as a crystalline solid (Scheme
1). This was subsequently shown by 31P{1H} NMR spectro-
scopy to be the compound that gave rise to the signal at d
29 ppm in the reaction mixture. The identity of the other pro-
duct could not be determined despite considerable effort. The
mechanism of formation of 6, which is an isomer of 3a, is
unknown but one possibility is that the reaction of 3a with
[Ti(OPri)4] initially leads to an intermediate titanium phos-
to be reasonably inert to P–P bond hydrolysis but this can
occur under alkaline conditions16 as in the reaction mixture
that afforded 6. To test this theory an ethereal solution of
the isomeric mixture of 5 was treated with 1 equiv. of water
in the presence of zinc hydroxide and indeed two major singlet
resonances rapidly appeared at d 48 and 29 ppm in the 31P{1H}
NMR spectrum of the reaction mixture. X-ray crystallography
confirmed the structure of 6 (Fig. 6, Table 1) which was
found to be monomeric with no extraordinary intermolecular
interactions.
In an attempt to generate bifunctional b-phosphaallylic
alcohols, the dialdehydes benzene-1,2-; -1,3- and -1,4-dicar-
boxaldehyde were reacted with 2 equiv. of 1a. No reactivity
was observed for the 1,2-dicarboxaldehyde whilst the reactions
involving the 1,3- and 1,4-dicarboxaldehydes afforded oily,
inseparable mixtures after quenching with methanol and
extraction of the products into hexane. In order to circumvent
this problem, 1b was reacted with the 1,3- and 1,4-dicarboxal-
dehydes which in the former gave the expected bis-phos-
phaallylic alcohol, 7 (Scheme 2), whilst the latter reaction
i
t
=
phaallylic alkoxide, [Ti(OPr )3{OC(Ph)C(Bu ) P(Cy)}], which
was not observed in the spectroscopic monitoring of the reac-
tion. This could then rapidly decompose to give 5, as in the
aforementioned related reactions, and the presence of adventi-
tious water could lead to hydrolysis of the P–P bond of 5 to
give 6, its corresponding E-isomer and both isomers of the
=
t
phosphinous acid, CyP(OH)C(Bu ) C(H)Ph, one of which
could have given rise to the singlet at d 48 ppm. In line with
this speculation is the fact that this signal does not exhibit a
one bond PH coupling in the corresponding proton coupled
31P NMR spectrum. Diphosphines are generally considered
Fig. 2 Molecularꢁ structure of compound 3a. Selected bond lengths
˚
(A) and angles ( ): P(1)–C(1) 1.681(2), P(2)–C(19) 1.682(3), O(1)–
Fig. 3 Molecular structure of compound 5a. Selected bond lengths
ꢁ
˚
C(2) 1.424(3), O(2)–C(20) 1.444(3), C(1)–C(2) 1.540(3), C(19)–C(20)
1.528(3), C(1)–P(1)–C(13) 108.65(11), C(19)–P(2)–C(31) 108.78(12),
C(9)–C(1)–P(1) 118.80(17), C(2)–C(1)–P(1) 125.30(18), O(1)–C(2)–
C(3) 107.74(19), O(1)–C(2)–C(1) 112.11(19), O(2)–C(20–C(19)
106.88(19), O(2)–C(20)–C(21) 112.1(2).
(A) and angles ( ): P(2)–P(1) 2.2489(10), C(1)–C(2) 1.343(3), C(19)–
(20) 1.347(3), P(1)–O(1) 1.4923(18), C(1)–P(1) 1.857(2), C(19)–P(2)
1.847(2), C(2)–C(1)–C(9) 120.4(2), C(2)–C(1)–P(1) 123.24(18), C(9)–
C(1)–P(1) 115.80(17), C(20)–C(19)–C(27) 116.6(2), C(20)–C(19)–P(2)
116.2(2), C(27)–C(19)–P(2) 127.25(17), P(2)–P(1)–O(1) 116.32(7).
1616
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Fig. 4 Molecular structure of compound 5b. Selected bond lengths
ꢁ
˚
(A) and angles ( ): P(2)–P(1) 2.2493(13), C(1)–C(2) 1.334(5), C(19)–
(20) 1.329(5), P(1)–O(1) 1.489(2), C(1)–P(1) 1.856(3), C(19)–P(2)
1.870(3), C(2)–C(1)–C(9) 120.8(3), C(2)–C(1)–P(1) 122.3(3), C(9)–
C(1)–P(1) 116.9(3), C(20)–C(19)–C(27) 128.0(3), C(20)–C(19)–P(2)
117.0(3), C(27)–C(19)–P(2) 115.0(3), P(2)–P(1)–O(1) 114.18(10).
˚
Fig. 6 Molecular structure of compound 6. Selected bond lengths (A)
and angles (ꢁ): P(1)–C(1) 1.8197(17), P(1)–O(1) 1.4865(13), C(1)–C(2)
1.339(2), C(2)–C(3) 1.481(2), C(1)–C(9) 1.541(2), C(2)–C(1)–P(1)
120.61(12), C(9)–C(1)–P(1) 116.89(12), C(2)–C(1)–C(9) 122.44(15),
O(1)–P(1)–C(1) 114.94(8).
gave an intractable mixture of products. Compound 7 was iso-
lated as colourless crystals which, unfortunately, were not of
suitable quality for X-ray analysis. Its 31P{1H} NMR spectrum
displays two singlet resonances at d 272.2 and d 272.1 ppm
which were assigned to its two diastereoisomers. These could
not be completely separated by standard methods though the
ratio of the two isomers was approximately 80 : 20 in the
recrystallised material. Attempts to react 7 with either ZnEt2
or M{N(SiMe3)2} (M ¼ Na or K) resulted in complex mix-
tures of inseparable products.
Efforts were made to extend this study by examining the
reactions of phosphavinyl Grignard reagents with a series of
other unsaturated organic substrates such as imines, esters,
carboxylic acids, isocyanides and cyanides. In all cases, how-
ever, no reactivity was observed. By contrast, the reactions
NMR spectrum exhibits a low field singlet at 257.8 ppm, whilst
a characteristic vinylic proton signal at d 8.64 ppm was
1
observed in its H NMR spectrum (2JPH ¼ 24.8 Hz). Consid-
ering the stereochemistry of 1a, it was not unexpected for 8a to
acquire E- stereochemistry upon its formation. The assignment
of this stereochemistry is supported by the size of the 2JPH cou-
pling which is in the characteristic range for E-phospha-
alkenes, according to the ‘‘cis-rule’’.17 The generality of the
reaction that yielded 8a was tested by treating the mesityl sub-
stituted phosphavinyl Grignard reagent, 1c, Mes ¼ 2,4,6-tri-
methylphenyl, with methanol which led to a high yield of the
E-phosphaalkene, 8b. This compound has been fully spectro-
scopically characterised.
