Synthesis and characterization of tungsten alkenyl-carbyne complexes [(dppe)(CO)2LW≡CCH=CCH2(CH2) nCH2CH2][BF4] (L = CO, MeCN, PMe3) and [(dppe)(CO)2XW≡CCH=CCH2(CH2]

Article abstract of DOI:10.1021/om9601460

Alkenyl-vinylidene complexes mer-[(dppe)(CO)₃W=C=CHC=CH(CH₂)_nCH ₂CH₂] (dppe = 1,2-bis(diphenylphosphino)ethane; n = 1 (1a), n = 3 (1c), n = 4 (1d)) have been prepared by reaction of the complex fac-[(dppe)(CO)₃W(Me₂CO)] with 1-ethynylcyclopentanol, 1-ethynylcycloheptanol, and 1-ethynylcyclooctanol. Protonation at the C_δ of the alkenyl-vinylidene moiety with HBF₄·OEt₂ in diethyl ether or THF leads to the formation of cationic alkenyl-carbyne complexes mer-[(dppe)(CO)₃W=CCH=CCH₂(CH₂) _nCH₂CH₂][BF₄] (n = 1 (2a), n = 3 (2c), n = 4 (2d)). When the protonation is carried out in CH₂Cl₂, isomeric carbyne complexes mer-[(dppe)(CO)₃W≡CCH₂C=CH(CH₂) _nCH₂CH₂][BF₄] (2a′, 2c′, 2d′) are also generated. The alkenyl-carbyne complexes undergo carbonyl substitution by donor ligands to give dicarbonyl derivatives of the following types: (a) cationic complexes trans-[(dppe)(CO)₂LW≡ CCH=CCH₂(CH₂)_nCH₂CH ₂][BF₄] (L = CH₃CN, n = 1 (3a), n = 4 (3d); L = PMe₃, n = 1 (4a), n = 4 (4d)) and (b) neutral complexes trans-[(dppe)(CO)₂XW≡CCH=CCH₂(CH₂) _nCH₂CH₂] (X = Cl, n = 1 (5a), n = 2 (5b), n = 3 (5c), n = 4 (5d); X = Br, n = 1 (6a), n = 4 (6d); X = I, n = 1 (7a), n = 3 (7c), n = 4 (7d)). The structure of complex 5a was determined by X-ray diffraction methods. The W atom displays a distorted octahedral coordination with the Cl atom [W-Cl = 2.540(1) A?] trans to the alkenyl-carbyne group [W≡C = 1.830(3) A?]. IR and ¹H, ³¹P, ¹³C, and ¹⁸³W NMR data are reported. The sequence for the trans influence in the order alkenyl-carbyne > alkenyl-vinylidene > CO could be found from the corresponding ¹J(³¹P-¹⁸³W) values. The low values for the alkenyl-carbyne groups are among the lowest ever reported, indicating a high trans influence of the carbyne group. ¹⁸³W chemical shifts of compounds 1a-7a were obtained through two-dimensional indirect ³¹P, ¹⁸³W recording techniques. A down field shifting of ¹⁸³W resonances with decreasing π-acceptor ability of the ligands in complexes 2a-7a was observed.

Full text of DOI:10.1021/om9601460

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4274
Organometallics 1996, 15, 4274-4284
Syn th esis a n d Ch a r a cter iza tion of Tu n gsten
Alk en yl-Ca r byn e Com p lexes
[(d p p e)(CO)2LWtCCHdCCH2(CH2)n CH2CH2][BF 4] (L )
CO, MeCN, P Me3) a n d
[(d p p e)(CO)2XWtCCHdCCH2(CH2)n CH2CH2] (X ) Cl, Br ,
I). X-r a y Cr ysta l Str u ctu r e of
[(d p p e)(CO)2ClWtCCHdCCH2CH2CH2CH2] a n d 183W NMR
Stu d ies
Lei Zhang, M. Pilar Gamasa, J ose´ Gimeno,* Rodrigo J . Carbajo, and
Fernando Lo´pez-Ortiz
Instituto Universitario de Quı´mica Organometa´lica “Enrique Moles” (Unidad Asociada al
CSIC), Departamento de Quı´mica Orga´nica e Inorga´nica, Facultad de Quı´mica, Universidad
de Oviedo, E-33071 Oviedo, Spain
Maurizio Lanfranchi and Antonio Tiripicchio
Dipartimento di Chimica Generale ed Inorganica, Chimica Analitica, Chimica Fisica,
Universita` di Parma, Centro di Studio per la Strutturistica Diffrattometrica del CNR,
I-43100 Parma, Italy
Received February 28, 1996X
Alkenyl-vinylidene complexes mer-[(dppe)(CO)3WdCdCHCdCH(CH2)nCH2CH2] (dppe )
1,2-bis(diphenylphosphino)ethane; n ) 1 (1a ), n ) 3 (1c), n ) 4 (1d )) have been prepared by
reaction of the complex fac-[(dppe)(CO)3W(Me2CO)] with 1-ethynylcyclopentanol, 1-ethynyl-
cycloheptanol, and 1-ethynylcyclooctanol. Protonation at the Cδ of the alkenyl-vinylidene
moiety with HBF4‚OEt2 in diethyl ether or THF leads to the formation of cationic alkenyl-
carbyne complexes mer-[(dppe)(CO)3WtCCHdCCH2(CH2)nCH2CH2][BF4] (n ) 1 (2a ), n ) 3
(2c), n ) 4 (2d )). When the protonation is carried out in CH2Cl2, isomeric carbyne complexes
mer-[(dppe)(CO)3WtCCH2CdCH(CH2)nCH2CH2][BF4] (2a ′, 2c′, 2d ′) are also generated. The
alkenyl-carbyne complexes undergo carbonyl substitution by donor ligands to give dicarbonyl
derivatives of the following types: (a) cationic complexes trans-[(dppe)(CO)2LWt
CCHdCCH2(CH2)nCH2CH2][BF4] (L ) CH3CN, n ) 1 (3a ), n ) 4 (3d ); L ) PMe3, n ) 1 (4a ),
n ) 4 (4d )) and (b) neutral complexes trans-[(dppe)(CO)2XWtCCHdCCH2(CH2)nCH2CH2]
(X ) Cl, n ) 1 (5a ), n ) 2 (5b), n ) 3 (5c), n ) 4 (5d ); X ) Br, n ) 1 (6a ), n ) 4 (6d ); X )
I, n ) 1 (7a ), n ) 3 (7c), n ) 4 (7d )). The structure of complex 5a was determined by X-ray
diffraction methods. The W atom displays a distorted octahedral coordination with the Cl
atom [WsCl ) 2.540(1) Å] trans to the alkenyl-carbyne group [WtC ) 1.830(3) Å]. IR
1
and H, 31P, 13C, and 183W NMR data are reported. The sequence for the trans influence in
the order alkenyl-carbyne > alkenyl-vinylidene > CO could be found from the corresponding
1J (31P-183W) values. The low values for the alkenyl-carbyne groups are among the lowest
ever reported, indicating a high trans influence of the carbyne group. 183W chemical shifts
of compounds 1a -7a were obtained through two-dimensional indirect 31P, 183W recording
techniques. A down field shifting of 183W resonances with decreasing π-acceptor ability of
the ligands in complexes 2a -7a was observed.
In tr od u ction
Transition metal carbene complexes, and particularly
Fischer type unsaturated carbene complexes, have been
extensively used in organic synthesis due to the wide
range of synthetic applications.1,2 In contrast, the utility
of carbyne metal complexes for similar purposes is
comparatively much less exploited. Although the chem-
istry of metal-carbon triple bonds has been explored
(1) See for instance: (a) Do¨tz, K. H. Angew. Chem., Int. Ed. Engl.
1984, 23, 587. (b) Do¨tz, K. H. In Organometallics in Organic Synthe-
sis: Aspects of a Modern Interdisciplinary Field; tom Dieck, H., de
Meijere, A., Eds.; Springer: Berlin, 1988. (c) Wulff, W. D. In Advances
in Metal-Organic Chemistry; Liebeskind, L. S., Ed.; J AI Press Inc.:
Greenwich, CT, 1989; Vol. 1. (d) Wulff, W. D. In Comprehensive Organic
Synthesis; Trost, B. M., Fleming, I., Eds.; Pergamon Press: Elmsford,
NY, 1991; Vol. 5.
X Abstract published in Advance ACS Abstracts, August 1, 1996.
S0276-7333(96)00146-X CCC: $12 00 © 1996 American Chemical Society

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Tungsten Alkenyl-Carbyne Complexes
Organometallics, Vol. 15, No. 20, 1996 4275
considerably during the past decade,3 the reactivity of
Fischer type (low-valent) alkylidyne complexes toward
unsaturated organic substrates such as alkenes or
alkynes3d,4 has been little investigated.5 Only a few
coupling reactions of alkylidyne ligands with alkynes
and alkenes leading to carbon-carbon bond formation
have been reported,6 although the active species are
mostly transient carbene complexes formed by proto-
nation of the carbyne precursors.7
Reactivity studies with functionalized carbyne com-
plexes are much more scarce. Recently McElwee-White
and co-workers have studied8 the reactivity of acyl-
substituted and other related functionalized carbyne
complexes which undergo chemical transformations
under photooxidative and thermal conditions to give
cyclopentenones, cyclohexenones, and oxymetallacycles
depending on the carbyne substituents. This behavior
demonstrates that appropriate substitutions in the
alkylidyne group may induce substantial modifications
in the chemistry of the metal carbyne system. There-
fore, it is apparent that the utility of functionalized
metal carbyne complexes for organic transformations
has yet to be investigated. Taking into account that
among the R,â unsaturated carbene complexes the
alkenyl derivatives are some of the most efficient
synthons for synthetic applications, we believed that the
synthesis of analogous carbyne complexes would be
desirable because of the potential interest in synthesis.
halide) have been described. They have been prepared
by the classical method from the corresponding carbene
derivatives using boron halide as the Lewis acid.9 This
synthetic strategy has limited the scope of the ap-
plicability to other metallic substrates and has probably
determined that the number of unsaturated carbyne
derivatives remains still very scarce.
It is well-established that the vinylidene functionality
undergoes nucleophilic and electrophilic attacks in a
number of transition metal complexes.10 While nucleo-
philes add to the CR atom (e.g., methanol or hydride) to
give methoxycarbene and alkenyl complexes, respec-
tively, electrophiles can be added to the Câ to form
carbyne derivatives.
[M]dCdCR2 + E+ f [M]+tCCR2(E)
This latter approach provides a very simple entry to
the synthesis of alkyl and arylcarbyne complexes which
has been used to prepare a series of rhenium,11 molyb-
denum,12 iridium,13 and tungsten14 complexes. Simi-
larly an allenylidene group may also undergo electro-
philic additions to give alkenyl-carbyne derivatives.
