Rearrangement of chloromethylphosphinidene into methylenechlorophosphine in the co-ordination sphere of tungsten. Stabilization of an unhindered PC double bond without deactivation by π-complexation

Abstract

Transient [CICH2-P=W(C0)5] rearranges into stable (q2-CH2=PCl)W(CO), which can be characterized in solution by i.r., 1H n.m.r., and 31P n.m.r. spectroscopy and reacts readily with alcohols and conjugated dienes as a a-P-co-ordinated species.

Metal-Assisted Cycloaddition Reactions in Organotransition Metal Chemistry

“…540 The cycloadducts of 96 (M ) Cr, W; X ) S, Se; R ) H) with cyclopentadiene have exo/endo ratios of e7. at 55°C in the presence of CuCl, it rearranged 74,543 into stable (η 2 -CH 2 dPCl)W(CO) 5 (313), which could be characterized spectroscopically in solution. The η 2 -coordination of the PdC double bond, which was unequivocally established through the spectroscopic results, obviously very effectively stabilizes the molecule.…”

“…Likewise, CpMo(CO) 3 (η 1 -2,4-pentadien-1-yl) cycloadds the dienophiles TCNE and maleic anhydride in DielsAlder fashion to give a single stereoisomer of 340 and 341, respectively. 577 Clearly related to the reactions of η 1 -Cp complexes (vide supra) are the metal assisted [4+2] cycloaddition reactions of metal bound silole 578 (Scheme 48), and phosphole 74,515,516,579 (e.g., 343 in eq 90, cf. also 285 in eq 80), giving, e.g., complexes 342 and 344.…”

“…69 Phosphinidene transfer reactions have been reported by Mathey et al (eq 11). [70][71][72][73][74][75][76][77] Terminal phosphinidene complexes 14, RPdM(CO) 5 (M ) Cr, Mo, W) were generated in situ from 7-phosphanorbornadiene complexes 13 (cf. sections II.D.1 and II.D.2) at 55°C with CuCl as catalyst.…”

Phospha‐ and Arsaalkenes RE=C(NMe2)2 (E = P, As) as Novel Phosphinidene‐ and Arsinidene‐Transfer Reagents

“…Functionalized phosphinidene complexes are frequently involved in interesting intramolecular rearrangement processes, which impressively underline the great versatility of the Psubstituents [30,[37][38][39] (Scheme 28). Another type of intramolecular addition of a coordinated phosphinidene was realized by heating complex 68a in tolu- ene at 80°C to give the diphosphane basket 69a as the sole isolable product in 66 % yield.…”

“…The reaction of equimolar amounts of tBuP=C(NMe 2 ) 2 (82a) and copper(I) chloride afforded the complex [Cu 3 Cl 3 {µ 3 -P(tBu)C(NMe 2 ) 2 } 3 ] (87) as the formal result of the cyclotrimerization of a 1:1 adduct (76 % yield). [61] Analogously, complex 88 was synthesized in 66 % yield from phosphaalkene PhP=C(NMe 2 ) 2 (82d) and [Cu{P(OMe) 3 } 3 Cl] [38] (Scheme 39). Similarly, the analogous complexes [Cu 3 X 3 {µ-P(tBu)C(NMe 2 ) 2 } 3 ] (X = Br, I) were generated.…”