Because compound 8a is an oil, attempts were made to
form a crystalline complex of it via its treatment with
[W(CO)5(THF)], though this led to a complex mixture of phos-
phorus containing products. One complex, 9 (Scheme 2), was,
however, obtained as a crystalline solid in very low yield
( < 1%). Because of this it could not be spectroscopically char-
acterised but its X-ray crystal structure was obtained, the
details of which are included here due to its novelty. The mole-
cular structure of the compound (Fig. 7, Table 1) shows it to
be dimeric with each phosphaalkene ligand coordinated to
of 1a with ketones such as acetophenone or 4-tert-butylcyclo-
=
t
hexanone yielded the phosphaalkene, E-CyP C(H)Bu , 8a.
This suggests that the basicity of 1a is too high to undergo
nucleophilic addition to the enolizable ketones. An intentional,
high yielding synthesis of compound 8a was achieved by the
direct addition of methanol to 1a (Scheme 2). Its 31P{1H}
two W(CO)4 fragments through both an Z1-P interaction,
2
0
˚
=
[P(1)–W(1 ), 2.546 (2) A] and a longer Z -P C interaction
˚
˚
[P(1)–W(1), 2.5689(16) A; C(1)–W(1), 2.457 (6) A]. As is
Fig. 5 Molecular structure of compound 5c. Selected bond lengths
ꢁ
˚
(A) and angles ( ): P(2)–P(1) 2.2459(18), C(1)–C(2) 1.332(6), C(19)–
(20) 1.334(6), P(1)–O(1) 1.499(3), C(1)–P(1) 1.853(4), C(19)–P(2)
1.878(4), C(2)–C(1)–C(9) 128.0(4), C(2)–C(1)–P(1) 115.1(3), C(9)–
C(1)–P(1) 116.9(3), C(20)–C(19)–C(27) 128.2(4), C(20)–C(19)–P(2)
117.4(3), C(27)–C(19)–P(2) 114.3(3), P(2)–P(1)-O(1) 111.00(15).
Scheme 2 Reagents and conditions: i, R ¼ Cyp, C6H4{C(O)H}2-1,3,
Et2O; ii, methanol, Et2O; iii, R ¼ Cy, W(CO)5(THF), THF.
New J. Chem., 2003, 27, 1614–1621
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t
SRR/RSS-CyP(H)( O)C(H)(Bu )C(H)(OH)Ph 2
=
A solution of benzaldehyde (0.16 ml, 1.58 mmol) in diethyl
ether (20 ml) was cooled to ꢀ78 ꢁC and a solution of 1a
(0.50 g, 1.58 mmol) in diethyl ether (5 ml) added to it over 5
mins. The resultant solution was warmed to room temperature
and stirred for 30 minutes. To this was added 1 M HCl (10 ml)
drop wise with rapid stirring. The organic layer was removed
by cannula, dried over MgSO4 , filtered and the filtrate placed
at ꢀ35 ꢁC overnight to give colourless crystals of 2 (0.05 g,
1
10%) m.p. 190–192 ꢁC; H NMR (300 MHz, C6D6 , 298 K) d
3
3
7.45 (d, JHH ¼ 7.2 Hz, 2H, Ph), 7.14 (v. tr., JHH ¼ 6.6 Hz,
3
2H, Ph), 7.05 (d, JHH ¼ 7 Hz, 1H, Ph), 6.60 (br d,
1JPH ¼ 435.7 Hz, 1H, PH), 5.46 (br d, JPH ¼ 7 Hz, 1H,
3
CH(OH)), 2.08 (br m, 1H, CH(But)PO), 1.60–0.81 (m, 11H,
Cy), 1.23 (s, 9H, CMe3); 31P NMR (121.7 MHz, C6D6 , 298
K) d 46.2 (s, P O); 13C NMR (75.6 MHz, C6D6 , 298 K) d
145.5 (s, Ph), 128.5 (s, Ph), 126.6 (s, Ph), 126.4 (s, Ph), 73.5
=
2
1
(d, JPC ¼ 3.5 Hz, PhC(OH)), 52.3 (br d, JPC ¼ 11.5 Hz,
t
1
˚
=
Fig. 7 Molecular structure of compound 9. Selected bond lengths (A)
C(Bu )P O), 36.4 (d, JPC ¼ 64.6 Hz, Cy), 33.2 (s, CMe3),
and angles (ꢁ): P(1)–C(1) 1.749(6), P(1)–W(1) 2.5689(16), C(1)–W(1)
2.457(6), P(1)–W(10) 2.546(2), C(2)–C(1)–P(1) 133.5(4), C(2)–C(1)–
W(1) 125.9(4), P(1)–C(1)–W(1) 73.1(2) W(10)–P(1)–W(1) 104.59(6).
2
29.8 (s, CMe3), 26.0 (d, JPC ¼ 8.1 Hz, Cy), 25.7 (s, Cy),
25.0 (s, Cy); MS APCI m/z 309 ([M+], 100%), 291
([M+ ꢀ H2O], 13%); IR (Nujol) n/cmꢀ1: 3418 (br s), 1644
(m), 1277 (w), 1222 (m), 1157 (m), 1112 (m), 1061 (m), 976
(w), 936 (w), 846 (w), 760 (m), 700 (m); Microanalysis found:
C 69.72, H 9.44%; calc. for C18H29O2P: C 70.10, H 9.48%.
normally the case with Z2-phosphaalkene ligation2 the P C
bond has undergone an elongation from the normal uncoordi-
=
˚
nated bond length range to 1.749(6) A, cf. the P C bond in 3a
=
˚
[1.682 A avge.]. It is also noteworthy that the coordinated
General procedure for the preparation of 3–4
phosphaalkene possesses Z-stereochemistry as opposed to
the E-stereochemistry of the free ligand. Such phosphaalkene
isomerisations upon coordination to a metal fragment are
not without precedent2 and arise from the relatively weak
A solution of the appropriate aldehyde (1.58 mmol) in diethyl
ether (20 ml) was cooled to ꢀ78 ꢁC and 1a or 1b (1.58 mmol) in
diethyl ether (10 ml) added to it over 5 mins with stirring. The
resultant solution was warmed to room temperature and stir-
red for 30 minutes after which methanol (0.20 ml, 4.74 mmol)
was added to give an immediate formation of a white preci-
pitate. The resultant suspension was filtered and volatiles
removed in vacuo from the filtrate. The oily residue was
extracted into hexane (10 ml). This was then filtered and the
solvent removed in vacuo to give an oil. In the case of 3a
and 3d the oily product was extracted into hexane (10 ml), fil-
tered and the volume lowered to ca. 3 ml in vacuo. Placement
at ꢀ35 ꢁC overnight afforded crystals of the compound.
=
nature of the p-component of the P C bond.