[M]dCdC)CR2 + E+ f [M]+tCC(E)dCR2
Although this methodology seems to be a good entry
to alkenyl-substituted carbyne complexes, it has only
been applied for the synthesis of [Mn(tCCHdCR2)(η5-
C5H5)(CO)2]X (R ) But, X ) CF3COO; R ) Ph, X ) Cl,
CF3COO, BF4) which are obtained from the protonation
of allenylidene complexes [Mn(dCdCdCR2)(η5-C5H5)-
(CO)2].15a In addition analogous manganese15b,c and
rhodium16 derivatives [Mn{tCC(Me)dC(Me)(OMe)}(η5-
C5H5)(CO)(PPh3)]+, [Mn{tCC(Me)dCRR′}(η5-C5H5)-
Up to now, as far as we are aware, only cyclopentenyl
carbyne group
6 metal Fischer type complexes
[M{tCCdCH(CH2)2CH2}(CO)4X] (M ) Cr, W; X )
(2) For leading citations to the literature regarding cycloaddition
reactions, see: (a) Do¨tz, K. H.; Schafer, T.; Kroll, F.; Harms, K. Angew.
Chem., Int. Ed. Engl. 1992, 31, 1236. (b) Wulff, W. D.; Bauta, W. E.;
Kaesler, R. W.; Lankford, P. J .; Miller, R. A; Murray, C. K.; Yang, D.
C. J . Am. Chem. Soc. 1990, 112, 3642. (c) Wulff, W. D.; Bax, B. M.;
Brandvold, T. A.; Chan, K. S.; Gilbert, A. M.; Hsung, R. P. Organo-
metallics 1994, 13, 102.
(CO)(PPh3)]+, and [Rh{tCC(H)dCMe2}Cl(PPri )] have
3
also been prepared17 using proton and methyl additions
to functionalized vinylidene derivatives.
(3) (a) Fischer, H.; Hofmann, P.; Kreissl, F. R.; Schrock, R. R.;
Schubert, U.; Weiss, K. Carbyne Complexes; VCH Publishers: Wein-
heim, Germany, 1988. (b) Mayr, A. Comments Inorg. Chem. 1990, 10,
227. (c) Mayr, A.; Hoffmeister, H. Adv. Organomet. Chem. 1991, 32,
227. (d) Mayr, A.; Bastos, C. Prog. Inorg. Chem. 1992, 40, 1. (e) Engel,
P. F.; Pfeffer, M. Chem. Rev. 1995, 95, 2281.
(4) Reactions of alkylidyne ligands with carbonyl and isocyanide
ligands, carbon disulfide, and imines are well-established: (a) Kreissl,
F. R.; Frank, A.; Schubert, U.; Lindner, T. L.; Huttner, G. Angew.
Chem., Int. Ed. Engl. 1976, 15, 632. (b) Filippou, A. C.; Grunleitner,
W. Z. Naturforsch. B 1989, 44, 1023. (c) Handwerker, B. M.; Garret,
K. E.; Nagle, K. L.; Geoffroy, G. L.; Rheingold, A. L. Organometallics
1990, 9, 1562. (d) Handwerker, B. M.; Garret, K. E.; Geoffroy, G. L.;
Rheingold, A. L. J . Am. Chem. Soc. 1989, 111, 369.
(5) Stable alkylidyne alkene or alkylidyne alkyne metal complexes
have been described. (a) Mayr, A.; Dorris, A. M.; Rheingold, A. L.; Geib,
S. J . Organometallics 1990, 9, 964. (b) Bottrill, M.; Green, M.; Orpen,
A. G.; Saunders, D. R.; Williams, I. D. J . Chem. Soc., Dalton Trans.
1989, 511. (c) Atagi, L. M.; Critchlow, S. C.; Mayer, J . M. J . Am. Chem.
Soc. 1992, 114, 9223. (d) Atagi, L. M.; Mayer, J . M. Organometallics
1994, 13, 4794.
(6) (a) Hart, I. J .; J effery, J . C.; Grosse-Ophoff, M. J .; Stone, F. G.
A. J . Chem. Soc., Dalton Trans. 1988, 1867. (b) Hart, I. J .; Stone, F.
G. A. J . Chem. Soc., Dalton Trans. 1988, 1899. (c) Sivavec, T. M.; Katz,
T. J .; Chiang, M. Y.; Yang, G. X. Q. Organometallics 1989, 8, 1620. (d)
Mayr, A.; Asaro, M. F.; Glines, T. J .; Van Engen. D.; Tripp, G. M. J .
Am. Chem. Soc. 1993, 115, 8187.
(7) (a) Garrett, K. E.; Sheridan, J . B.; Pourreau, D. B.; Feng, W.
Ch.; Geoffroy, G. L.; Staley, D. L.; Rheingold, A. L. J . Am. Chem. Soc.
1989, 111, 8383. (b) Garrett, K. E.; Feng, W. C.; Matsuzaka, H.;
Geoffroy, G. L.; Rheingold, A. L. J . Organomet. Chem. 1990, 394, 251.
(c) Some high-valent alkylidyne complexes are very active for catalytic
metathesis of alkynes: Schrock, R. R. Acc. Chem. Res. 1986, 19, 342.
(8) (a) Carter, J . D.; Schoch, T. K.; McElwee-White, L. Organome-
tallics 1992, 11, 3571. (b) Mortimer, M. D.; Carter, J . D.; McElwee-
White, L. Organometallics 1993, 12, 4493. (c) Schoch, T. K.; Orth, S.
D.; Zerner, M. C.; J orgensen, K. A; McElwee-White, L. J . Am. Chem.
Soc. 1995, 117, 6475.
(9) Fischer, E. O.; Wagner, W. R.; Kreissl, F. R.; Neugebauer, D.
Chem. Ber. 1979, 112, 1320.
(10) Bruce, M. I. Chem. Rev. 1991, 91, 197.
(11) Pombeiro, A. J . L.; Hills, A.; Hughes, D. L.; Richards, R. L. J .
Organomet. Chem. 1988, 352, C5. Carvalho, M. F. N. N.; Henderson,
R. A.; Pombeiro, A. J . L.; Richards, R. L. J . Chem. Soc., Chem.
Commun. 1989, 1796.
(12) (a) Beevor, R. G.; Green, M.; Orpen, A. G.; Williams, I. D. J .
Chem. Soc., Dalton Trans. 1987, 1319. (b) Beevor, R. G.; Freeman, M.
J .; Green, M.; Morton, C. E.; Orpen, A. G. J . Chem. Soc., Dalton Trans.
1991, 3021. (c) Nicklas, P. N.; Selegue, J .; Young, B. A. Organometallics
1988, 7, 2248.
(13) (a) Ho¨hn, A.; Werner, H. Angew. Chem., Int. Ed. Engl. 1986,
737. (b) Ho¨hn, A.; Werner, H. J . Organomet. Chem. 1990, 382, 255.
(14) Birdwhitsell, K. R.; Tonker, T. L.; Templeton, J . L. J . Am. Chem.
Soc. 1985, 107, 4474.
(15) (a) Kolobova, N. E.; Ivanov, L. L.; Zhvanko, O. S.; Khitrova, O.
M.; Batsanov, A. S.; Struchkov, Y. T. J . Organomet. Chem. 1984, 262,
39. (b) Kelley, C.; Lugan, N.; Terry, M. R.; Geoffroy, G. L.; Haggerty,
B. S.; Rheingold, A. L. J . Am. Chem. Soc. 1992, 114, 6735. (c) Terry,
M. R.; Kelley, C.; Lugan, N.; Geoffroy, G. L.; Haggerty, B. S.; Rheingold,
A. L. Organometallics 1993, 12, 3607.
(16) The cationic vinylcarbyne complex [(PPri3)2(Cl)RhtCC(H)dC-
(Me)2]+ has been spectroscopically characterized by 1H NMR. Rappert,
T.; Nu¨rnberg, O.; Mahr, N.; Wolf, J .; Werner, H. Organometallics 1992,
11, 4156.
(17) Several osmium alkenylcarbyne complexes have been prepared
through reactions of substituted alkynols with dihydride-osmium(IV)
complexes: (a) Espuelas, J .; Esteruelas, M. A.; Lahoz, F. J .; Oro, L.
A.; Ruiz, N. J . Am. Chem. Soc. 1993, 115, 4683. (b) Weber, B; Steinert,
P.; Windmu¨ller, B; Wolf, J .; Werner, H. J . Chem. Soc., Chem. Commun.
1994, 2595. Thus, [OsH2Cl2(PPri3)2] and [OsH2Cl2(PPri3){κ(P)-Pri2P-
(CH2)2NMe2}] give complexes [Os(tCCHdCR1R2)HCl2(PPri3)2] (R1
)
R2 ) Me; R1 ) Me, R2 ) Et; CR1R2 ) C(CH2)4CH2)17a and [Os-
(tCCH)CPh2)HCl2(PPri3){κ(P)-Pri2P(CH2)2NMe2}],17b respectively. Alk-
enyl-carbyne complexes [Os(tCCHdCR2)Cl2{κ(P)-Pri2PCH2CO2Me}-
{κ2(P,O)-Pri2PCH2CO2}] (R ) Ph; R2 ) Me, Ph) have also been
described.17b

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4276 Organometallics, Vol. 15, No. 20, 1996
Zhang et al.
Ta ble 1. IRa a n d 1H a n d 31P {1H} NMRb Da ta for th e Tr ica r bon yl Vin ylid en e Com p lexes
m er -[(d p p e)(CO)3WdCdCHCdCH(CH2)n CH2CH2] (n ) 1 (1a ), 3 (1c), 4 (1d ))
31P{1H}
1H
IR
ν(CO)
P trans to
vinylidenec
P trans to COc
CâHd
CδHe
others
1a 2002 (m), 1924
(m), 1891 (vs)
35.9 d (1.4,f 158.5) 46.2 d
4.97 dd
5.14 br
1.85 m (CH2), 2.42 m (2 CH2), 2.57 m, 2.63 m
(1.4,f 241.9)
(4.8, 2.5)
(P(CH2)2P), 7.30-7.62 m (Ph)
1c 2001 (m), 1923
37.6 s (160.2)
47.0 s (243.3) 4.96 dd
(4.8, 2.6)
4.66 dd
(5.1, 2.4)
5.31 t (6.5) 1.37 m (CH2), 1.46 m (CH2), 1.94 m (2 CH2,
(m), 1890 (vs)
P(CH2)2P), 2.52 m (CH2), (6.62-7.42 m (Ph)
1d 2001 (m), 1924
(m), 1890 (vs)
36.6 d (2.5,f 159.9) 46.3 d
5.07 t (8.1) 1.45 m (3 CH2), 1.60 m (CH2), 2.11 m (CH2), 2.41 t
(2.5,f 242.7)
(5.9,f CH2), 2.54 m, 2.63 m (P(CH2)2P), 7.30-7.62 m (Ph)
a
b
Spectra recorded in THF, ν (cm-1). Abbreviations: m, medium; s, strong; vs, very strong. Spectra recorded in CDCl3 (1a ,d ) or C6D6
(1c). δ in ppm, J in Hz. Abbreviations: s, singlet; d, doublet; t, triplet; m, multiplet; br, broad. c J (P-W). 4J (H-P). e J (H-H). f J (P-
P).
d
Ch a r t 1
decomposition is observed over 0 °C) (eq 1). Although
(1)
As part of our ongoing studies into the chemistry of
functionalized vinylidene complexes,18 we sought to
exploit this methodology to investigate the preparation
of alkenyl-vinylidene tungsten(0) complexes. The syn-
thesis of these derivatives would provide appropriate
synthons of novel alkenyl-carbyne derivatives through
electrophilic additions.
we have not investigated the nature of the intermedi-
ates, the reactions probably proceed, as it is well-known
from other transition metal complexes,10 through π-co-
ordination of the alkynols followed by a rearrangement
to give hydroxy vinylidene species (concomitant fac f
mer tricarbonyl isomerization occurs). Subsequent de-
hydration processes proceed in a regioselective manner
(isomeric allenylidene species are not detected), leading
to the alkenyl-vinylidene complexes 1a , 1c, and 1d .
