Reactivity of electrophilic terminal phosphinidene complexes toward phosphorus ylides

Article abstract of DOI:10.1016/S0022-328X(02)01146-4

Stabilised phosphorus ylides react with transient terminal phosphinidene complexes [RP-W(CO)5] (R=Ph, Me) to give products resulting from a formal insertion of P into a C-H bond via an initial nucleophilic attack of the ylidic carbon.

Full text of DOI:10.1016/S0022-328X(02)01146-4

Journal of Organometallic Chemistry 650 (2002) 57–58
www.elsevier.com/locate/jorganchem
Reactivity of electrophilic terminal phosphinidene complexes
toward phosphorus ylides
Ngoc Hoa Tran Huy *, Carine Compain, Louis Ricard, Franc¸ois Mathey *
Laboratoire ‘He´te´roe´le´ments et Coordination’ UMR CNRS 7653, DCPH, Ecole Polytechnique, 91128 Palaiseau Cedex, France
Received 7 December 2001; accepted 17 December 2001
Abstract
Stabilised phosphorus ylides react with transient terminal phosphinidene complexes [RPꢀW(CO)5] (R=Ph, Me) to give
products resulting from a formal insertion of P into a CꢀH bond via an initial nucleophilic attack of the ylidic carbon. © 2002
Elsevier Science B.V. All rights reserved.
Keywords: Phosphorus ylides; Phosphinidenes; Transition metals
data can be compared with those of the starting ylide:
l −1.86 and JCP=134.8 Hz [5]. The formation of 1
can be simply explained by a nucleophilic attack of the
ylidic carbon at the phosphinidene phosphorus, fol-
lowed by a proton transfer (Eq. (1)).
The versatile carbene-like chemistry of transient ter-
minal phosphinidene–pentacarbonylmetal complexes
[RPꢀM(CO)5] (M=Cr, Mo, W) is currently under ac-
tive investigation [1]. These species display an elec-
trophilic behaviour, and their reactions with a series of
oxygen, nitrogen and phosphorus nucleophiles have
been studied in some depth. In most cases, the forma-
tion of transient or stable ylidic adducts has been
demonstrated [2]. To the best of our knowledge, how-
ever, nothing is known about their reactivity toward
carbon nucleophiles. It is clear that highly nucleophilic
species, such as organolithium compounds, cannot give
clean reactions with [RPꢀM(CO)5] since side-attacks at
the carbonyl groups are expected at both the phos-
phinidene complexes and their 7-phosphanorbornadi-
ene precursors [3]. Against such a background, we
decided to investigate the reactivity of [RPꢀW(CO)5]
(R=Ph, Me) toward a representative selection of phos-
phorus ylides chosen as typical mild carbon nucle-
ophiles. The phosphinidene complexes were generated
from the appropriate 7-phosphanorbornadiene precur-
sors [3]. It soon appeared that only stabilised ylides
gave reproducible and clear-cut results.
1
(1)
The result of the reaction with Ph3PꢁCHCO2Et is
more unexpected. Complex 2 was unambiguously char-
acterised by NMR and mass spectrometry [6]. An
equimolar amount of [Ph3PꢀW(CO)5] was also isolated
and characterised by 31P-NMR and mass spectrometry
(Eq. (2)). The mechanism of the reaction leading to 2 is
presently unclear.
(2)
With cyclopentadienylidenephosphoranes, the reac-
tion is similar to the first case. The insertion of phos-
phinidene takes place at the b-carbon of the ring,
probably for steric reasons, leading to complexes 3 and
4 [7] (Eq. (3)).
The reaction with Ph3PꢁCHCN leads to a new ylide
1 [4], whose ylidic carbon resonates at 9.55 (CDCl3)
1
with J couplings of 106.6 (Ph3P) and 47.7 Hz. These
* Corresponding authors. Tel.: +33-1-69-33-4079; fax: +33-1-69-
33-3029.
(3)
E-mail address: mathey@poly.polytechnique.fr (F. Mathey).
0022-328X/02/$ - see front matter © 2002 Elsevier Science B.V. All rights reserved.
PII: S0022-328X(02)01146-4