Conclusion
The reactions of phosphavinyl Grignard reagents toward a
variety of aldehydes have been investigated and found to lead
to the formation of a series of b- phosphaallylic alcohols. One
of these, 3a, undergoes a novel coupling and rearrangement
reaction with several metal alkyls and amides to give the
bis(alkenyl)diphosphine mono-oxide, 5, in three isomeric
forms. A facile, stereospecific synthetic route to E-phospha-
alkenes has also been described. This work has demonstrated
the potential for the use of phosphavinyl Grignard reagents in
organophosphorus synthesis, an area we continue to explore.
t
Z-CyP C(Bu )C(H)(OH)Ph 3a
=
Colourless crystals (yield 50%) m.p. 66–67 ꢁC; 1H NMR (300.5
3
MHz, C6D6 , 298 K) d 7.60 (d, JHH ¼ 8.3 Hz, 2H, Ph), 7.19
3
3
3
(dd, JHH ¼ 7.2 Hz, JHH ¼ 8.3 Hz, 2H, Ph), 7.07 (t, JHH
¼
3
7.2 Hz, 1H, Ph), 5.63 (d, JPH ¼ 5.5 Hz, 1H, CH(OH)), 2.76–
0.76 (m, 11H, Cy), 1.26 (d, JPH ¼ 2.2 Hz, 9H, CMe3); 31P
4
NMR (121.7 MHz, C6D6 , 298 K) d 273.1 (s, P C); 13C
=
Experimental details
1
NMR (75.6 MHz, C6D6 , 298 K) d 209.1 (d, JPC ¼ 55.4 Hz,
3
=
P C), 145.0 (d, JPC ¼ 3.5 Hz, Ph), 127.9 (s, Ph), 126.5 (s,
General remarks
2
Ph), 126.3 (s, Ph), 73.1 (d, JPC ¼ 11.5 Hz, PhC(H)(OH)),
2
1
All manipulations were carried out using standard Schlenk
and glove box techniques under an atmosphere of high purity
argon or dinitrogen. The solvents diethyl ether and hexane
were distilled over either potassium or Na/K alloy then
freeze/thaw degassed prior to use. 1H, 13C and 31P NMR spec-
tra were recorded on either Bruker DPX400 or Jeol Eclipse 300
spectrometers in deuterated solvents and were referenced to
the residual 1H resonances of the solvent used (1H and 13C
NMR) or to external 85% H3PO4 , 0.0 ppm (31P NMR). Mass
spectra were recorded using a VG Fisons Platform II instru-
ment under APCI conditions. Melting points were determined
in sealed glass capillaries under argon and are uncorrected.
41.8 (d, JPC ¼ 19.6 Hz, CMe3), 37.3 (d, JPC ¼ 35.8 Hz,
3
2
Cy), 31.2 (d, JPC ¼ 17.3, CMe3), 30.3 (d, JPC ¼ 15.0 Hz,
3
Cy), 26.5 (d, JPC ¼ 9.2 Hz, Cy), 26.0 (s, Cy); MS APCI
m/z 291 ([M+], 25%), 273 ([M+ ꢀ H2O], 58%); IR (Nujol)
n/cmꢀ1: 3437 (br s), 1644 (m), 1263 (m), 1217 (m), 1152 (m),
1102 (m), 1057 (m), 976 (w), 921 (w), 876 (w), 785 (w), 700
(m); Microanalysis found: C 73.50, H 9.32%; calc. for
C18H27OP: C 74.45, H 9.37%.
t
Z-CyP C(Bu )C(H)(OH)(p-PhOMe) 3b
=
1
Colourless oil (yield 79%); H NMR (300.5 MHz, C6D6 , 298
3
3
Microanalyses were obtained from the Warwick Microanalysis
=
K) d 7.48 (d, JHH ¼ 8.8 Hz, 2H, Ph), 6.78 (d, JHH ¼ 8.8
t
Service. The starting materials Z-[(Cy)P C(Bu )MgCl(OEt2)]
3
Hz, 2H, Ph), 5.67 (dd, JHH ¼ 3JPH ¼ 5.0 Hz 1H, CH(OH)),
p
t
=
=
(1a), Z-[(Cy )P C(Bu )MgCl(OEt2)] (1b) and Z-[(Mes)P C
(But)MgBr(OEt2)] (1c) were prepared by a literature proce-
dure.1 All other reagents were used as received.
3.32 (s, 3H, OCH3), 2.01–0.72 (m, 9H, Cy), 1.26 (s, 9H,
CMe3); 31P NMR (121.7 MHz, C6D6 , 298 K) d 272.7 (s,
P C); 13C NMR (75.6 MHz, C6D6 , 298 K) d 209.1 (d,
=
1618
New J. Chem., 2003, 27, 1614–1621

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1
3
=
JPC ¼ 56.5 Hz, P C), 158.8 (s, COMe), 136.4 (d, JPC ¼ 4.6
MS (EI) calc. mass for C20H29OP: 316.1956, measured mass:
316.1953.
2
Hz, Ph), 127.6 (s, Ph), 113.4 (s, Ph), 73.3 (d, JPC ¼ 11.5 Hz,
2
PhCH), 54.6 (s, PhOCH3), 41.7 (d, JPC ¼ 19.6 Hz, CMe3),
1
3
37.4 (d, JPC ¼ 35.8 Hz, Cy), 30.6 (d, JPC ¼ 16.1 Hz, Cy),
p
t
Z-Cy P C(Bu )C(H)(OH)Ph 4a
=
3
2
31.1 (d, JPC ¼ 17.3 Hz, CMe3), 26.5 (d, JPC ¼ 10.4 Hz,
Cy), 26.5 (s, Cy); MS APCI m/z 321 ([M+], 72%), 303
([M+ ꢀ H2O], 100%); IR (Nujol) n/cmꢀ1: 3478 (br s), 1609
(s), 1579 (w), 1508 (m), 1463 (s), 1358 (m), 1247 (m), 1167
(s), 1106 (w), 1037 (s), 825 (m); Accurate mass MS (EI) calc.
mass for C19H29O2P: 321.1983, measured mass: 321.1982.
1
Colourless oil (yield 76%); H NMR (300.5 MHz, C6D6 , 298
3
3
K) d 7.60 (d, JHH ¼ 7.7 Hz, 2H, Ph), 7.19 (dd, JHH ¼ 7.2
3
3
Hz, JHH ¼ 7.7 Hz, 2H, Ph), 7.07 (t, JHH ¼ 7.2 Hz, 1H,
Ph), 5.63 (dd, JPH ¼ 3JHH ¼ 5.0 Hz, 1H, CH(OH)), 2.76–
3
0.76 (m, 11H, Cyp), 1.26 (d, JPH ¼ 2.2 Hz, 9H, CMe3); 31P
4
NMR (121.7 MHz, C6D6 , 298 K) d 273.1 (s, P C); 13C
=
1
NMR (75.6 MHz, C6D6 , 298 K) d 208.7 (d, JPC ¼ 54.2 Hz,
t
Z-CyP C(Bu )C(H)(OH)Me 3c
=
3
=
P C), 144.5 (d, JPC ¼ 4.6 Hz, Ph), 127.8 (s, Ph), 127.5 (s,
1
Colourless oil (yield 86%); H NMR (300.5 MHz, C6D6 , 298
2
Ph), 126.5 (s, Ph), 73.5 (d, JPC ¼ 11.5 Hz, PhCH), 41.7 (d,
K) d 4.60 (dd, JHH ¼ 3JPH ¼ 6.6 Hz, 1H, CH(OH)), 2.01–
2JPC ¼ 19.6 Hz, CMe3), 37.7 (d, JPC ¼ 38.1 Hz, Cyp), 32.5
3
1
3
2
3
0.73 (m, 9H, Cy), 1.42 (d, JHH ¼ 6.6 Hz, 3H, C(OH)CH3),
(d, JPC ¼ 9.2 Hz, Cyp), 31.1 (d, JPC ¼ 16.2, CMe3), 26.4
1.17 (d, JPH ¼ 2.2 Hz, 9H, CMe3); 31P NMR (121.7 MHz,
(d, JPC ¼ 6.9 Hz, Cyp); MS APCI m/z 277 ([M+], 48%),
4
3
C6D6 , 298 K) d 260.9 (s, P C); 13C NMR (75.6 MHz,
259 ([M+ ꢀ H2O], 100%); IR (Nujol) n/cmꢀ1:3437 (br s),
1644 (m), 1263 (m), 1217 (m), 1152 (m), 1102 (m), 1057 (m),
976 (w), 921 (w), 876 (w), 785 (w), 700 (m).