Similar transformations have been reported from iso-
electronic d6 ruthenium (II) complexes.18,19 However,
the reaction with 1-ethynylcyclohexanol (n ) 2) leads
to a mixture of the corresponding alkenyl-vinylidene
complex 1b (characterized by IR and 31P NMR; see
Experimental Section) and other unidentified species.
Attempts to isolate the vinylidene complex 1b with
analytical purity were unsuccessful.
Here we report the synthesis and characterization of
novel cationic alkenyl-carbyne tungsten complexes (A,
Chart 1) and their carbonyl-substituted derivatives (B)
(L ) PMe3, MeCN), (C) (X ) Cl, Br, I) and the
preparation of the alkenyl-vinylidene complexes (D),
which are the precursors of the alkenyl-carbyne de-
rivatives (A). 183W NMR data for the first member of
each series of compounds (n ) 1, complexes 1a -7a ) and
the first X-ray crystal structure of an alkenyl-carbyne
tungsten complex, namely trans-[(dppe)(CO)2ClWt
CCHdC(CH2)3CH2] (5a ), are also reported.
The reactions can be monitored by IR in the carbonyl
region and are allowed to proceed until total disappear-
ance of the absorptions corresponding to the starting
fac-tricarbonyl complex. IR and NMR spectra of 1a , 1c,
and 1d (Tables 1 and 2) are in accordance with this
formulation. The vinylidene ligands are identified by
Resu lts a n d Discu ssion
Alk en yl-Vin ylid en e Com p lexes. A THF solution
of fac-[W(CO)3(dppe)(Me2CO)] (dppe ) 1,2-bis(diphe-
nylphosphino)ethane) reacts with 1-ethynylcyclopen-
tanol, 1-ethynylcycloheptanol, and 1-ethynylcyclooctanol
at room temperature to give a green solution from which
alkenyl-vinylidene complexes 1a , 1c, and 1d are iso-
lated in good yields as green air-sensitive solids (slow
the characteristic low-field 13C NMR chemical shifts of
2
the CR (in the range 338.8-342.2 ppm; dd J (C-Ptrans
)
and 2J (C-Pcis) ) ca. 16 and 8 Hz, respectively). The
formation of the mer-tricarbonyl isomers is supported
by the 31P NMR spectra since two doublet signals (AB
system) appeared in the ranges of δ 35.9-37.6 and
2
46.2-47.0 ppm and confirmed by the different J (C-P)
(18) (a) Cadierno, V.; Gamasa, M. P.; Gimeno, J .; Lastra, E.; Borge,
J .; Garc`ıa-Granda, S. Organometallics 1994, 13, 745. (b) Cadierno, V.;
Gamasa, M. P.; Gimeno, J .; Borge, J .; Garc`ıa-Granda, S. J . Chem. Soc.,
Chem. Commun. 1994, 2495. (c) Cadierno, V.; Gamasa, M. P.; Gimeno,
J .; Gonzalez-Cueva, M.; Lastra, E.; Borge, J .; Garc`ıa-Granda, S.; Perez-
Carren˜o, E. Organometallics 1996, 15, 2137.
values for the vinylidene R-carbon atom. IR spectra
(THF) displaying a typical pattern of three ν(CO)
(19) Selegue, J . P.; Young, B. A.; Logan, S. L. Organometallics 1991,
10, 1972.

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Tungsten Alkenyl-Carbyne Complexes
Organometallics, Vol. 15, No. 20, 1996 4277
Ta ble 2. Selected 13C{1H} NMRa Da ta for th e Tr ica r bon yl Vin ylid en e Com p lexes
m er -[(d p p e)(CO)3WdCdCHCdCH(CH2)n CH2CH2] (n ) 1 (1a ), 3 (1c), 4 (1d ))
13C{1H}
CO cis to Pb
CO trans to Pb
others
b
c
CR
Câ
Cδ
1a 338.8 dd (15.9, 7.9) 114.4 d (12.2) 118.1 s 202.4 dd (6.4, 4.5) 211.5 dd (21.4, 8.7) 23.6 s, 32.2s , 33.8 s (3 CH2), 28.1 m, 30.3 m
(P(CH2)2P), 127.6-136.3 m (Cγ, Ph)
1c 342.2 dd (17.4, 7.9) 124.5 d (11.6) 120.9 s 204.1 dd (6.6, 4.3) 213.6 dd (21.6, 8.6) 27.8 s, 29.0 s, 29.6 s, 33.2 s, 34.0 s (5 CH2),
31.0 m (P(CH2)2P), 128.4-138.1 m (Cγ, Ph)
1d 339.2 dd (15.5, 7.3) 120.8 d (11.9) 117.4 s 202.6 dd (7.0, 4.0) 212.1 dd (21.0, 8.9) 26.2 s, 26.5 s, 26.9 s, 27.1 s, 29.0 s, 31.2 s
(6 CH2), 28.5 m (P(CH2)2P), 128.5-136.2 m (Cγ, Ph)
a
b
Spectra recorded in CDCl3 (1a ,d ) or C6D6 (1c), δ in ppm, J in Hz. Abbreviations: s, singlet; d, doublet; m, multiplet. 2J (C-P).
3J (C-P).
c
stretching absorptions are consistent with the mer-
tricarbonyl fragment. Different J (P-W) coupling con-
stants are observed for the phosphorus resonances
showing unusually small values (ca. 160 Hz) for the
high-field signals in each complex. This is consistent
with the strong trans influence of the vinylidene ligands
and with the larger J (P-W) coupling constants (ca. 242
Hz) expected for phosphorus nuclei trans to the carbonyl
ligands.20 The alkenyl-vinylidene moiety is assessed
typical of the phosphines trans to a carbonyl group with
values which can be compared to those of the corre-
sponding vinylidene complexes (ca. 242 Hz). However,
J (P-W) values of the high-field signals (97.6-98.5 Hz),
assigned to the phosphorus nucleus trans to the carbyne,
are smaller than those of the vinylidene complexes (ca.
160 Hz), reflecting the higher trans influence associated
with a carbyne ligand.21
The formation of the alkenyl-carbyne species 2a , 2c,
and 2d is dependent on the solvent. Thus, when the
protonation of the vinylidene complexes 1a , 1c, and 1d
is carried out in CH2Cl2 under similar reaction condi-
tions, a mixture of the carbyne complexes 2a , 2c, and
2d and their corresponding isomers 2a ′, 2c′, and 2d ′ is
obtained (eq 3). The yellow crystalline solids isolated
from these reactions were characterized as a ca. 1:1
mixture of the alkenyl-carbyne and the corresponding
propenyl-carbyne isomers.
1
by 13C and H NMR. Significantly, the spectra exhibit
the characteristic proton and carbon resonances of the
dCH- vinylidene and -CdCH- alkenyl groups (Tables
1 and 2).
(a ) Ca tion ic Tr ica r bon yl Ca r byn e Com p lexes.
Addition of a slight excess of HBF4 to a saturated green
solution in diethylether of neutral vinylidene complexes
1a , 1c, and 1d at -50 °C leads to the precipitation of
yellow solids identified as the corresponding cationic
alkenyl-carbyne complexes 2a , 2c, and 2d which are
isolated as the tetrafluoroborate salts (eq 2). The
cationic carbyne complexes are acidic and readily un-
dergo deprotonation when a solution in THF is treated
with NBu3 to regenerate the precursor vinylidene
complexes.
(3)
Additional signals to those assigned to complexes 2a ,
2c, and 2d can be observed in the 1H, 13C, and 31P NMR
spectra, allowing the appropriate assignments to the
isomer complexes 2a ′, 2c′, and 2d ′ (Table 3). Their
carbyne and phosphorus resonances exhibit coupling
patterns identical with those shown by alkenyl-carbyne
isomers, indicating that the mer-carbonyl geometry is
maintained. However, the chemical shifts of the car-
byne carbon nucleus are shifted to lower field (∆δ: ca.
17 ppm) while those of the phosphorus trans to the
carbyne group are shifted to higher field (∆δ: ca. 1 ppm)
with smaller values of J (P-W) (ca. 6 Hz). This seems
to indicate that the propenyl-carbyne is a moiety with
a slightly stronger trans influence than the alkenyl-
carbyne.
Although we have not studied the interconversion
processes of both isomers, we have found that alkenyl-
carbyne complexes are exclusively isolated when mix-
tures of the isomers are recrystallized from THF.
Likewise, selective formation of 2a , 2c, and 2d also
takes place when the protonation of vinylidene com-
plexes 1a , 1c, and 1d is performed in THF.
(2)
IR spectra (CH2Cl2) of 2a , 2c, and 2d show two ν-
(CO) absorptions with an intensity pattern consistent
with retention of the original mer geometry of the
carbonyl groups. Significantly, the CO stretching bands
appear (Table 3) at higher frequencies (about 70 cm-1
)
than those of the precursor vinylidene complexes,
reflecting the cationic character of the new complexes
as well as the stronger π-electron attracting properties
of the carbyne groups. 13C and 31P NMR spectra (Table
3) are also consistent with this geometry, showing, as
with the precursor vinylidene complexes, the expected
coupled signals for the carbyne carbon nucleus (δ ca.
