Expanding the tools available for direct ortho cupration – targeting lithium phosphidocuprates

Abstract

Reaction of in situ generated lithium phosphides with 0.5 eq. Cu(I) is employed as a means of targeting lithium phosphidocuprates of either Gilman- or Lipshutz-type formulation--e.g., (R(2)P)(2)CuLi·n(LiX) (n = 0, 1). For R = Ph, X = CN in toluene followed by thf or R = Ph, X = I in thf/toluene an unexpected product results. [(Ph(2)P)(6)Cu(4)][Li·4thf](2)1 reveals an ion-separated structure in the solid state, with solvated lithium cations countering the charge on an adamantyl dianion [(Ph(2)P)(6)Cu(4)](2-). Deployment of R = Ph, X = CN in thf affords a novel network based on the dimer of Ph(2)PCu(CN)Li·2thf 2 with trianions based on 6-membered (PCu)(3) rings acting as nodes in the supramolecular array and solvated alkali metal counter-ions completing the linkers. Cy(2)PLi (Cy = cyclohexyl) has been reacted with CuCN in thf/toluene to yield Gilman-type lithium bis(phosphido)cuprate (Cy(2)P)(2)CuLi·2thf 3 by the exclusion of in situ generated LiCN. A polymer is noted in the solid state.

Enhanced thermal stability of Cu–silylphosphido complexes via NHC ligation

“…Due to the potential reactivity and application of copper-phosphido complexes in organic and organometallic synthesis, a few homoleptic copper-PR 2 compounds have been prepared and structurally characterized. [18][19][20] In most of these complexes, the PR 2 groups act as a bridge between the copper centres and form cyclic structures such as [CuP t Bu 2 ] 4 . 19 On the other hand, different homoleptic metal-P(SiMe 3 ) 2 complexes have been reported with both terminal and bridging P(SiMe 3 ) 2 (metal = Zn, Cd, Hg, Sn, Pb, Mn), 1,2 among them [Cu 6 -{P(SiMe 3 ) 2 } 6 ] 1 by Buhro and co-workers.…”

Amidocuprates for Directed ortho Cupration: Structural Study, Mechanistic Investigation, and Chemical Requirements

“…Organocuprate(I) complexes are immensely valuable reagents for both industrial and research chemistry 1. During the past few decades, heteroleptic organocuprates bearing alkynyl,2a,b cyano,2c,d phenylthio,2e and phosphino2f,g groups have secured an important place in organic synthesis. Organo‐amidocuprates also represent an important class of heteroleptic cuprates in organic transformations, especially in stereoselective syntheses 3.…”

The first ring-expanded NHC–copper(i) phosphides as catalysts in the highly selective hydrophosphination of isocyanates

“…Despite this appeal, copper phosphides often form only as complex oligomers, with a concomitant reduction in reactivity. [8][9][10][11][12][13][14][15][16][17] Low-coordinate copper phosphides supported by sterically demanding ligands are far less common, as evidenced by the small number of structurally characterised (NHC)CuPR 2 (NHC = N-heterocyclic carbene) complexes hitherto reported. 18 Despite their relative rarity, such species hint at the potential of low-molecularity copper(I) phosphides.…”