=
1
=
C6D6 , 298 K) d 210.9 (d, JPC ¼ 56.5 Hz, P C), 70.5 (d,
2JPC ¼ 12.7 Hz, MeC(H)(OH)), 41.2 (d, JPC ¼ 19.6 Hz,
2
1
2
CMe3), 36.6 (d, JPC ¼ 35.8 Hz, Cy), 31.6 (d, JPC ¼ 10.4
Hz, Cy), 30.7 (d, 3JPC ¼ 17.3 Hz, CMe3), 26.8 (d, 3JPC ¼ 10.4
Hz, Cy), 26.1 (s, Cy), 26.0 (s, MeC(H)(OH)); MS APCI m/z
229 ([M+], 59%); IR (Nujol) n/cmꢀ1: 3307 (br s), 2322 (m),
1714 (m), 1604 (w), 1448 (s), 1363 (m), 1212 (s), 1117 (s), 951
(m), 795 (w); Accurate mass MS (EI) calc. mass for
C13H25OP: 229.1721, measured mass: 229.1720.
p
t
Z-Cy P C(Bu )C(H)(OH)(p-PhOMe) 4b
=
1
Colourless oil (yield 74%); H NMR (300.5 MHz, C6D6 , 298
3
3
K) d 7.48 (d, JHH ¼ 8.8 Hz, 2H, Ph), 6.78 (d, JHH ¼ 8.8
Hz, 2H, Ph), 5.67 (m, 1H, CH(OH)), 3.32 (s, 3H, OCH3),
2.01–0.72 (m, 9H, Cyp), 1.26 (s, 9H, CMe3); 31P NMR (121.7
MHz, C6D6 , 298 K) d 270.6 (s, P C); 13C NMR (75.6 MHz,
=
1
=
C6D6 , 298 K) d 208.7 (d, JPC ¼ 54.2 Hz, P C), 158.7 (s,
t
Z-CyP C(Bu )C(H)(OH)-trans-C(H) C(H)(p-PhOMe) 3d
=
=
3
COMe), 136.2 (d, JPC ¼ 4.6 Hz, Ph), 127.8 (s, Ph), 113.3 (s,
Yellow microcrystalline solid (yield 40%) m.p. 63–64 ꢁC; 1H
Ph), 73.4 (d, JPC ¼ 11.5 Hz, PhCH), 54.6 (s, PhOCH3), 41.7
2
3
2
1
NMR (300.5 MHz, C6D6 , 298 K) d 7.20 (d, JHH ¼ 8.8 Hz,
(d, JPC ¼ 19.6 Hz, CMe3), 37.6 (d, JPC ¼ 36.9 Hz, Cyp),
3
2
3
2H, Ph), 6.70 (d, JHH ¼ 8.8 Hz, 2H, Ph), 6.68 (dd,
32.5 (d, JPC ¼ 17.3 Hz, Cyp), 31.2 (d, JPC ¼ 17.3, CMe3),
3
4
3
JHH ¼ 16.0 Hz, JHH ¼ 1.1 Hz, 1H, CH CH), 6.35 (dd,
26.4 (d, JPC ¼ 6.9 Hz, Cyp); MS APCI m/z 307 ([M+],
=
JHH ¼ 16.0 Hz, JHH ¼ 5.0 Hz, 1H, CH CH), 5.20 (m, 1H,
28%), 289 ([M+ ꢀ H2O], 100%); IR (Nujol) n/cmꢀ1: 3487 (br
s), 1674 (m), 1604 (m), 1508 (m), 1463 (s), 1363 (m), 1252
(m), 1172 (m), 1112 (w), 1036 (w), 825 (s); Accurate mass
MS (EI) calc. mass for C18H27O2P: 307.1827, measured mass:
307.1827.
3
3
=
CH(OH)), 3.20 (s, 3H, PhOCH3), 2.03–0.73 (m, 9H, Cy),
1.28 (d, JPH ¼ 1.7 Hz, 9H, CMe3); 31P NMR (121.7 MHz,
4
C6D6 , 298 K) d 269.1 (s, P C); 13C NMR (75.6 MHz,
=
1
=
C6D6 , 298 K) d 207.1 (d, JPC ¼ 56.5 Hz, P C), 159.5 (s,
3
=
COMe), 130.7 (d, JPC ¼ 5.8 Hz, PhCH CH), 129.9 (s, Ph),
=
129.0 (s, PhCH CH), 127.6 (s, Ph), 114.2 (s, Ph), 73.9 (d,
p
Z-Cy P C(Bu )C(H)(OH)Me 4c
t
=
2JPC ¼ 12.7 Hz, C(H)(OH)), 54.5 (s, PhOCH3), 41.7 (d,
2JPC ¼ 19.6 Hz, CMe3), 37.2 (d, JPC ¼ 35.8 Hz, Cy), 31.3
1
1
Colourless oil (yield 85%); H NMR (300.5 MHz, C6D6 , 298
2
3
(d, JPC ¼ 15.0 Hz, Cy), 30.7 (d, JPC ¼ 17.3, CMe3), 26.7
K) d 4.60 (m, 1H, CH(OH)), 2.01–0.73 (m, 9H, Cyp), 1.42
3
3
(d, JPC ¼ 10.4 Hz, Cy), 26.0 (s, Cy); MS APCI m/z 347
(d, JHH ¼ 6.6 Hz, 3H, C(OH)CH3), 1.20 (s, CMe3); 31P
([M+], 50%), 329 ([M+ ꢀ H2O], 22%); IR (Nujol) n/cmꢀ1
:
NMR (121.7 MHz, C6D6 , 298 K) d 257.7 (s, P C); 13C
=
1
3407 (br s), 1604 (m), 1508 (m), 1468 (m), 1257 (s), 1172 (w),
1096 (s), 1031 (s), 795 (s); Accurate mass MS (EI) calc. mass
for C21H31O2P2 : 347.2140, measured mass: 347.2138.