2
303 ppm, dd, J (C-P) ) 19.2, 8.3 Hz) and phosphorus
nuclei of dppe (δ ca. 23 and 39 ppm). In particular the
phosphorus resonances exhibit the expected different
J (P-W) values (ca. 98 and 240 Hz, respectively). The
coupling constants of the low-field signals (240 Hz) are
Stirring at room temperature a CH3CN solution of
mer-tricarbonyl carbyne complexes 2a and 2d leads to
the substitution of one carbonyl ligand with concomitant
isomerization, to form trans acetonitrile carbyne dicar-
(20) (a) Pregosin, P. S., Kunz, R. W. In 31P and 13C NMR of
Transition Metal Phosphine Complexes; Pregosin, P. S., Ed.;
Springer-Verlag: Berlin, 1979. (b) Phosphorus-31 NMR Spectroscopy
in Stereochemical Analysis. Organic Compounds and Metal Complexes;
Verkade, J . G.; Quin, L. D., Eds.; VCH Publishers: Weinheim,
Germany, 1987.
(21) Shustorovich, E. M.; Poraikoshits, M. A.; Buslaev, Yu. A. Coord.
Chem. Rev. 1975, 17, 1.

+
+
4278 Organometallics, Vol. 15, No. 20, 1996
Zhang et al.
bonyl complexes trans-[(dppe)(CO)2(MeCN)WtCCHd
CCH2(CH2)nCH2CH2][BF4] 3a (n ) 1) and 3d (n ) 4)
(eq 4) which have both phosphorus atoms of dppe and
(4)
the two carbonyls cis to the carbyne ligand. The
transformation of the mer-tricarbonyl to the cis-dicar-
bonyl complexes can be monitored in solution by IR
spectroscopy which shows the typical pattern of two
strong ν(CO) stretching frequencies (2011, 1943 cm-1
(3a ); 2010, 1943 cm-1 (3d )). Total conversion is ac-
complished after ca. 12 h.
The presence of the coordinated MeCN ligand is
confirmed by the IR (KBr) spectra which show the
typical ν(CtN) absorption (2310, 2278 cm-1) and by the
proton methyl resonances in the 1H NMR spectra (δ 1.50
ppm) (Table 4). Substitution of the acetonitrile ligand
in complexes 3a , 3d by PMe3 is readily achieved yielding
trans-[(dppe)(CO)2(Me3P)WtCCHdCCH2(CH2)nCH2CH2]-
[BF4] 4a (n ) 1), 4d (n ) 4) (eq 5) which were identified
(5)
by 31P NMR spectra (Table 4). Resonances at δ 39.7
2
(4a ) (2P, d, J (P-P) ) 22.8 Hz) and 39.1 (4d ) (2P, d,
2J (P-P) ) 24 Hz) ppm are assigned to the two equiva-
lent dppe phosphorus nuclei, and those at δ -55.6 (4a )
(1P, t, 2J (P-P) ) 22.8 Hz) and -56.4 (4d ) (1P, t, 2J (P-
P) ) 24 Hz) ppm are assigned to the PMe3 ligand.
Small values of J (P-W) coupling constants of 89 Hz
associated with the PMe3 ligands are in accordance with
the trans influence of the carbyne ligands in these
complexes. 13C and 1H NMR spectra display the ex-
pected resonances for the alkenyl groups (Table 4),
indicating that the functionalization of the carbyne
moiety does not change during the substitution pro-
cesses. Significantly, carbyne carbon chemical shifts
appear at a higher field (ca. 6 and 10 ppm) with respect
to the tricarbonyl precursor complexes. This is fairly
consistent with the substitution of carbonyl groups by
the poorer π-acceptor ligands PMe3 and MeCN. Larger
shifting to higher fields are observed in the neutral
carbyne derivatives (vide infra ).
(b) Neu tr a l Ca r byn e Com p lexes. Substitution of
one carbonyl group in mer-[(dppe)(CO)3WtCCHd
CCH2(CH2)nCH2CH2][BF4] (2a , 2c, and 2d ) or the
acetonitrile ligand in trans-[(dppe)(CO)2(MeCN)Wt
CCHdCCH2(CH2)nCH2CH2][BF4] (3a , 3d ) can be easily
achieved by addition of [NBu4]X (X ) Cl, Br, I) to CH2-
Cl2 solutions of the cationic carbyne complexes affording
neutral cis-dicarbonyl halide complexes [(dppe)-
(CO)2XWtCCHdCCH2(CH2)nCH2CH2] in good yields

+
+
Tungsten Alkenyl-Carbyne Complexes
Organometallics, Vol. 15, No. 20, 1996 4279
1
Ta ble 4. Selected IRa a n d 31P {1H}, H, a n d 13C{1H} NMRb Da ta for th e Dica r bon yl Ca r byn e Com p lexesc
1H
13C{1H}
IR
ν(CO)
31P{1H}d
CâH
CH3
CR
Cγ
COe
e
3a
3d
4a
2011, 1943
2010, 1943
1999, 1934
47.1 s (233.2)
47.0 s (233.1)
5.34 br
5.03 br
5.23 br
1.50 s
292.0 t (8.9)
291.7 t (9.2)
296.9 m
169.2 s
213.5 dd (33.7, 7.1)
213.5 dd (33.5, 7.1)
212.9 m
1.50 s
168.0 s
-55.6 t (22.8,f 89.6) ,
39.7 d (22.8,f 228.3)
-56.4 t (24.0,f 91.6),
39.1 d (24.0,f 227.3)
39.1 s (228.1)
0.46 d, (9.5)g
171.1 d (1.5)h
4d
1998, 1932
5.10 br
0.54 d (9.4)g
296.9 m
171.8 s
213.3 m
5a
5b
5c
5d
6a
6d
7a
7c
7d
1999, 1929
2000, 1930
2000, 1930
1999, 1929
1999, 1929
1999, 1930
1999, 1932
1999, 1932
1998, 1931
4.78 br
4.66 br
4.62 br
4.54 br
4.95 br
4.54 br
4.91 br
4.56 br
4.56 br
269.8 t (9.9)
269.4 t (9.9)
269.8 t (10.0)
269.6 t (10.0)
269.0 t (9.7)
268.8 t (10.1)
267.3 t (9.8)
267.1 t (9.0)
266.9 t (10.2)
162.7 s
156.8 s
159.8 s
161.1 s
162.9 s
161.5 s
163.4 s
160.6 s
162.2 s
214.0 dd (44.5, 7.0)
213.7 dd (44.4, 6.7)
213.9 dd (44.4, 6.7)
214.0 dd (44.4, 6.8)
212.8 dd (42.8, 6.9)
212.9 dd (42.7, 6.7)
210.8 dd (40.1, 7.0)
210.8 dd (40.1, 7.2)
211.0 dd (40.1, 6.9)
39.3 s (228.4)
39.1 s (228.1)
39.1 s (227.8)
36.5 s (228.8)
36.4 s (228.7)
30.6 s (228.7)
30.4 s (228.6)
30.4 s (228.5)
a
b
Spectra recorded in CH2Cl2, ν (cm-1). All absorption are very strong. Spectra recorded in CDCl3, unless 1H NMR of 4a (CD2Cl2), δ
in ppm, J in Hz. Abbreviations: s, singlet; d, doublet; t, triplet; m, multiplet. c For additional data see Experimental Section. J (P-W).
d
2J (C-P). 2J (P-P). 2J (H-P). 4J (C-P).
e
f
g
h
(eq 6). Complex 5b (n ) 2; X ) Cl) is obtained directly
(6)
in low yield (25%) by treatment of the mixture contain-
ing the alkenyl-vinylidene complex mer-[(dppe)-
(CO)3WdCdCHCdCH(CH2)3CH2] (vide supra) with
HBF4 followed by the addition of [NBu4]Cl and after
chromatography workup.
IR spectra (CH2Cl2) (Table 4) show the typical two
ν(CO) carbonyl stretching absorptions in the range of
1929-2000 cm-1 for cis-dicarbonyl complexes, indicating
that the substitution takes place with isomerization of
the original geometry in the precursor mer-tricarbonyl
species. As expected from the transformation of cationic
to neutral complexes, a lowering in the absorption
frequencies (average 74 cm-1) is observed. The phos-
phorus resonances appear in the 31P NMR spectra
(Table 4) as singlet signals, indicating the chemical
equivalence of the phosphorus atoms of dppe and
therefore in accordance with this trans carbyne halide
arrangement. J (P-W) values (ca. 228.5 Hz) are similar
to those found (vide supra ) for resonances of phosphorus
nuclei trans to carbonyl ligands. Single signals are also
observed at low temperatures (ca.170 K). However, the
X-ray crystal structure determination of 5a (vide infra)
shows that the orientation of the carbyne alkenyl moiety
is such that the phosphorus atoms of dppe are chemi-
cally inequivalent in the solid state since the cyclopen-
tane ring is closer to one of them (see Figure 1).
The carbyne carbon 13C resonances of the halide
carbyne complexes trans-[(dppe)(CO)2XWtCCHd
F igu r e 1. ORTEP view of the molecular structure of the
complex [(dppe)(CO)2ClWtCCHdCCH2CH2CH2CH2] (5a )
with the atom numbering scheme. The thermal ellipsoids
are drawn at the 30% probability level.
carbyne complexes. 1H and 13C NMR spectra also
exhibit ethylene (PCH2CH2P), alkenyl (dCH-), and
methylene (-CH2-) signals of dppe and the cyclic
alkenyl-carbyne chain in accord with the proposed
structure of the complexes. In addition, the structure
of complex 5a has been determined by X-ray diffraction
methods.
The structure of complex 5a is shown in Figure 1
together with the atom numbering scheme; selected
bond distances and angles are given in Table 5. The W
atom displays a distorted octahedral coordination with
the two apical positions occupied by a Cl atom [W-Cl
) 2.540(1) Å] and by a C atom from the alkenyl-carbyne
group [W-C ) 1.830(3) Å], two cis-equatorial sites being
occupied by CO group [W-C(1) ) 2.034(4) and W-C(2)
) 2.014(3) Å] and the other two by P atoms from the
chelating dppe ligand [W-P(1) ) 2.539(1) and W-P(2)
) 2.524(1) Å]. The W atom deviates slightly [0.0748(3)
Å] from the mean plane through the four equatorial
CCH2(CH2)nCH2CH2] appear as triplet signals in the
range of δ 266.9-269.8 (2J (P-P) ca. 10 Hz) (Table 4),
which are close to the signal (δ 276.3 ppm) reported for
trans-[(dppe)(CO)2ClWtCCH2Ph]14 and at higher field
(ca. 35 ppm) than those of the corresponding cationic

+
+
4280 Organometallics, Vol. 15, No. 20, 1996
Zhang et al.
