Phosphine-catalyzed tandem Michael addition/intramolecular Wittig reactions have been developed for the synthesis of chiral 2,5-dihydro-1H-pyrrole and tetrahydropyridine derivatives. These processes rendered catalytic in phosphine, thanks to situ reduction phosphine oxide by phenylsilane. Furthermore, asymmetric P(III)/P(V) were implemented using enantiopure phosphines.

The synthesis and structural characterization of a series of tripodal tris(phosphine) ligands, containing SiMe2 elbow groups, is described. The significant steric congestion in these ligands, due to the silylmethyl substituents, is manifest both in the solid-state structures and in the solution NMR spectra of the free ligands. Variable temperature 1H{31P} NMR studies of one of the ligands, CH3C...

The utilization of phosphirenium ions is presented; optimized and broadened three-membered ring construction described together with the use these as efficient pre-catalysts for metal-free carbonyl reduction silanes. Full characterization presented, initial experimental computational mechanistic studies indicate that act a “masked phosphenium” source accessed via opening. Catalysis proceeds ass...

Catalytic synthesis of nonracemic P-chiral phosphine derivatives remains a significant challenge. Here we report Cu-catalyzed enantioselective arylation of secondary phosphine oxides with diaryliodonium salts for the synthesis of tertiary phosphine oxides with high enantiomeric excess. The new process is demonstrated on a wide range of substrates and leads to products that are well-established ...

U.S. exported lettuce, broccoli, asparagus, and strawberries oftenharborwesternßower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), a quarantined pest in Taiwan, and therefore require quarantine treatment. Fumigation with diluted pure phosphine at a low temperatureof 2 Cwas studied to controlwesternßower thrips and todetermineeffects on thequality of the treated produc...

Gas-chromatographic analysis of the volatile compounds in the headspace of cultures inoculated with sewage sludge indicated phosphine production over a period of several days, a reaction which is clearly microbiologically mediated. The amounts of phosphine recovered from 40-mL specimens sewage sludge enrichment were in a pg-range of 5 to 100 in the presence of glucose as carbon source and phosp...

A series of substituted benzoyl radicals has been generated by laser flash photolysis of alpha-hydroxy ketones, alpha-amino ketones, and acyl and bis(acyl)phosphine oxides, all of which are used commercially as photoinitiators in free radical polymerizations. The benzoyl radicals have been studied by fast time-resolved infrared spectroscopy. The absolute rate constants for their reaction with n...