NMR (75.6 MHz, C6D6 , 298 K) d 211.1 (d, JPC ¼ 55.4 Hz,
2
2
=
P C), 70.3 (d, JPC ¼ 12.7 Hz, MeCH), 41.2 (d, JPC ¼ 20.7
Hz, CMe3), 36.7 (d, 1JPC ¼ 36.9 Hz, Cyp), 33.0 (d, 2JPC ¼ 16.2
Hz, Cyp), 30.7 (d, 3JPC ¼ 17.3, CMe3), 26.5 (d, 3JPC ¼ 6.9 Hz,
3
Cyp), 26.2 (d, JPC ¼ 8.0 Hz, CH3CH); MS APCI m/z 215
t
Z-CyP C(Bu )C(H)(OH)-trans-C(H) C(H)Ph 3e
=
=
([M+], 100%), 197 ([M+ ꢀ H2O], 18%); IR (Nujol) n/cmꢀ1
:
Yellow oil (yield 76%); 1H NMR (300.5 MHz, C6D6 , 298 K) d
3337 (br s), 2353 (s), 1709 (m), 1609 (m), 1448 (m), 1363 (m),
1257 (w), 1112 (m), 800 (w).
3
3
7.28 (d, JHH ¼ 7.2 Hz, 2H, Ph), 7.09 (dd, JHH ¼ 7.7 Hz,
3JHH ¼ 7.2 Hz, 2H, Ph), 7.03 (d, JHH ¼ 7.7 Hz, 2H, Ph),
3
3
4
=
6.70 (dd, JHH ¼ 16.0 Hz, JHH ¼ 1.7 Hz, 1H, PhCH CH),
p
t
Z-Cy P C(Bu )C(H)(OH)- trans-C(H) C(H)(p-PhOMe) 4d
=
=
3
3
=
6.44 (d, JHH ¼ 16.0 Hz, JHH ¼ 5.0 Hz, 1H, CH CH), 5.20
(m, 1H, CH(OH)), 1.98–0.86 (m, 11H, Cy), 1.24 (d, 4JPH ¼ 2.2
Hz, 9H, CMe3); 31P NMR (121.7 MHz, C6D6 , 298 K) d
Yellow oil (yield 93%); 1H NMR (300.5 MHz, C6D6 , 298 K) d
3
3
7.20 (d, JHH ¼ 8.8 Hz, 2H, Ph), 6.70 (d, JHH ¼ 8.8 Hz, 2H,
270.1 (s, P C); 13C NMR (75.6 MHz, C6D6 , 298 K) d 206.7
Ph), 6.62 (d, JHH ¼ 16.0 Hz, 1H, PhCH CH), 6.38 (dd,
3
=
=
1
3
3
3
=
=
(d, JPC ¼ 56.5 Hz, P C), 137.2 (s, Ph), 132.9 (d, JPC ¼ 6.9
JHH ¼ 16.0 Hz, JHH ¼ 5.4 Hz, 1H, PhCH CH), 5.20 (dd,
3JHH ¼ 3JPH ¼ 5.0 Hz, 1H, CH(OH)), 3.20 (s, 3H, PhOCH3),
31
=
Hz, PhCH CH), 129.2 (s, PhCH CH), 128.7 (s, Ph), 127.5 (s,
=
2
4
Ph), 126.4 (s, Ph), 73.7 (d, JPC ¼ 11.5 Hz, CH(OH)C), 41.7
2.03–0.73 (m, 9H, Cyp), 1.28 (d, JPH ¼ 1.7 Hz, 9H, CMe3);
2
1
P NMR (121.7 MHz, C6D6 , 298 K) d 266.1 (s, P C); 13C
=
(d, JPC ¼ 19.6 Hz, CMe3), 37.1 (d, JPC ¼ 35.8 Hz, Cy),
2
3
1
31.3 (d, JPC ¼ 15.0 Hz, Cy), 30.7 (d, JPC ¼ 17.3, CMe3),
NMR (75.6 MHz, C6D6 , 298 K) d 207.2 (d, JPC ¼ 54.2 Hz,
3
3
=
=
26.6 (d, JPC ¼ 9.2 Hz, Cy), 26.0 (s, Cy); MS APCI m/z 317
P C), 159.5 (s, COMe), 131.5 (d, JPC ¼ 5.8 Hz, PhCH CH),
([M+], 100%), 299 ([M+ ꢀ H2O], 21%); IR (Nujol) n/cmꢀ1
3397 (br s), 1714 (m), 1699 (m), 1599 (m), 1494 (s), 1448 (s),
1388 (m), 1358 (s), 1257 (s), 1232 (m), 1092 (s), 1027 (s), 966
(m), 881 (w), 845 (w), 801 (m), 755 (m), 695 (s); Accurate mass
=
130.0 (s, Ph), 129.2 (s, PhCH CH), 127.6 (s, Ph), 114.2 (s, Ph),
74.0 (d, 2JPC ¼ 11.5 Hz, CH(OH)), 54.5 (s, PhOCH3), 41.6 (d,
2JPC ¼ 19.6 Hz, CMe3), 37.4 (d, 1JPC ¼ 36.9 Hz, Cyp), 32.8 (d,
2JPC ¼ 18.4 Hz, Cyp), 30.8 (d, JPC ¼ 16.2, CMe3), 26.6
3
New J. Chem., 2003, 27, 1614–1621
1619

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(d, 3JPC ¼ 6.9 Hz, Cyp); MS APCI m/z 333 ([M+], 100%), 315
([M+ ꢀ H2O], 38%); IR (Nujol) n/cmꢀ1: 3407 (br s), 1604 (m),
1508 (m), 1468 (m), 1257 (s), 1172 (w), 1096 (s), 1031 (s), 795
(s); Accurate mass MS (EI) calc. mass for C20H29O2P:
332.1902, measured mass: 332.1902.
overnight to give colourless crystals of 5b. (0.11 g, 31%) m.p.
188–190 ꢁC, 1H NMR (300.5 MHz, C6D6 , 298 K) d 7.97–
=
6.96 (m, 12H, Ph and C CH), 2.53–0.87 (m, 22H, Cy), 1.63
(s, 9H, CMe3), 1.33 (s, 9H, CMe3); 31P NMR (121.7 MHz,
1
=
C6D6 , 298 K) d 55.4 (d, JPP ¼ 287.2 Hz, PP O), ꢀ12.7 (d,
1
+
=
JPP ¼ 287.2 Hz, PP O); MS APCI m/z 563 ([M ], 100%);
IR (Nujol) n/cmꢀ1: 1298 (m), 1263 (m), 1228 (m), 1177 (m),
1142 (s), 1077 (m), 1042 (m), 997 (m), 921 (w), 886 (w), 856
(w), 745 (s); Accurate mass MS (CI) calc. mass for
C36H52OP2 : 563.3566, [M + H], measured mass: 563.3581.