Ta ble 5. Selected Bon d Dista n ces (Å) a n d An gles
(d eg) for Com p lex 5a
monodentate ligand (eq 7). Subsequent replacement of
W-Cl
2.540(1)
2.539(1)
2.034(4)
1.846(3)
1.834(3)
1.825(3)
1.121(5)
1.432(4)
1.359(5)
1.500(7)
1.532(7)
W-C(3)
1.830(3)
2.524(1)
2.013(3)
1.846(4)
1.824(3)
1.825(3)
1.135(4)
1.511(5)
1.487(5)
1.531(7)
1.524(4)
W-P(1)
W-P(2)
W-C(1)
W-C(2)
P(1)-C(10)
P(1)-C(12)
P(1)-C(18)
O(1)-C(1)
C(3)-C(4)
C(4)-C(5)
C(6)-C(7)
C(8)-C(9)
P(2)-C(11)
P(2)-C(24)
P(2)-C(30)
O(2)-C(2)
C(5)-C(6)
C(5)-C(9)
C(7)-C(8)
C(10)-C(11)
(7)
C(2)-W-C(3)
C(1)-W-C(3)
C(1)-W-C(2)
P(2)-W-C(3)
P(2)-W-C(1)
P(1)-W-C(3)
P(1)-W-C(2)
P(1)-W-P(2)
Cl-W-C(2)
89.3(1)
90.3(1)
89.8(1)
94.3(1)
94.7(1)
94.1(1)
95.5(1)
79.7(0)
90.3(1)
88.2(1)
86.2(0)
87.5(0)
W-C(1)-O(1)
178.0(3)
176.5(3)
178.9(2)
123.3(3)
125.4(3)
124.9(3)
109.7(3)
104.7(3)
103.4(4)
104.6(4)
104.1(3)
W-C(2)-O(2)
W-C(3)-C(4)
C(3)-C(4)-C(5)
C(4)-C(5)-C(9)
C(4)-C(5)-C(6)
C(6)-C(5)-C(9)
C(5)-C(6)-C(7)
C(6)-C(7)-C(8)
C(7)-C(8)-C(9)
C(5)-C(9)-C(8)
one carbonyl group by the uncoordinated phosphorus
atom leads to the final cis-dicarbonyl carbyne complex
Cl-W-C(1)
trans-[(dppe)(CO)2ClWtCCHdC(CH2)6CH2] (5d ). The
formation of the tricarbonyl intermediate species is also
confirmed by IR in the ν(CO) stretching region, which
shows new absorptions at 2074 and 1997 cm-1 along
with that corresponding to the dicarbonyl complex 5d .
(c) 183W NMR stu d ies. 183W NMR data,23 particu-
larly on organometallic compounds, are scarce because
of the low receptivity of this nucleus (RC ) 6.08 × 10-2).
To date only one report of 183W NMR spectra of Fischer-
type24 and another one of Schrock-type tungsten car-
byne complexes25 are known in the literature. In both
cases direct observation of the transition metal was
used, a time consuming method in which applicability
is limited by the solubility and/or stability of the sample.
In all of the complexes here discussed the tungsten atom
is bonded to a bidentate phosphine ligand showing large
31P-183W coupling constants (1J (31P-183W) ) 91.6-
243.3 Hz), very suitable to be used in two-dimensional
indirect 31P, 183W recording techniques. This methodol-
ogy is based on the HMQC pulse sequence of Bax et al.,26
with additional proton decoupling throughout all the
experiment, and has been successfully exploited in the
NMR characterization of low γ nuclei.27 In this way an
increase in the signal to noise (S/N) ratio by a factor
(γP/γW)5/2, with respect to the direct 183W detection, is
predicted. Table 6 collects 183W NMR data for the series
of complexes 1a -7a having a five-membered ring in the
vinylidene or carbyne moiety. 2D 31P, 183W{1H} HMQC
correlations have been used to characterize the 183W
chemical shifts which are in the range of -2598/-1739
ppm and therefore spanning 859 ppm. The 183W NMR
spectrum of a mixture of the complexes 2a and 2a ′ is
shown in Figure 2.
Cl-W-P(2)
Cl-W-P(1)
atoms toward the C(3) atom. To the best of our
knowledge, there are no examples of structurally char-
acterized tungsten complexes in which an alkenyl-
carbyne group is present. The length of the W-C triple
bond is comparable to those found in the related
complexes [(η5-C5H5)(CO)2WtC(Tol)], 1.82(2) Å,22 and
[(η5-C5H5)(CO)2WtC(2-C4H3S)], 1.828(10) Å,7b in which
the W atoms shows a three-legged piano-stool coordina-
tion. Of note is the remarkable carbyne trans influence,
the value of the W-Cl bond length being much longer
than the average one found in about 80 hexacoordinate
tungsten complexes [2.388 Å, from Cambridge Crystal-
lographic Data Base].
The pentaatomic ring displays a twist conformation
with the C(7) and C(8) atoms out of the mean plane
through the WC(3)C(4)C(5)C(6)C(9)H(4) fragment by
-0.314(7) and 0.242(6) Å, respectively. This plane
forms angles of 21.0(2) and 74.0(1)° with the W-C(2)
and W-C(1) lines, respectively.
In order to study the mechanism of the isomerization
involved in the formation of these complexes, we have
monitored by 31P NMR the reaction of mer-[(dppe)-
(CO)3WtCCHdC(CH2)6CH2][BF4] (2d ) with [NBu4]Cl
in CH2Cl2. The first reaction step is apparently very
fast since after 5 min the signals of the starting mer-
tricarbonyl complex at δ 23.3 and 39.0 ppm are no
longer observed. Instead new signals appear: a singlet
at δ 39.3, assigned to the final carbyne dicarbonyl
complex 5d , and two doublets at δ 15.5 and -11.9 ppm
(3J (P-P) ) 39 Hz), a typical pattern for a monodentate
coordination of dppe. After ca. 60 min the spectrum
only shows the singlet signal of 5d at 39.3 ppm. We
believe that the substitution proceeds through the
dissociation of the phosphorus atom trans to the carbyne
group and concomitant coordination of the entering
chloride ligand to give a not isolated intermediate
species, mer-[{κ(P)-Ph2P(CH2)2PPh2}(CO)3ClWtCCHd
The substitution of one carbonyl ligand in the alk-
enyl-carbyne complex 2a by PMe3, CH3CN, or halides
(23) (a) Minelli, M.; Enemark, J . H.; Brownlee, R. T. C.; O’Connor,
M. J .; Wedd, A. G. Coord. Chem. Rev. 1985, 68, 169. (b) Brevard, C.;
Thouvenot, R. In Transition Metal Nuclear Magnetic Resonance;
Pregosin, P. S., Ed.; Elsevier: Amsterdam, 1991; p 82.
(24) Sekino, M.; Sato, M.; Nagasawa, A.; Kikuchi, K. Organometal-
lics 1994, 13, 1451.
(25) Young, C. G.; Kober, E. M.; Enemark, J . H. Polyhedron 1987,
6, 255.
(26) Bax, A.; Griffey, R. H.; Hawkins, B. I. J . Magn. Reson. 1983,
55, 301
(27) (a) Benn, R.; Brenneke, H.; Heck, J .; Rufinska, A. Inorg. Chem.
1987, 26, 2826. (b) Benn, R.; J oussen, E.; Lehmkuhl, H.; Lo´pez-Ortiz,
F.; Rufinska, A. J . Am. Chem. Soc. 1989, 111, 8754. (c) Benn, R.;
Brenneke, H.; J oussen, E.; Lehmkuhl, H.; Lo´pez-Ortiz, F. Organome-
tallics 1990, 9, 756, and references cited therein.
C(CH2)6CH2] in which the phosphine is acting as a
(22) Fischer, E. O.; Lindner, T. L.; Huttner, G.; Friedrich, P.; Kreissl,
F. R.; Besenhard, J . O. Chem. Ber. 1977, 110, 3397.

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Tungsten Alkenyl-Carbyne Complexes
Organometallics, Vol. 15, No. 20, 1996 4281
Ta ble 6. δ183W Ch em ica l Sh ifts of th e Com p ou n d s
1a -7a
total shielding constant σ given by the Ramsey equa-
tion30
compound
δ(183W)a
compound
δ(183W)a
σ ) σp + σd
1a
2a
2a ′
3a
-2596
-2218
-2262b
-1786
4a
5a
6a
7a
-2018
-1739
-1786
-1891
Assuming that the σp term is dominated by the
average electronic excitation energy, σp (∆ꢀ)-1, then
the observed δ(183W) can be rationalized according to
the ligand π-bonding ability. A good π-acceptor ligand
is able to stabilize the filled d-orbitals of the metal
through back-bonding and consequently ∆ꢀ will increase
to give a high field metal chemical shift. The downfield
shifting of 183W resonances observed for complexes 2a -
7a (Table 6) as the π-back-donation becomes smaller31
is in accordance with the well-known π-acceptor ability
of the ligands CO > PMe3 > CH3CN g halide. On the
other hand, it is interesting to note the 378 ppm 183W
deshielding of 2a with respect to 1a which can be
ascribed to the different π-acceptor properties of the
alkenyl-carbyne vs the alkenyl-vinylidene moieties
and the cationic nature of complex 2a .
a
b
Referred to Na2WO4. Measured from a sample containing a
40:60 mixture of 2a :2a ′.
Con clu d in g Rem a r k s
F igu r e 2. 161.98 MHz 31P, 183W{1H} HMQC spectrum of
a mixture of 2a and 2a ′ in a ratio of 40:60. The dephasing
delay of 1J (P-W) was set to 2.9 ms, and 112 t1 increments
were recorded with an accumulation of 128 scans each. The
spectrum was acquired in the TPPI mode without refocus-
ing. Negative cross peaks are represented by dotted lines.
All other parameters were as described in the Experimen-
tal Section.
Novel alkenyl-vinylidene tungsten(0) complexes mer-
[(dppe)(CO)3WdCdCHCdCH(CH2)nCH2CH2] (dppe )
1,2-bis(diphenylphosphino)ethane) have been prepared
in good yields. In this work we have developed an
efficient route for the synthesis of cationic alkenyl-
carbyne
complexes
mer-[(dppe)(CO)3WtCCHd
CCH2(CH2)nCH2CH2][BF4] from the vinylidene deriva-
tives which undergo regioselective electrophilic addition
of protons, in diethyl ether or THF as solvents, at the
Cδ of the alkenyl-vinylidene moiety. These alkenyl-
carbyne complexes have proven to be good precursors
for the high-yield preparation of an extensive series of
derivatives: a) cationic derivatives trans-[(dppe)(CO)2-
to give the complexes 3a -7a leads to a deshielding of
the 183W nucleus (Table 6). Complexes 5a -7a exhibit
a “normal halogen dependence” with a small δ(183W)
difference between the chloride and bromide complexes
and larger shielding effect in the iodide derivative. A
similar trend has been observed in W(II) carbonyl
complexes.28 It is worth mentioning the upfield shift
of 296 ppm shown by the alkenyl-carbyne complex 5a
(δ -1739 ppm) compared to the resonance of the
analogous compound24 [(dppf)(CO)2ClWtCC6H5] (dppf)
1,1’-bis(diphenylphosphino)ferrocene) (δ -1443 ppm).
