Complexes with functional phosphines. 13. Reactivity of coordinated phosphino enolates and metallacycles toward chlorophosphines with diastereoselective formation of P-O and P-C bonds. Alkaline hydrolysis of coordinated phosphinites leading to oxodiarylphosphoranido ligands. Synthesis and molecular structure of cis-[Pd[Ph2PCH=C(O)Ph][PhP(O)(CH2C9H6N)]]

Abstract

Chlorodiphenylphosphine reacts with m-[MjPh2PCH=C(0)Phj2] (M = Ni (1), Pd (2), Pt (3)) to afford the complexes cis-[MCl2jPh2PCH=C(Ph)OPPh2j] (4-6, respectively), resulting from selective coupling of the oxygen atom of the enolate with phosphorus. Phosphorus double functionalization is achieved in the reaction of dichlorophenylphosphine with [(C N)Pd-(Ph2PCH=C(6)Phj] (CN = o-C6H"CH2NMe2 (7), C10H8N (8)) in the presence of pyridine, affording m-[PdCl2-|Ph2PCH=C(Ph)OP(Ph)(o-C6H4CH2NHMe2)!]Cl ( 9) and m-[PdCl2|Ph2PCH=C(Ph)OP(Ph)(CH2C9H6NH)|]Cl (10), respectively. These constitute the first examples of coupling reactions between a phosphorus atom and a transition-metal-bound carbon atom of a cyclometalated ligand. The new P P~N ligands are formed in a diastereoselective reaction and behave as P,P chelates to palladium. Compounds 9 and 10 are readily hydrolyzed in alkaline solutions, affording the oxodiarylphosphoranido complexes m-[Pd(Ph2PCH=C(0)Ph|(PhP(0)(o-C6H4CH2NMe2)|] (11) and rii-[Pd¡Ph2PCH==C(0)Ph|{PhP(0)-(CH2C9H6N)j] ( 12), respectively. The molecular structure of 12-CHC13 has been determined by X-ray diffraction: triclinic, space group , with Z = 2,a= 10.749 (5) A, b = 12.285 (3) A, c = 14.022 (5) A, a = 70.61 (2)°, ß = 86.80 (3)°, y = 81.54 (3)°, and V = 1727.8 A3. The structure has been refined for the 2612 reflections with F02 5> 3a(Ff) to R = 0.057 and Rw = 0.067.The coordination of the palladium deviates from the ideal planar geometry mainly because of the lack of flexibility of the P,N chelate, which prevents the nitrogen atom from occupying a position in the coordination plane. This also leads to a somewhat elongated Pd-N bond (Pd-N = 2.207 (7) A). All complexes were characterized by elemental analysis, IR spectroscopy, and and 31P('H) NMR spectroscopy.

Monocyclopentadienyl complexes of niobium, tantalum and tungsten containing heterodifunctional P,O ligandsDedicated to Prof. P. Royo on the occasion of his 65th birthday, with our warmest congratulations.

“…82 The Cp cent -M-P(1) angles range from 175.76 (6a) to 178.48 (6d) and are slightly more obtuse than those found in the ylide complex [(Z-C 5 Me 5 )TaCl 4 (CH 2 =PMePh 2 )] (173 ) 83 or in [(Z-C 5 H 5 )NbCl 4 (PMePh 2 )] (174.6 ), 76 bond angles which are consistent with those reported for related structures. 76,[83][84][85] The M-O(1) bond lengths are similar to those found in other transition metal complexes with the same phosphino-enolate ligand [35][36][37][38][39]41,[43][44][45][46]49 87 The other bond lengths and angles of the phosphino-enolate and cyclopentadienyl ligands are within the expected range.…”

“…Anionic phosphino-enolates, formed from ketophosphines, are also a well-developed group of P,O ligands. [34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49] Interest in this chemistry partly stems from the fact that nickel phosphino-enolate complexes catalyze the oligomerisation of ethylene in a-olefins (Shell Higher Olefin Process). 34,40,50,51 Substitutional modification of the phosphino-enolate ligands can modify catalyst activity and the chain length distribution.…”

“…[49][50][51][52] Numerous phosphino-enolate complexes of group 8-10 metals have been synthesized and their reactivity studied. [35][36][37][38][39][41][42][43][44][45][46]49,[53][54][55][56][57][58] For example, Rh(I) complexes in this class are efficient catalysts for the transfer dehydrogenation of alkanes to alkenes. 59 As for their neutral counterparts, the early transition metal chemitry of anionic P,O ligands has been little investigated.…”

Influence of the Flexibility of Nickel PCP‐Pincer Complexes on C−H and P−C Bond Activation and Ethylene Reactivity: A Combined Experimental and Theoretical Investigation

“…[81] The Ni1À P1 bond length of 2.2019(5) Å is also indicative of the trans influence of the aryl ligand at C16. It is interesting to recall that reactions related to a "reverse" of the PÀ C bond breaking reaction leading to 15 were observed (i) in Ni II phosphinite/phosphane complexes, [82] (ii) when metallacyclic Pd II complexes containing C,P and P,O chelates were reacted with PPhCl 2 with formation of CÀ P and OÀ P bonds, [83,84] and in Pt cluster chemistry with the reductive coupling of a bridging μ-PPh 2 group with a cis-phenyl ligand to form a PPh 3 ligand. [85] Note, however, that in cases (i) and (ii), the PR 2 group does not originate from a phosphanido ligand.…”

Synthesis of chelate complexes and the dichalcogen derivatives of the unsymmetrical diphosphine ligand Ph2PNHC6H4PPh2. Molecular structure of [PtCl2(Ph2PNHC6H4PPh2)]·0.75dmso·0.75CHCl3

“…In comparison there are relatively few examples in the chemical literature of unsymmetrical, potentially bidentate bisphosphines containing P-C-C-X-P backbones, where X = C, 1,2 Si, 3,4 O, 5-11 or S, 12 fewer still where X = N, [13][14][15] and no examples, to the best of our knowledge, where transition metal complexes have been prepared using preformed P-C-C-N-P backboned ligands. Six-membered P-C-C-O-P-M metallacycles (where M = Pd 16, 17 and Pt 17 ) and platinum() and palladium() P-C-C-N-P-M metallacycles have previously been reported 18 19 a series of Group 10 metallacycles formed by reaction of Ph 2 PCl or PhPCl 2 with phosphino-enolate complexes [20][21][22] and the elimination/rearrangement reaction of a palladium complex bearing a phosphino-hydroquinone ligand in an acidic medium 23 We recently described the synthesis of Ph 2 PNHC 6 H 4 PPh 2 an unsymmetrical diphosphine derived from 2-(diphenylphosphino)aniline 25 and have shown that the difference in basicity or the steric properties of the two different phosphorus atoms of Ph chloride-bridged dimers in thf leads to monometallic species in which the diphosphine ligand binds to the metal only via the amino-phosphine moiety. Subsequent dissolution of these complexes in other solvents e.g.…”