p
Z-Cy P C(Bu )C(H)(OH)-trans-C(H) C(H)Ph 4e
t
=
=
Yellow oil (yield 79%); 1H NMR (300.5 MHz, C6D6 , 298 K) d
7.70 (d, 3JHH ¼ 7.2 Hz, 2H, Ph), 7.10 (dd, 3JHH ¼ 3JHH ¼ 7.2
3
Hz, 2H, Ph), 7.03 (t, JHH ¼ 7.2 Hz, 1H, Ph), 6.63 (dd,
3
3
4
=
JHH ¼ 16.0 Hz, JHH ¼ 1.1 Hz, 1H, PhCH CH), 6.34 (dd,
t
E,E-PhC(H) C(Bu )P(Cy)P(Cy)( O)C(Bu ) C(H)Ph 5c
t
3
=
=
=
=
JHH ¼ 16.0 Hz, JHH ¼ 4.4 Hz, 1H, PhCH CH), 5.20 (m,
1H, CH(OH)), 2.03–0.83 (m, 9H, Cyp), 1.25 (d, JPH ¼ 2.2
4
To a suspension of K{N(SiMe3)2} (0.26 g, 1.31 mmol) in
diethyl ether (20 ml) at ꢀ78 ꢁC was added 3a (0.38 g, 1.31
mmol) in diethyl ether (20 ml). The resultant solution was
warmed to room temperature and stirred for 16 hours. It
was then filtered and the volatiles removed from the filtrate
in vacuo to leave an oily residue which was extracted into hex-
ane (10 ml). The extract was concentrated in vacuo to ca. 3 ml
and placed at ꢀ35 ꢁC overnight to give colourless crystals of
5c. (0.11 g, 31%) m.p. 190–192 ꢁC; 1H NMR (300.5 MHz,
Hz, 9H, CMe3); 31P NMR (121.7 MHz, C6D6 , 298 K) d
267.6 (s, P C) 13C NMR (75.6 MHz, C6D6 , 298 K) d 206.6
=
1
3
=
(d, JPC ¼ 54.2 Hz, P C), 137.2 (s, Ph), 132.9 (d, JPC ¼ 5.8
=
Hz, PhCH CH), 129.8 (s, PhCH CH), 128.7 (s, Ph), 127.5
=
2
(s, Ph), 126.5 (s, Ph), 73.9 (d, JPC ¼ 11.5 Hz, CH(OH)),
2
1
41.6 (d, JPC ¼ 19.6 Hz, CMe3), 37.4 (d, JPC ¼ 36.9 Hz,
Cyp), 32.4 (d, JPC ¼ 18.5 Hz, Cyp), 30.7 (d, JPC ¼ 17.3,
2
3
CMe3), 26.6 (d, JPC ¼ 11.5 Hz, Cyp); MS APCI m/z 303
3
([M+], 100%); IR (Nujol) n/cmꢀ1: 3398 (br s), 1720 (m),
1674 (m), 1594 (m), 1573 (m), 1489 (s), 1388 (m), 1363 (s),
1262 (m), 1232 (w), 1157 (w), 1097 (s), 1032 (s), 966 (m), 896
(w), 801 (m), 750 (m), 690 (s); Accurate mass MS (ES+) calc.
mass for C19H27OP: 303.1872 [M + H], measured mass:
303.1870
=
C6D6 , 298 K) d 8.20–7.01 (m, 12H, Ph and C CH), 2.43–
0.63 (m, 22H, Cy), 1.65 (s, 9H, CMe3), 1.63 (s, 9H, CMe3);
1
31P NMR (121.7 MHz, C6D6 , 298 K) d 50.1 (d, JPP ¼ 332.1
1
Hz, PP O), 0.0 (d, JPP ¼ 332.1 Hz, PP O); 13C NMR (75.6
=
=
1
2
MHz, C6D6 , 298 K) d 148.9 (dd, JPC ¼ 41.5 Hz, JPC ¼ 6.9
2
3
=
Hz, P(O)C C), 147.8 (dd, JPC ¼ 38.1 Hz, JPC ¼ 11.5 Hz,
1
2
=
P(O)C C), 146.4 (dd, JPC ¼ 45.0 Hz, JPC ¼ 3.5 Hz,
t
Z,Z-PhC(H) C(Bu )P(Cy)P(Cy)( O)C(Bu ) C(H)Ph 5a
t
3
=
=
=
=
P(O)PC C), 139.4 (d, JPC ¼ 13.9 Hz, Ph), 138.0 (d,
3
3
=
JPC ¼ 5.8 Hz, Ph), 136.6 (d, JPC ¼ 6.9 Hz, P(O)PC C),
To a suspension of Na{N(SiMe3)2} (0.24 g, 1.31 mmol) in
diethyl ether (20 ml) at ꢀ78 ꢁC was added 3a (0.38 g, 1.31
mmol) in diethyl ether (20 ml). The resultant solution was
warmed to room temperature and stirred for 16 hours. It
was then filtered and the volatiles removed from the filtrate
in vacuo to leave an oily residue which was extracted into hex-
ane (10 ml). The extract was concentrated in vacuo to ca. 3 ml
and placed at ꢀ35 ꢁC overnight to give colourless crystals of
5a. (0.09 g, 25%) m.p. 218–220 ꢁC; 1H NMR (300.5 MHz,
130.5 (s, Ph), 129.0 (s, Ph), 128.7 (s, Ph), 128.6 (s, Ph), 127.1
1
2
(s, Ph), 126.6 (s, Ph), 42.2 (dd, JPC ¼ 51.2 Hz, JPC ¼ 19.6
2
2
Hz, Cy), 41.1 (d, JPC ¼ 6.9 Hz, CMe3), 40.1 (d, JPC ¼ 8.1,
1
2
CMe3), 34.5 (dd, JPC ¼ 43.1 Hz, JPC ¼ 4.6 Hz, Cy), 33.6
2
(d, JPC ¼ 13.1 Hz, Cy), 32.5 (s, CMe3), 31.1 (s, CMe3), 27.0
(s, Cy), 26.7 (s, Cy), 26.1 (s, Cy), 25.9 (s, Cy), 25.3 (s, Cy);
MS APCI m/z 563 ([M+], 100%); IR (Nujol) n/cmꢀ1: 1298
(m), 1263 (m), 1228 (m), 1177 (m), 1142 (s), 1077 (m), 1042
(m), 997 (m), 921 (w), 886 (w), 856 (w), 745 (s); Accurate mass
MS (CI) calc. mass for C36H52OP2 : 563.3566, [M + H], mea-
sured mass: 563.3576.