Although it has been claimed that similar electronic
effects are expected for dppf and other similar bidentate
phosphines,24 in fact, when the δ(183W) of [W(CO)6] (δ
-3483 ppm), [W(CO)4(dppe)] (δ -3291 ppm) and
[W(CO)4(dppf)] (δ -3023 ppm) are compared, it is found
that dppf has a deshielding effect 268 ppm larger than
dppe. Introducing this correction value for the com-
parison of the 183W chemical shifts of complexes 5a (δ
-1739 ppm) and [(dppf)(CO)2ClWtCC6H5] (δ -1443
ppm), a net high-field shift of only 28 ppm is obtained
for the former. Providing that structural effects can be
neglected, since similar pseudooctahedron geometry
around the tungsten atoms are shown by the X-ray
crystal structures of both complexes, the difference in
the shielding can be attributed to the substituents in
the carbyne moieties.
LWtCCHdCCH2(CH2)nCH2CH2][BF4] (L ) CH3CN,
PMe3; n ) 1, 4) and (b) neutral ones trans-[(dppe)(CO)2-
XWtCCHdCCH2(CH2)nCH2CH2] (X ) Cl, n ) 1-4; X
) Br, n ) 1, 4; X ) I, n ) 1, 3, 4) which have been
prepared by conventional carbonyl substitution reac-
tions. 31P{1H} and 183W NMR studies on analogous
members of these series allow one to get information
on the trans influence and the electronic nature of the
unsaturated carbyne and carbene moieties. In this
1
regard J (P-W) values reveal unusually low values (ca.
90 Hz) for the alkenyl-carbyne groups compared to
those for alkenyl-vinylidene moieties (ca. 160 Hz) and
carbonyl ligands (ca. 240 Hz), indicating a high trans
influence of the carbyne group. The coupling constants
found in the carbyne complexes are the lowest ever
reported along with that shown by a cyclopentadienyl
bridged binuclear complex.27a This supports the mech-
anism of the substitution reactions in the tricarbonyl
alkenyl-carbyne complexes in which a dissociation of
the phosphorus atom of dppe, trans to the carbyne
For heavy nuclei the chemical shift is largely con-
trolled by the paramagnetic contribution29 (σp) to the
(29) (a) J ameson, C. J .; Mason, J . In Multinuclear NMR; Mason, J .,
Ed.; Plenum Press: New York, 1987; Chapter 2, p 51. (b) Rehder, D.
In Multinuclear NMR; Mason, J ., Ed.; Plenum Press: New York, 1987;
Chapter 19, p 479.
(30) (a) Ramsey, N. F. Phys. Rev. 1950, 77, 567. (b) Ramsey, N. F.
Phys. Rev. 1950, 78, 699.
(28) (a) McFarlane, H. C. E.; McFarlane, W.; Rycroft, D. S. J . Chem.
Soc., Dalton Trans. 1976, 1616. (b) Benn, R.; Rufinska, A.; King, M.
A.; Osterberg, C. E.; Richmond, T. J . Organomet. Chem. 1989, 376,
359. (c) W(VI) complexes show an inverse halogen dependence, Ma,
Y.; Demou, P.; Faller, J . W. Inorg. Chem. 1991, 30, 62.
(31) Andrews, G. T.; Colquhoun, I. J .; McFarlane, W. J . Chem. Soc.,
Dalton Trans. 1982, 2353.

+
+
4282 Organometallics, Vol. 15, No. 20, 1996
Zhang et al.
fa c-[W(CO)3(d p p e)(Me2CO)]. A mixture of [W(CO)6] (0.25
g, 0.7 mmol) and dppe (0.3 g, 0.7 mmol) in 75 mL of acetone
was irradiated by a high-pressure Hg lamp (450 W). The
reaction was monitored by IR in the ν(CO) region. The
irradiation was discontinued (ca. 10 h) when absorptions of
W(CO)5(dppe) and W(CO)4(dppe) were no longer observed. The
resulting deep yellow solution was transferred via stainless
steel tubing to a Schlenk flask and the solvent removed under
vacuum. The yellow solid residue was triturated and washed
with 2 × 10 mL of a 3:1 hexane-diethylether mixture to give
a yellow powder of fac-[W(CO)3(dppe)(Me2CO)] which was
dried under vacuum. The yield was nearly quantitative, but
the solid was contaminated with traces of [W(CO)4(dppe)].
Nevertheless this material was used without further purifica-
tion for the subsequent syntheses.
moiety, is proposed as the first step of the reactions.
Even though a clear relationship between oxidation
state and 183W chemical shifts in tungsten complexes
has not been established,23 we have found that there is
a significant downfield shifting of 183W resonances for
the formally W(II) carbyne complexes compared to the
analogous W(0) vinylidene derivatives.
In summary, in this work a systematic and simple
entry for the preparation of alkenyl-carbyne tungsten
complexes is described. Since the analogous R,â unsat-
urated carbene derivatives are currently one of the most
important synthons in organic synthesis, the novel
carbyne derivatives provide appropriate substrates for
similar reactivity studies.
m er -[(d p p e)(CO)3WdCdCHCdCH(CH2)n CH2CH2] (n )
1 (1a ), 3 (1c), 4 (1d )). Gen er a l P r oced u r e. A mixture of
fac-[W(CO)3(dppe)(Me2CO)] (0.50 g, 0.69 mmol) and the cor-
responding alkynol (1.4 mmol) in 5 mL of tetrahydrofuran
(THF) was stirred overnight (ca. 10-12 h) at room tempera-
ture. The color of the solution changed from deep brown to
deep green. After the solvent was removed, the resulting green
tar residue was extracted with diethyl ether at -20 °C.
Removal of the solvent and washing with hexane at -20 °C
gave the desired compounds as green solids. Yield: 1a , 73%;
1c, 30%; 1d , 73%. Mass spectrum and analytical data for 1a :
MS (FAB, m/e) [M+] ) 759, [M+ - CO] ) 731. Anal. Calcd
for C36H32O3P2W: C, 57.01; H, 4.25. Found: C, 56.75; H, 4.38.
Analytical data for 1c: Anal. Calcd for C38H36O3P2W: C,
58.03; H, 4.61. Found: C, 59.17; H, 4.18. Mass spectrum and
analytical data for 1d : MS (FAB, m/e) [M+] ) 801, [M+ - CO]
) 773. Anal. Calcd for C39H38O3P2W: C, 58.52; H, 4.78.
Found: C, 58.69; H, 4.56.
Exp er im en ta l Section
The reactions were carried out under dry nitrogen using
Schlenk techniques. All solvents were dried by standard
methods and distilled under nitrogen before use. The complex
fac-[W(CO)3(dppe)(Me2CO)] was prepared as reported in the
literature by a modified method.32 Tungsten hexacarbonyl
(Strem Chemicals), alkynols (Lancaster Chemical Co.), and
HBF4‚OEt2, PMe3, and [NBu4]X (X) Cl, Br, I) (Aldrich Chemi-
cal Co.) were used as received.
Infrared spectra were recorded on a Perkin-Elmer 1720-XFT
spectrometer. Mass spectra (FAB) were recorded using a VG-
Autospec spectrometer, operating in the positive mode; 3-ni-
trobenzyl alcohol (NBA) was used as the matrix. The conduc-
tivities were measured at room temperature, in ca. 10-3 mol
dm-3 acetone solutions, with a J enway PCM3 conductivimeter.
The C, H, and N analyses were carried out with a Perkin-
Elmer 240-B microanalyzer.
mer -[(dppe)(CO)3WtCCHdCCH2(CH2)nCH2CH2][BF4] (n
) 1 (2a ), 3 (2c), 4 (2d )). Gen er a l P r oced u r e. A green
saturated solution (0.5 mmol) of 1a -1d in diethyl ether was
cooled to -50 °C, and 60 µL (0.5 mmol) of HBF4‚OEt2 (80%
(w/w) in diethyl ether) was added by syringe. The mixture
was stirred at -50 °C for 0.5 h and then allowed to warm to
-5 °C, leading to the precipitation of a yellow solid. Removal
of the solvent and washing the resulting solid with cold diethyl
ether (3 × 10 mL) gave the desired compounds 2a , 2c, and 2d
as yellow solids. Yield: 2a , 86%; 2c, 80%; 2d , 84%. Conduc-
tivity (acetone, 20 °C, Ω-1 cm2 mol-1): 2a , 114; 2c, 122; 2d ,
109. Spectral and analytical data for 2a : IR (KBr, ν(BF)) 1059
(s, br). MS (FAB, m/e) [M+ - BF4] ) 759, [M+ - BF4 - 2CO]
) 731. Anal. Calcd for C36H33BF4O3P2W: C, 51.10; H, 3.93.
Found: C, 50.80; H, 4.03. Spectral and analytical data for
2c: IR (KBr, ν(BF)) 1057 (s, br). MS (FAB, m/e) [M+ - BF4]
NMR spectra were run on Bruker AC300 and AMX400
spectrometers. The AC300 instrument was configured with
a triple probe (1H, 13C, 31P). The AMX400 instrument was
equipped with a third radiofrequency channel. A 5 mm reverse
triple probe head was used. The inner coil was doubly tuned
1
for H and 31P, and the outer coil was tunable in the frequency
range 18-160 MHz. Even though at 9.4 T the frequency of
the 183W nucleus lies outside the specifications of the probe, it
could be tuned so that a pulse of a reasonable width was
obtained. The pulse widths for the 90° pulses and operating
frequencies were as follows: 10.4/13.0 µs (1H, 400/300 MHz),
14.5/7.0 µs (13C, 100.6/75.5 MHz), 14.5/10 µs (31P, 161.98/121.5
MHz), and 53 µs (183W, 16.65 MHz). The attenuation levels
used in the AMX400 apparatus were 5 dB for the proton
channel and 3 dB for the heteronuclei. The spectral references
used were tetramethylsilane for 1H and 13C, 85% H3PO4 for
31P, and Na2WO4 for 183W.
) 787, [M+ - BF4 - 2CO] ) 759. Anal. Calcd for C38H37
-
BF4O3P2W: C, 52.20; H, 4.26. Found: C, 54.16; H, 4.55.
Spectral and analytical data for 2d : IR (KBr, ν(BF)) 1059 (s,
br). MS (FAB, m/e) [M+ - BF4] ) 801, [M+ - BF4 - 2CO] )
773. Anal. Calcd for C39H39BF4O3P2W: C, 52.73; H, 4.42.
Found: C, 52.10; H, 4.37.