58
N.H. Tran Huy et al. / Journal of Organometallic Chemistry 650 (2002) 57–58
Phosphorus: The Carbon Copy, Wiley, Chichester, 1998, p. 19;
(b) K. Lammertsma, M.J.M. Vlaar, Eur. J. Org. Chem. (2002), in
press;
(c) F. Mathey, N.H. Tran Huy, A. Marinetti, Helv. Chim. Acta
84 (2001) 2938.
[2] Typical examples: (a) P: P. Le Floch, A. Marinetti, L. Ricard, F.
Mathey, J. Am. Chem. Soc. 112 (1990) 2407;
(b) N: R. Streubel, U. Schiemann, P.G. Jones, N.H. Tran Huy, F.
Mathey, Angew. Chem. Int. Ed. Engl. 39 (2000) 3686;
(c) O: Y. Inubushi, N.H. Tran Huy, L. Ricard, F. Mathey, J.
Organomet. Chem. 533 (1997) 83;
(d) R. Streubel, A. Ostrowski, H. Wilkens, F. Ruthe, J. Jeske, P.J.
Jones, Angew. Chem. Int. Ed. Engl. 36 (1997) 378.
[3] A. Marinetti, F. Mathey, J. Fischer, A. Mitschler, J. Chem. Soc.
Chem. Commun. (1982) 667.
[4] 1: purified by chromatography on silica gel with CH2Cl2–Et2O,
2
1
10:1. 31P-NMR (CDCl3): l −31.08 (HPW), JPP 11.6 Hz, JPH
354.4 Hz, JPW 231.8 Hz; 23.4 (Ph3P); 1H-NMR (CDCl3): l 5.80
1
,
Fig. 1. Crystal structure of 4. Significant bond distances (A) and
angles (°): P(1)ꢀC(1), 1.796(4); P(1)ꢀC(2), 1.793(3); P(1)ꢀW(1),
2.530(1); C(2)ꢀC(3), 1.416(4); C(3)ꢀC(4), 1.376(4); C(4)ꢀC(5),
1.417(4); C(5)ꢀC(6), 1.431(4); C(6)ꢀC(2), 1.395(4); P(2)ꢀC(5),
1.731(3); P(2)ꢀC(7), 1.803(3); P(2)ꢀC(13), 1.794(3); P(2)ꢀC(19),
1.811(3). C(2)ꢀP(1)ꢀW(1), 120.2(1); C(2)ꢀP(1)ꢀC(1), 104.1(2);
C(1)ꢀP(1)ꢀW(1), 117.2(2); C(4)ꢀC(5)ꢀC(6), 107.6(3); C(4)ꢀC(5)ꢀP(2),
124.8(2); C(6)ꢀC(5)ꢀP(2), 127.5(2); C(5)ꢀP(2)ꢀC(7), 114.6(1);
C(5)ꢀP(2)ꢀC(13), 109.3(1); C(5)ꢀP(2)ꢀC(19), 111.6(1).
(dd, 1JHP=354.7 Hz, 3JHP=6.9 Hz, PH); 13C-NMR (CDCl3): l
9.55 (dd, 1JCP=106.6 and 47.4 Hz, CP2), 126.99 (dd, 2JCP=17.5
and 8.4 Hz, CN), 197.37 (d, 2JCP=6.5 Hz, cis-CO), 201.11 (d,
2JCP=21.3 Hz, trans-CO); EIMS (184W); m/z: 707 ([M+−CO+
2H], 2.6%), 651 ([M+−3CO+2H], 16.9%), 594 ([M+−5CO+
H], 13%), 300 (Ph3PCCN, 100%), 262 (Ph3P, 84%).
[5] For a discussion on the 13C-NMR data of phosphorus ylides, see:
A.W. Johnson, Ylides and Imines of Phosphorus, Wiley, New
York, 1993, p. 55.
[6] [Ph3PꢀW(CO)5] was first recovered by chromatography with hex-
ane–CH2Cl2, 4:1, then 2 with hexane–CH2Cl2, 1:2. 31P-NMR
(CDCl3): l 114.1, JPW=286.8 Hz; H-NMR (CDCl3): l 1.05 (m,
CH3), 1.32 (m, CH3), 3.35 (m, PꢀCH2), 3.86 (m, OCH2), 3.98 (m,
OCH2), 7.43 (m, Ph); 13C-NMR (CDCl3): l 14.50 (s, Me), 16.75