=
C6D6 , 298 K) d 8.28–7.00 (m, 12H, Ph and C CH), 2.50–
0.85 (m, 22H, Cy), 1.47 (s, 9H, CMe3), 1.21 (s, 9H, CMe3);
1
31P NMR (121.7 MHz, C6D6 , 298 K) d 62.2 (d, JPP ¼ 251.3
1
Hz, PP O), ꢀ20.6 (d, JPP ¼ 251.3 Hz, PP O); 13C NMR
=
=
1
(75.6 MHz, C6D6 , 298 K) d 148.9 (dd, JPC ¼ 46.7 Hz,
t
Z-PhC(H) C(Bu )P(O)(H)Cy 6
=
2
3
2
2
=
JPC ¼ 6.9 Hz, P(O)C CH), 147.8 (dd, JPC ¼ 38.1 Hz,
1
JPC ¼ 12.2 Hz, P(O)C CH), 146.3 (dd, JPC ¼ 45.0 Hz,
To a solution of Ti(OPri)4 (0.09 ml, 1.27 mmol) in diethyl ether
(20 ml) at ꢀ78 ꢁC was added 3a (0.37 g, 1.27 mmol) in diethyl
ether (20 ml). The resultant solution was warmed to room tem-
perature and stirred for eight days. It was then filtered and the
volatiles removed from the filtrate in vacuo to leave an oily resi-
due which was extracted into hexane (15 ml). The extract was
concentrated in vacuo to ca. 5 ml and placed at ꢀ35 ꢁC over-
night to give colourless crystals of 6. (0.11 g, 31%) m.p. 91–
=
3
=
JPC ¼ 3.5 Hz, P(O)PC CH), 139.4 (d, JPC ¼ 13.8 Hz, Ph),
3
4
138.0 (d, JPC ¼ 4.6 Hz, Ph), 136.6 (d, JPC ¼ 8.1 Hz,
=
P(O)PC CH), 130.3 (s, Ph), 128.7 (s, Ph), 128.6 (s, Ph),
127.2 (s, Ph), 127.1 (s, Ph), 126.6 (s, Ph), 42.1 (dd, 1JPC ¼ 61.2
2
2
Hz, JPC ¼ 19.6 Hz, Cy), 41.0 (d, JPC ¼ 6.9 Hz, CMe3), 40.1
2
1
2
(d, JPC ¼ 8.1, CMe3), 34.5 (dd, JPC ¼ 26.5 Hz, JPC ¼ 4.6
Hz, Cy), 33.6 (s, Cy), 32.5 (s, CMe3), 31.1 (s, CMe3), 27.0 (s,
Cy), 26.5 (s, Cy), 26.1 (s, Cy), 25.9 (s, Cy), 25.3 (s, Cy); MS
APCI m/z 563 ([M+], 12%); IR (Nujol) n/cmꢀ1: 1298 (m),
1263 (m), 1228 (m), 1177 (m), 1142 (s), 1077 (m), 1042 (m),
997 (m), 921 (w), 886 (w), 856 (w), 745 (s); Accurate mass
MS (EI) calc. mass for C36H52OP2 : 562.3493, measured mass:
562.3493.
93 ꢁC, 1H NMR (300.5 MHz, C6D6 , 298 K) d 7.52 (d,
3
=
JHH ¼ 7.7 Hz, 2H, Ph), 7.11 (br, s, 1H, PhCH C), 7.08
3
3
(dd, JHH ¼ 7.7 Hz, 2H, Ph), 7.02 (t, JHH ¼ 7.2 Hz, 1H,
1
3
4
Ph), 6.93 (ddd, JPH ¼ 441.7 Hz, JPH ¼ 7.2 Hz, JPH ¼ 2.2
Hz, 1H, PH), 2.30–0.66 (m, 11H, Cy), 1.26 (s, 9H, CMe3);
=
31
P NMR (121.7 MHz, C6D6 , 298 K) d 28.6 (s, P O); 13C
1
NMR (75.6 MHz, C6D6 , 298 K) d 145.0 (d, JPC ¼ 76.2 Hz,
2
=
=
PC CPh), 138.9 (d, JPC ¼ 8.1 Hz, PC CPh), 137.3 (d,
t
Z,E-PhC(H) C(Bu )P(Cy)P(Cy)( O)C(Bu ) C(H)Ph 5b
t
=
=
=
3JPC ¼ 8.1 Hz, Ph), 129.2 (s, Ph), 128.0 (s, Ph), 127.7 (s, Ph),
2
1
To a THF (20 ml) solution of 1 M ZnEt2 (0.66 ml, 0.66 mmol)
at ꢀ78 ꢁC was added 3a (0.38 g, 1.31 mmol) dissolved in
THF (20 ml). The resultant solution was warmed to room
temperature and stirred for 2 days. It was then filtered and
the volatiles removed from the filtrate in vacuo to leave an oily
residue which was extracted into hexane (10 ml). The extract
was concentrated in vacuo to ca. 3 ml and placed at ꢀ35 ꢁC
37.0 (d, JPC ¼ 9.2 Hz, CMe3), 36.4 (d, JPC ¼ 68.1 Hz, Cy),
3
30.1 (d, JPC ¼ 3.5, CMe3), 26.7 (s, Cy), 26.1 (s, Cy), 25.6 (s,
Cy); MS APCI m/z 291 ([M+], 29%); IR (Nujol) n/cmꢀ1
:
2332 (m), 1599 (m), 1268 (m), 1212 (m), 1157 (s), 1117 (s),
1012 (s), 941 (w), 921 (w), 876 (w), 750 (m), 705 (w); Accurate
mass MS (ES+) calc. mass for C18H27OP: 291.1872 [M + H],
measured mass: 291.1873.
1620
New J. Chem., 2003, 27, 1614–1621

View Article Online
t
C6H4{C(H)(OH)C(Bu ) PCy }2-1,3 7
p
=
Structure determinations
To a solution of benzene-1,3-dicarboxaldehyde (0.11 g, 0.83
mmol) in diethyl ether (20 ml) at ꢀ78 ꢁC was added 1b (0.50
g, 1.65 mmol) in diethyl ether (20 ml). The resultant solution
was warmed to room temperature and stirred for 30 minutes.
Methanol (0.20 ml, 4.74 mmol) was then added with the
immediate formation of a white precipitate. The suspension
was filtered and volatiles were removed in vacuo. The oily resi-
due was extracted into hexane (10 ml), filtered and the solvent
removed in vacuo from the filtrate to give a colourless oil. This
was extracted into hexane (10 ml) and concentrated to ca. 3 ml
in vacuo. Placement at ꢀ35 ꢁC overnight gave colourless crys-
tals of 7 (0.06 g, 15%) m.p. 122–124 ꢁC; Data for major isomer
Crystals of 2, 3a, 5a–c, 6 and 9 suitable for X-ray structure
determination were mounted in silicone oil or epoxy resin.
Crystallographic measurements were made using a Nonius
Kappa CCD diffractometer. The structures were solved by
direct methods and refined on F2 by full matrix least squares
(SHELX97)18 using all unique data. All non-hydrogen atoms
are anisotropic with H-atoms either included in calculated
positions (riding model) or their positions and thermal para-
meters refined isotropically. The relatively high r-factor for
the structure of 5c was due to the poor quality of the sample
used in the experiment. Despite this, the molecular connectiv-
ity shown for this compound in Fig. 5 is unambiguous. Crystal
data, details of data collections and refinements are given in
Table 1. The molecular structures of the complexes are
depicted in Figs. 1–7 and show ellipsoids at the 30% probabil-
ity level.