Selected spectral parameters in the AMX400 spectrometer
were as follows. One-dimensional 1H NMR: 32 K data points;
spectral width 4000 Hz. 13C NMR: 64 K data point; spectral
width 36 000; exponential multiplication with a line broaden-
ing factor of 1 Hz. 31P NMR: 32 K data points; spectral width
3500 Hz; exponential line broadening of 1 Hz. 31P, 183W{1H}
2D HMQC: spectral width, 3500 Hz in F2 and 1000 Hz in F1;
96 increments recorded; final matrix after zero filling, 1024 ×
t r a n s-[(d p p e )(C O )2 (Me C N )WtC C H dC C H 2 (C H 2 )n -
CH2CH2][BF 4] (n ) 1 (3a ), 4 (3d )). Gen er a l P r oced u r e. A
yellow solution of 2a or 2d (0.24 mmol) in 20 mL of acetonitrile
was stirred overnight (ca. 12 h) at room temperature. Removal
of the solvent and washing the residue with diethyl ether gave
3a and 3d as yellow solids. Yield: 3a , 84%; 3d , 91%.
Conductivity (acetone, 20 °C, Ω-1 cm2 mol-1): 3a , 110; 3d , 125.
Spectral and analytical data for 3a : IR (KBr, ν(CtN), ν(BF))
2310 (vw), 2278 (vw), 1062 (s, br). 1H NMR (δ, CDCl3) 1.19
(m, 2H, CH2), 1.50 (m, 4H, 2CH2), 2.05 (m, 2H, CH2), 2.55 (m),
3.17 (m, 4H, P(CH2)2P), 7.32-7.71 (m, 20H, PPh2). 13C{1H}
NMR (δ, CDCl3) 1.9 (s, NCCH3), 25.5 (s, CH2), 26.1 (s, CH2),
27.2 (m, P(CH2)2P), 32.2 (s, CH2), 34.7 (s, CH2), 127.8-135.6
(m, Câ, NCCH3, PPh2). MS (FAB, m/e) [M+] ) 859, [M+ - BF4
- NCMe] ) 731, [M+ - BF4 - NCMe - 2CO] ) 675. Anal.
1
256; evolution delay of J (P-W), 2.2 ms; 80 scans per incre-
ment in F1; TPPI mode; qsine multiplication of π/2 in both
dimensions prior to transformation. In each case a first
experiment with a large sweep width in F1 was run (up to
50 000 Hz). Subsequently, the spectral window of the tungsten
nucleus was reduced to 1000 Hz to ensure that no folding in
the F1 dimension occurred and to improve the digital resolu-
tion.
1H, 13C{1H}, 31P{1H}, and 183W NMR spectroscopic data for
the alkenyl-vinylidene and alkenyl-carbyne complexes are
collected in Tables 1-4 and 6.
(32) Schenk, W. A.; Muller, H. Chem. Ber. 1982, 115, 3618.

+
+
Tungsten Alkenyl-Carbyne Complexes
Organometallics, Vol. 15, No. 20, 1996 4283
Calcd for C37H36BF4NO2P2W: C, 51.72; H, 4.22; N, 1.63.
Found: C, 51.74; H, 4.43; N, 1.35. Spectral and analytical data
for 3d : IR (KBr, ν(CtN), ν(BF)) 2313 (vw), 2278 (vw), 1063
(s, br). 1H NMR (δ, CDCl3) 1.41 (m, 8H, 4 CH2), 1.73 (m, 2H,
CH2), 1.91 (m, 2H, CH2), 2.43 (m, 2H, CH2), 2.55 (m), 3.18 (m,
4H, P(CH2)2P), 7.31-7.71 (m, 20H, PPh2). 13C{1H} NMR (δ,
CDCl3) 1.7 (s, NCCH3), 25.3 (s, CH2), 26.7 (br, 4 CH2), 27.2
(m, P(CH2)2P), 32.0 (s, CH2), 35.6 (s, CH2), 128.6-134.6 (m,
Câ, NCCH3, PPh2). MS (FAB, m/e) [M+ - BF4 - NCMe] )
773. Anal. Calcd for C40H42BF4NO2P2W: C, 53.30; H, 4.70;
N, 1.55. Found: C, 52.71; H, 4.84; N, 0.87.
tr a n s-[(d p p e)(CO)2Br WtCCHdCCH2(CH2)n CH2CH2] (n
) 1 (6a ), 4 (6d )). Gen er a l P r oced u r e. A yellow solution of
2a or 2d (0.2 mmol) and 1 equiv of [NBu4]Br in 10 mL of
dichloromethane was heated at reflux for 2 h. The mixture
was worked up as described above for isolation of 5a , 5c, and
5d to yield the desired compounds 6a and 6d as bright yellow
solids. Yield: 6a , 90%; 6d , 90%. Spectral and analytical data
for 6a : 1H NMR (δ, CDCl3) 1.48 (m, 4H, 2 CH2), 1.91 (m, 2H,
CH2), 2.02 (m, 2H, CH2), 2.54 (m), 2.94 (m, 4H, P(CH2)2P),
7.32-7.71 (m, 20H, PPh2). 13C{1H} NMR (δ, CDCl3) 25.7 (s,
CH2), 26.2 (s, CH2), 27.1 (m, P(CH2)2P), 31.6 (s, CH2), 34.4 (s,
CH2), 128.2-136.2m (Câ, PPh2). MS (FAB, m/e) [M+ - Br] )
731, [M+ - 2CO] ) 755. Anal. Calcd for C35H33BrO2P2W: C,
51.81; H, 4.10. Found: C, 51.60; H, 4.20. Spectral and
analytical data for 6d : 1H NMR (δ, CDCl3) 1.40 (m, 8H, 4 CH2),
1.72 (m, 4H, 2 CH2), 2.34 (m, 2H, CH2), 2.49 (m), 2.88 (m, 4H,
P(CH2)2P), 7.25-7.65 (m, 20H, PPh2). 13C{1H} NMR (δ, CDCl3)
25.6 (s, CH2), 26.7-27.6 (m, 4 CH2, P(CH2)2P), 31.7 (s, CH2),
36.0 (s, CH2), 128.2-136.2 (m, Câ, PPh2). MS (FAB, m/e) [M+
tra ns-[(dppe)(CO)2(Me3P )WtCCHdCCH2(CH2)nCH2CH2]-
[BF 4] (n ) 1 (4a ), 4 (4d )). Gen er a l P r oced u r e. 1 equiv
amount of PMe3 was added at room temperature by syringe
to a yellow solution of 3a or 3d (0.2 mmol) in 10 mL of
dichloromethane. The substitution was accomplished in 5 min
and could be monitored by IR (ν(CO) stretching range).
Removal of the solvent and washing of the residue with diethyl
ether gave the desired compounds 4a and 4d as yellow solids.
Yield: 4a , 87%; 4d , 87%. Conductivity (acetone, 20 °C, Ω-1
cm2 mol-1): 4a , 128; 4d , 122. Spectral and analytical data
for 4a : IR (KBr, ν(BF)) 1059 (s, br). 1H NMR (δ, CD2Cl2) 1.34
(m, 2H, CH2), 1.46 (m, 2H, CH2), 1.78 (m, 2H, CH2), 2.05 (m,
2H, CH2), 2.72 (m), 3.04 (m, 4H, P(CH2)2P), 7.30-7.61 (m, 20H,
PPh2). 13C{1H} NMR (δ, CDCl3) 15.0 (d, J (C-P) ) 23.2 Hz,
P(CH3)3), 25.2 (s, CH2), 26.1 (s, CH2), 26.4 (m, P(CH2)2P), 32.4
(s, CH2), 35.2 (s, CH2), 128.6-135.2 (m, Câ, PPh2). MS (FAB,
m/e) [M+ - BF4] ) 807, [M+ - BF4 - PMe3] ) 731. Anal. Calcd
for C38H42BF4O2P3W: C, 51.04; H, 4.73. Found: C, 51.48; H,
4.19. Spectral and analytical data for 4d : IR (KBr, ν(BF))
1058 (s, br). 1H NMR (δ, CDCl3) 1.51 (m, 8H, 4 CH2), 1.79 (m,
2H, CH2), 2.03, (m, 2H, CH2), 2.54 (m, 2H, CH2), 2.80 (m), 3.33
(m, 4H, P(CH2)2P), 7.35-7.84 (m, 20H, PPh2). 13C{1H} NMR
(δ, CDCl3) 14.9 (d, J (C-P) ) 23.0 Hz, P(CH3)3), 25.4 (s, CH2),
25.9 (s, CH2), 26.4 (s, CH2), 26.5 (m, P(CH2)2P), 27.1 (s, CH2),
28.0 (s, CH2), 32.6 (s, CH2), 35.8 (s, CH2), 128.1-135.2 (m, Câ,
PPh2). MS (FAB, m/e) [M+ - BF4] ) 849, [M+ - BF4 - PMe3]
) 773. Anal. Calcd for C41H48BF4O2P3W: C, 52.59; H, 5.17.
Found: C, 50.84; H, 5.38.
- Br] ) 773, [M+ - 2CO] ) 798. Anal. Calcd for C38H39
-
BrO2P2W: C, 53.48; H, 4.61. Found: C, 53.32; H, 4.82.
tr a n s-[(d p p e)(CO)2IWtCCHdCCH 2(CH2)n CH2CH2] (n
) 1 (7a ), 3 (7c) 4 (7d )). Gen er a l P r oced u r e. A yellow
solution of 2a , 2c, or 2d (0.2 mmol) and 1 equiv of [NBu4]I in
10 mL of dichloromethane was heated at reflux for 5 h. The
mixture was worked up as described above for isolation of 5a ,
5c, and 5d to yield the desired compounds 7a , 7c, and 7d as
bright yellow solids. Yield: 7a , 86%; 7c, 71%; 7d , 89%.
Spectral and analytical data for 7a : 1H NMR (δ, CDCl3) 1.53
(m, 4H, 2 CH2), 1.88 (m, 2H, CH2), 2.01 (m, 2H, CH2), 2.57
(m), 3.00 (m, 4H, P(CH2)2P), 7.33-7.71 (m, 20H, PPh2). 13C-
{1H} NMR (δ, CDCl3) 25.7 (s, CH2), 26.2 (s, CH2), 27.4 (m,
P(CH2)2P), 32.0 (s, CH2), 34.8 (s, CH2), 128.1-136.4 (m, Câ,
PPh2). MS (FAB, m/e) [M+ - 2CO] ) 802, [M+ - I] ) 731.
Anal. Calcd for C35H33IO2P2W: C, 48.98; H, 3.88. Found: C,
49.46; H, 3.99. Spectral and analytical data for 7c: 1H NMR
(δ, CDCl3) 1.37 (m, 8H, 4 CH2), 1.80 (m, 2H, CH2), 2.24 (m,
2H, CH2), 2.50 (m), 2.95 (m, 4H, P(CH2)2P), 7.24-7.63 (m, 20H,
PPh2). 13C{1H} NMR (δ, CDCl3) 26.8-32.2 (m, 3 CH2,
P(CH2)2P), 29.4 (s, CH2), 32.8 (s, CH2), 37.6 (s, CH2), 128.2-
136.2 (m, Câ, PPh2). MS (FAB, m/e) [M+ - 2CO] ) 830, [M+
- I] ) 760. Anal. Calcd for C37H37IO2P2W: C, 50.14; H, 4.21.
