The thermal treatment of 4-homoadamantanol and bicyclo[3.3.1]nonanols with hexamethylphosphorictriamide (HMPT) gave the corresponding olefins in moderate yields. The application of this dehydration method to a system in which olefin formation was regarded as difficult or impossible stereochemically led to various types of reactions, i.e., reduction, substitution, and phosphorodiamidation. Upon being
Aqueous organic two-phase reactions (halogen exchange, cyanation, and borohydride reduction) have been catalyzed by phosphoric triamides containing hydrophobic groups. The phosphoric triamides, which have a high cation binding ability, exibited high catalytic activity for the two-phase reactions. The catalytic activity of N-alkylteramethylphosphoric triamides (1) was higher than that of the corresponding pentamethyl derivatives and the difference has been explained in terms of the contribution of the dimeric species of 1 and/or hydrogen bonding between the NH of 1 and the anionic moieties of inorganic reagents.
The reactivity of five N-methyl N-benzyl phosphoramides with strong bases (RLi, R2NLi) depends on substituents at phosphorus. Metallation gives a carbanion which is not always stable and a novel elimination reaction is involved. A general scheme explains the experimental data. Alkylation and condensation reactions on various substracts (halides, ketones, aldehydes, imines, epoxides), and a new direct
N-benzylpentamethylphosphoramide, can be used as phase-transfer catalysts in two-phase reactions. Polymeric phosphoramides, which were prepared by the copolymerization of N-(p-vinylbenzyl)pentamethylphosphoramide with styrene, were found to catalyze phase-transfer reactions more efficiently than their monomeric analogs.