1
only: H NMR (300.5 MHz, C6D6 , 298 K) d 7.74 (s, 1H, Ph),
3
3
7.56 (d, JHH ¼ 7.7 Hz, 2H, Ph), 7.23 (t, JHH ¼ 7.7 Hz, 1H,
ArH), 5.64 (dd, JPH ¼ 3JHH ¼ 5.0 Hz, 2H, C(OH)H), 3.03–
3
0.85 (m, 22H, Cy), 1.27 (s, 18H, CMe3); 31P NMR (121.7
MHz, C6D6 , 298 K) d 272.1 (s, P C); 13C NMR (75.6 MHz,
=
1
=
C6D6 , 298 K) d 208.9 (d, JPC ¼ 54.2 Hz, P C), 144.2 (d,
3JPC ¼ 4.6 Hz, Ar), 128.5 (s, Ar), 125.1 (s, Ar), 124.6 (s, Ar),
Acknowledgements
2
2
73.6 (d, JPC ¼ 11.5 Hz, CH(OH)), 41.8 (d, JPC ¼ 19.6 Hz,
1
2
We gratefully acknowledge financial support from the EPSRC
(studentship for MB and postdoctoral fellowship for MW) and
the DAAD (travel grant for FM). Thanks also go to the
EPSRC Mass Spectrometry Service, Swansea, UK for the
accurate mass determinations.
CMe3), 37.7 (d, JPC ¼ 38.1 Hz, Cy), 31.5 (d, JPC ¼ 18.5
Hz, Cy), 31.1 (s, CMe3), 26.4 (s, Cy); MS APCI m/z 473
([M+ ꢀ H], 95%); IR (Nujol) n/cmꢀ1: 3447 (br s), 1700 (m),
1594 (m), 1282 (m), 1216 (m), 1155 (m), 1115 (m), 1048 (s),
961 (w), 900 (w), 802 (m), 720 (m).
t
E-CyP C(H)Bu 8a
=
References
To a solution of 1a (0.50 g, 1.58 mmol) in diethyl ether (20 ml)
at 25 ꢁC was added methanol (0.20 ml, 4.74 mmol) to give the
immediate formation of a white precipitate. The suspension
was filtered and volatiles were removed in vacuo from the fil-
trate to yield an oily residue which was extracted into hexane
(10 ml). The resultant suspension was then filtered and vola-
tiles removed from the filtrate in vacuo. This gave 8a as a col-
1
2
3
4
5
6
7
8
9
D. E. Hibbs, C. Jones and A. F. Richards, J. Chem. Soc., Dalton
Trans., 1999, 3531.
C. Jones and A. F. Richards, J. Chem Soc., Dalton Trans., 2000,
3233.
C. Jones and A. F. Richards, J. Organomet. Chem., 2001,
629, 109.
C. Jones, P. C. Junk, A. F. Richards and M. Waugh, New
J. Chem., 2002, 26, 1209.
C. Jones, J. A. Platts and A. F. Richards, Chem. Commun.,
2001, 663.
C. Jones, A. F. Richards, S. Fritzsche and E. Hey-Hawkins,
Organometallics, 2002, 21, 438.
M. Brym, C. Jones and A. F. Richards, J. Chem. Soc., Dalton
Trans., 2002, 2800.
S. Aldridge, C. Jones, P. C. Junk, A. F. Richards and M. Waugh,
J. Organomet. Chem., 2003, 665, 127.
ourless oil (0.28 g, 96%), 1H NMR (300.5 MHz, C6D6 , 298 K)
2
=
d 8.64 (d, JPH ¼ 24.8 Hz, 1H, P CH), 2.10–1.10 (m, 11H,
Cy), 1.15 (d, JPH ¼ 1.7 Hz, 9H, CMe3); 31P NMR (121.7
4
MHz, C6D6 , 298 K) d 257.8 (s, P C); 13C NMR (75.6 MHz,
=
1
=
C6D6 , 298 K) d 198.2 (d, JPC ¼ 44.8 Hz, P C), 41.1 (d,
1JPC ¼ 33.2 Hz, Cy), 36.1 (d, JPC ¼ 11.9 Hz, CMe3), 32.3
2
2
3
(d, JPC ¼ 9.1 Hz, Cy), 30.8 (s, CMe3), 30.5 (d, JPC ¼ 12.2
Hz, Cy), 26.0 (s, Cy); MS APCI m/z 185 ([M+], 25%); IR
(Nujol) n/cmꢀ1: 1448 (s), 1358 (m), 1258 (m), 1167 (m), 1117
(m), 1017 (m), 936 (w), 886 (w), 846 (w), 801 (w).
M. van der Sluis, V. Beverwijk, A. Termaten, E. Gavrilova, F.
Bickelhaupt, H. Kooijman, N. Veldman and A. L. Spek, Organo-
metallics, 1997, 16, 1144.
10 M. van der Sluis, J. B. M. Wit and F. Bickelhaupt, Organo-
metallics, 1996, 15, 174.
11 D. G. Genov, R. A. Kresinski and J. C. Tebby, J. Org. Chem.,
1998, 63, 2574.
t
E-MesP C(H)Bu 8b
=
A similar procedure to the preparation of 8a was employed.
Colourless oil (yield 88%), H NMR (300.5 MHz, C6D6 , 298
12 As determined from a survey of the Cambridge Crystallographic
Database.
13 L. Weber, Angew. Chem., Int. Ed. Engl., 1996, 35, 271 and refer-
ences therein.
1
2
=
K) d 8.43 (d, JPH ¼ 25.3 Hz, 1H, P CH), 7.15 (s, 2H,
4
ArH), 2.31 (s, 6H, Me), 2.13 (s, 3H, Me), 1.15 (d, JPH ¼ 2.2
14 P. G. Edwards, G. Wilkinson, M. B. Hursthouse and K. M. A.
Malik, J. Chem. Soc., Dalton Trans., 1980, 2467.
15 D. J. Irvine, C. Glidewell, D. J. Cole-Hamilton, J. C. Barnes and
A. Howie, J. Chem. Soc., Dalton Trans., 1991, 1765.
16 A. H. Cowley, Chem. Rev., 1965, 65, 617 and references therein.
17 (a) V. D. Romaneko, A. V. Ruban, A. N. Chernega, M. I.
Pevolotskii, M. Yu. Antipin, Yu. T. Struchkov and L. N.
Markovskii, Zh. Obshch. Khim., 1989, 59, 1718; (b) S. J. Geode
and F. Bickelhaupt, Chem. Ber., 1991, 124, 2677.
18 G. M. Sheldrick, SHELXL-97, Program for refinement of crystal
structures, University of Go¨ttingen, Germany, 1997.
Hz, 9H, CMe3); 31P NMR (121.7 MHz, C6D6 , 298 K) d
228.4 (s, P C); 13C NMR (75.6 MHz, C6D6 , 298 K) d 203.3
=
1
1
=
(d, JPC ¼ 43.8 Hz, P C), 186.7 (d, JPC ¼ 51.9 Hz, Ar),
2
140.0 (d, JPC ¼ 5.8 Hz, Ar), 137.6 (s, Ar), 128.7 (s, Ar),
2
3
38.9 (d, JPC ¼ 13.8 Hz, CMe3), 30.1 (d, JPC ¼ 10.8 Hz,
3
CMe3), 23.0 (d, JPC ¼ 9.2 Hz, Me), 20.9 (s, Me); MS APCI
m/z 221 ([M+], 17%), 151 ([M+ ꢀ CHBut], 100%); IR (Nujol)
n/cmꢀ1: 1604 (m), 1458 (s), 1358 (m), 1258 (m), 1102 (m),
1031 (m), 871 (w), 845 (w), 806 (w).
New J. Chem., 2003, 27, 1614–1621
1621