Syntheses and properties of novel polyphosphines containing various combinations of primary, secondary, and tertiary phosphorus atoms

Abstract

Novel polyphosphines can be prepared by the base-catalysed addition of R, P-H across the carbon-carbon double bonds of vinylphosphonate esters, followed by reduction with lithium aluminium hydride. Thus a tertiary-primary diphosphine, a tertiary-diprimary triphosphine, a tertiary-triprimary tripod tetraphosphine, and a ditertiary-diprimary linear tetraphosphine have been prepared. Similarly, the tertiary-secondary diphosphine Ph,P*CH,-CH,*PH Ph can be prepared by base-catalysed addition of diphenylphosphine to isopropyl phenylvinylphosphinate followed by reduction. The secondary-primary diphosphine PhPH*CH,*CH,*PH, can be prepared by the Arbusov reaction of di-isopropoxy(pheny1)phosphine with di-isopropyl 2-bromoethylphosphonate followed by reduction. The i.r., l H n.m.r., sl P n.m.r.. and mass spectra of the new compounds are discussed.

Iron(0) and ruthenium(0) complexes with tridentate phosphonite ligands and their potential for ketene formation from methyl iodide, CO and a base

“…The tridentate phosphine ligands RP[CH 2 -CH 2 P(OMe) 2 ] 2 (R = Me, Ph), prepared from alcoholysis of aminophosphine intermediates, have been reported by King and Masler [7]. The procedure involves a base catalysed addition [2,3,16,17,7] of dimethylvinylphosphonite to methyl-or phenylphosphine. The required vinyl phosphonite intermediate was obtained from the reaction of bis(dimethylamino)vinylphosphine with methanol.…”

Tridentate phosphine ligands bearing aza-crown ether lariats

“…The overall objective is to design a scalable and modular synthesis of these frameworks so that we could systematically investigate the impacts of substituents and linker length on alkali metal-substrate interactions in TM complexes. To that end, we initially focused on using primary phosphine synthons and rely on addition of the P-H bonds across the C=C bonds in vinylphosphines and vinylphosphonates [32,33]. We investigated both radical-initiated and anion-catalyzed variations of these reactions.…”

Phosphane and Bis(phosphane) Ligands from Phosphinic Acids

“…Although base-catalyzed additions of primary [16] or secondary [17] phosphanes to functionally activated olefins is extensively described, we encountered some difficulties while treating phosphanes 7؊9 with diethyl(vinyl)phosphonate in the presence of catalytic amounts of EtONa in ethanol, since the resulting phosphaneϪphosphonates were contaminated with significant quantities (up to 20%) of phosphoniumϪbis(phosphonates), resulting from a second addition to the vinylphosphonate, probably owing to the basic character of the phosphanes. With EtONa in THF, reaction times were exceedingly long.…”