1
1
Complex 4 has been characterised by X-ray crystal
structure analysis [8]. The structural data (Fig. 1) indi-
cate that the ylidic carbon is planar (ꢀangles=359.9°)
3
1
(d, JCP=8.7 Hz, Me(PꢀOEt)), 45.53 (d, JCP=12.2 Hz, PꢀCH2),
,
and that the P(2)ꢀC(5) bond at 1.731(3) A is in the
2
62.10 (s, CO2CH2), 64.63 (d, JCP=4.3 Hz, PꢀOꢀCH2), 167.64 (s,
normal range for a cyclopentadienylide [9]. Finally, the
reaction of electrophilic terminal phosphinidene com-
plexes with stabilised phosphorus ylides appears to be a
relatively versatile method for synthesising PꢀC bonds.
CO2), 196.71 (d, 2JCP=7.9 Hz, cis-CO), 199.52 (d, 2JCP=26.7
Hz, trans-CO); MS; m/z: 537 ([M+−CO+H], 50%), 425 ([M+
−5CO+H], 75%), 382 (100%).
[7] 3: purified by chromatography with hexane–CH2Cl2, 1:3. 31P-
NMR (CDCl3): l −40.7 (PꢀW), 1JPW=220 Hz, 14.0 (Ph3P);
1H-NMR (CDCl3): l 6.28, 6.33 and 6.66 (3m, Cp), 6.75 (d,
1JHP=340.5 Hz, PH); 13C-NMR (CDCl3): l 84.88 (dd, JCP
=
1
1. Supplementary material
110.6 Hz, 3JCP=15.9 Hz, PꢁC); MS; m/z: 760 ([M++2], 1.6%),
704 ([M++2−2CO], 63%), 262 (Ph3P, 100%). 4 purified by
chromatography with hexane–CH2Cl2, 1:3. 31P-NMR (CDCl3): l
−71.9 (PꢀW), 1JPW=220.4 Hz, 13.6 (Ph3P); 1H-NMR (CDCl3):
Crystallographic data for the structural analysis have
been deposited with the Cambridge Crystallographic
Data Centre, CCDC no. 175168 for compound 4.
Copies of this information may be obtained free of
charge from The Director, CCDC, 12 Union Road,
Cambridge CB2 1EZ, UK (Fax: +44-1223-336033;
e-mail: deposit@ccdc.cam.ac.uk or www: http://
www.ccdc.cam.ac.uk).
1
l 5.98 (dd, JHP=332 Hz, PH), 6.28 and 6.47 (m, Cp); 13C-NMR
(CDCl3): l 84.53 (dd, 1JCP=110.9 Hz, 3JCP=15.3 Hz, PꢁC); MS;
m/z: 698 ([M++2], 6.3%), 642 ([M++2−2CO], 100%), 262
(Ph3P, 75%). Ph3PꢁCp: for comparison, 13C-NMR (CDCl3): l
79.63 (d, 1JCP=113.2 Hz, CꢁP).
[8] Crystal data for 4 C29H22O5P2W, M=696.26 g mol−1, triclinic,
,
,
,
a=10.619(5) A, b=11.423(5) A, c=12.628(5) A, h=65.710(5)°,
3
,
i=79.290(5)°, k=80.010(5)°, V=1363.8(10) A , T=150.0(1) K,
space group P-1, Z=2, v(Mo–Ka)=4.389 cm−1, 10 933 reflec-
tions measured, 7864 unique (Rint=0.0290), which were used in
all calculations. The final wR(F2) was 0.0730, R1=0.0322 (all
data).
References
[9] See Ref. [5], p. 48.
[1] For recent reviews, see: (a) K.B. Dillon, F. Mathey, J.F. Nixon,