Platinum-Catalyzed Enantioselective Tandem Alkylation/Arylation of Primary Phosphines. Asymmetric Synthesis of P-Stereogenic 1-Phosphaacenaphthenes

Abstract

Enantioselective tandem alkylation/arylation of primary phosphines with 1-bromo-8-chloromethylnaphthalene catalyzed by Pt(DuPhos) complexes gave P-stereogenic 1-phosphaacenaphthenes (AcePhos) in up to 74% ee. Diastereoselective formation of four P-C bonds in one pot with bis(primary) phosphines gave C2-symmetric diphosphines, including the o-phenylene derivative DuAcePhos, for which the rac isomer was formed with high enantioselectivity. These reactions, which appear to proceed via an unusual metal-mediated nucleophilic aromatic substitution pathway, yield a new class of heterocycles with potential applications in asymmetric catalysis.

Preparation of phosphines through C–P bond formation

“…As expected, a mechanistic study suggested that the major enantiomer of product was formed from the major diastereomer of the platinum–phosphido intermediate [63]. Glueck and co-workers also developed an analogous method for the tandem alkylation/arylation of primary phosphines on the basis of a platinum catalyst resulting in several enantio-enriched phosphaacenaphtalenes [64]. …”

Synthesis of ligands based on naphthalene peri-substituted by Group 15 and 16 elements and their coordination chemistry

“…Ligands possessing phosphorus and carbon atoms in the peripositions of the naphthalene ring generally act as monodentate via phosphorus [64,65]. An exception to this is an organometallic species 90, which is obtained by the elimination of methane on coordination of [CoMe(PMe 3 ) 4 ] to 89 (Scheme 39) [66].…”

Synthesis and use of borane and platinum(II) complexes of 3‐diphenylphosphino‐1‐ phenylphospholane (LuPhos)

“…In this series, only DuPhos has been applied in platinum complexes [18][19][20]. 3-Diphenylphosphino-1-phenyl-1,2,3,6-tetrahydrophosphinine and its 1,2,3,4,5,6-hexahydrophosphinine derivative were also described as novel bidentate P-ligands in Pt(II) complexes [21][22][23][24][25][26] showing unusual regioselectivity as catalysts in the hydroformylation of styrene [27].…”