Found: C, 50.66; H, 4.60. Spectral and analytical data for
7d : 1H NMR (δ, CDCl3) 1.48 (m, 8H, 4 CH2), 1.83 (m, 4H, 2
CH2), 2.44 (m, 2H, CH2), 2.58 (m), 3.04 (m, 4H, P(CH2)2P),
7.34-7.72 (m, 20H, PPh2). 13C{1H} NMR (δ, CDCl3) 25.5 (s,
CH2), 26.6-29.7 (m, 4 CH2, P(CH2)2P), 31.9 (s, CH2), 36.3 (s,
CH2), 126.8-136.2 (m, Câ, PPh2). MS (FAB, m/e) [M+ - 2CO]
) 844, [M+ - I] ) 773. Anal. Calcd for C38H39IO2P2W: C,
50.69; H, 4.37. Found: C, 51.61; H, 4.63.
tr a n s-[(d p p e)(CO)2ClWtCCHdCCH2(CH2)n CH2CH2] (n
) 1 (5a ), 3 (5c), 4 (5d )). Gen er a l P r oced u r e. A yellow
solution of 2a , 2c, or 2d (0.2 mmol) and 1 equiv of [NBu4]Cl
in 10 mL of dichloromethane was stirred at room temperature
for 2 h. After evaporation of the solvent to dryness the residue
was extracted with toluene and filtered off on Alox. Removal
of the solvent gave the desired compounds 5a , 5c, and 5d as
bright yellow solids. Yield: 5a , 89%; 5c, 74%; 5d , 90%.
Spectral and analytical data for 5a : 1H NMR (δ, CDCl3) 1.38
(m, 4H, 2 CH2), 1.85 (m, 2H, CH2), 1.94 (m, 2H, CH2), 2.49
(m), 2.78 (m, 4H, P(CH2)2P), 7.27-7.65 (m, 20H, PPh2). 13C-
{1H} NMR (δ, CDCl3) 25.7 (s, CH2), 26.2 (s, CH2), 27.2 (m,
P(CH2)2P), 31.4 (s, CH2), 34.2 (s, CH2), 128.2-133.0 (m, Câ,
PPh2). MS (FAB, m/e) [M+ - Cl] ) 731, [M+ - 2CO] ) 711.
Anal. Calcd for C35H33ClO2P2W: C, 54.82; H, 4.34. Found:
C, 54.06; H, 4.33. Spectral and analytical data for 5c: 1H NMR
(δ, CDCl3) 1.34 (m, 8H, 4 CH2), 1.79 (m, 2H, CH2), 2.23 (m,
2H, CH2), 2.50 (m), 2.80 (m, 4H, P(CH2)2P), 7.28-7.66 (m, 20H,
PPh2). 13C{1H} NMR (δ, CDCl3) 27.1 (s, CH2), 27.2 (m,
P(CH2)2P), 27.6 (s, CH2), 29.3 (s, CH2), 30.0 (s, CH2), 32.3 (s,
CH2), 37.1 (s, CH2), 128.2-136.2 (m, Câ, PPh2). MS (FAB, m/e)
[M+ - Cl] ) 760, [M+ - 2CO] ) 739. Anal. Calcd for
tr a n s-[(dppe)(CO)2ClWtCCHdCCH2(CH2)2CH2CH2] (5b).
A mixture of fac-[W(CO)3(dppe)(Me2CO)] (0.18 g, 0.25 mmol)
and 1-ethynylcyclohexanol (62 mg, 0.5 mmol) in 2 mL of
tetrahydrofuran (THF) was stirred for 6 h at room tempera-
ture. After the solvent was removed, the resulting green
brown tar residue was extracted with diethyl ether at -50 °C.
Removal of the solvent and washing of the residue with cold
hexane (2 × 5 mL) yielded a pale green solid. It was identified
as
a mixture of mer-[(dppe)(CO)3WdCdCHCdCH(CH2)2-
CH2CH2] (1b) with other unidentified products. 1b: IR (THF,
ν(CO)) 1999 (w), 1922 (m), 1886 (vs). 31P{1H} NMR (δ, THF-
D2O): 37.7 (s, J (P-W) ) 164.5), 46.5 (s, J (P-W) ) 240.5). The
above solid was dissolved in diethyl ether and 21 µL (0.25
mmol) of HBF4‚OEt2 (80% (w/w) in diethyl ether) was added
by syringe. The mixture was stirred at -50 °C for 0.5 h and
then allowed to warm to -5 °C, leading to the precipitation of
a yellow solid. Removal of the solvent and washing the
resulting solid with cold diethyl ether (5 mL) and hexane (2 ×
5 mL) gave a pale yellow solid. A yellow solution of this
C
37H37ClO2P2W: C, 55.90; H, 4.69. Found: C, 56.20; H, 4.80.
Spectral and analytical data for 5d : 1H NMR (δ, CDCl3) 1.35
(m, 8H, 4 CH2), 1.69 (m, 4H, 2 CH2), 2.30 (m, 2H, CH2), 2.50
(m), 2.80 (m, 4H, P(CH2)2P), 7.26-7.66m (20H, PPh2). 13C-
{1H} NMR (δ, CDCl3) 25.6 (s, CH2), 26.8 (s, CH2), 26.89 (s,
CH2), 26.92 (s, CH2), 26.97 (s, CH2), 27.2 (m, P(CH2)2P), 31.5
(s, CH2), 35.8 (s, CH2), 128.2-135.7 (m, Câ, PPh2). MS (FAB,
m/e) [M+ - Cl] ) 773, [M+ - 2CO] ) 752. Anal. Calcd for
C
38H39ClO2P2W: C, 56.42; H, 4.86. Found: C, 56.47; H, 4.89.

+
+
4284 Organometallics, Vol. 15, No. 20, 1996
Zhang et al.
Ta ble 7. Exp er im en ta l Da ta for th e X-r a y
Diffr a ction Stu d ies of Com p lex 5a
100 measurements; no significant decay was noticed over the
time of data collection. Intensities were corrected for Lorentz
and polarization effects. A correction for absorption was
applied (maximum and minimum values for the transmission
factors were 1.0 and 0.648).33
formula
C35H33ClO2P2W
766.90
Mr
cryst system
space group
radiation (λ, Å)
triclinic
P1h
The structure was solved by Patterson and Fourier methods
and refined by full-matrix least-squares, first with isotropic
thermal parameters and then with anisotropic thermal pa-
rameters for the non-hydrogen atoms. All hydrogen atoms
were clearly localized in the final ∆F map and refined
isotropically. The final cycles of refinement were carried out
on the basis of 472 variables; after the last cycles, no
parameters shifted by more than 0.7 esd. The highest remain-
ing peak in the final difference map was equivalent to about
1.06 e/Å3. In the final cycles of refinement a weighting scheme
graphite-monochromated
(Mo KR, 0.710 73)
10.629(3)
15.808(5)
10.285(4)
107.21(1)
95.24(1)
a, Å
b, Å
c, Å
R, deg
â, deg
γ, deg
V, Å3
Z
96.64(1)
1625.3(9)
2
2
-1
w ) K[σ2(Fo) + gFo
]
was used; at convergence the K and g
D
calc, g cm-3
1.567
F(000)
760
values were 1.248 and 0.0003. Final R and Rw values were
0.0259 and 0.0299, respectively. The analytical scattering
factors, corrected for the real and imaginary parts of anoma-
lous dispersion, were taken from ref 34. All calculations were
carried out on the GOULD POWERNODE 6040 and ENCORE
91 computers of the “Centro di Studio per la Strutturistica
Diffrattometrica” del CNR, Parma, using the SHELX-76 and
SHELX-86 systems of crystallographic computer programs.35
cryst size, mm
µ(Mo KR), cm-1
θ range, deg
0.18 × 0.21 × 0.30
37.64
3-30
reflcns measd
(h,(k,l
unique tot. data
unique obsd data
R ) ∑|∆F|/∑|Fo|
Rw ) [∑w(∆F)2/∑w(Fo)2]1/2
9461
8219 [I > 2σ(I)]
0.0259
0.0299
Ack n ow led gm en t. This work was supported by the
DGICYT (Project PB93-0325) and E.C. (Human Capital
Mobility programme, Project ERBCHRXCT 940501).
L.Z. thanks the Spanish Ministerio de Educacio´n y
Ciencia for a grant.
mixture in 10 mL of dichloromethane and 70 mg (0.25 mmol)
of [NBu4]Cl was stirred at room temperature for 1 h. Evapo-
ration of the solvent to dryness gave a solid residue which was
purified by chromatography on alumina using toluene. Re-
moval of the solvent gave the complex 5b as a bright yellow
solid. Yield: 25%. 1H NMR (δ, CDCl3) 1.36 (m, 6H, 3 CH2),
1.65 (m, 2H, CH2), 2.06 (m, 2H, CH2), 2.47 (m), 2.81 (m, 4H,
P(CH2)2P), 7.28-7.67 (m, 20H, PPh2). 13C{1H} NMR (δ, CDCl3)
26.1 (s, CH2), 27.1 (m, P(CH2)2P), 27.4 (s, CH2), 28.1 (s, CH2),
30.8 (s, CH2), 35.8 (s, CH2), 128.3-135.8 (m, Câ, PPh2). MS
(FAB, m/e) [M+ - 2CO] ) 724, [M+ - Cl] ) 745. Anal. Calcd
for C36H35ClO2P2W: C, 55.37; H, 4.52. Found: C, 55.61; H,
4.88.
Cr ysta l Str u ctu r e Deter m in a tion of Com p lex 5a . Se-
lected crystallographic data for the complex 5a are listed in
Table 7. Data were collected at room temperature (22 °C) on
a Philips PW 1100 single-crystal diffractometer using graphite-
monochromated Mo KR radiation. All reflections with θ in the
range 3-30° were measured; of 9461 independent reflections,
8219, having I > 2σ(I), were considered observed and used in
the analysis. One standard reflection was monitored every
Su p p or tin g In for m a tion Ava ila ble: Fractional atom
coordinates (Table SI), hydrogen atom coordinates and isotro-
pic thermal parameters (Table SII), anisotropic thermal
parameters (Table SIII), and complete bond distances and
angles (Table SIV) (6 pages). Ordering information is given
on any current masthead page.
OM9601460
(33) (a) Walker, N.; Stuart, D. Acta Crystallogr., Sect. A 1983, 39,
158. (b) Ugozzoli, F. Comput. Chem. 1987, 11, 109.
(34) International Tables for X-ray Crystallography; Kynoch Press:
Birmingham, England, 1974; Vol. IV.
(35) Sheldrick, G. M. SHELX-76 program for crystal structure
determination, University of Cambridge, England, 1976; SHELXS-86
program for the solution of crystal structures, University of Go¨ttingen,
1986.