SYNTHESIS OF POLYPODAL DIPHENYLPHOSPHINE LIGANDS. A REVIEW

Recent Applications of Chiral Ferrocene Ligands in Asymmetric Catalysis

Despite the impressive progress achieved in asymmetric catalysis during the last decade, an increasing number of new catalysts, ligands, and applications are reported every year to satisfy the need to embrace a wider range of reactions and to improve the efficiency of existing processes. Because of their availability, unique stereochemical aspects, and wide variety of coordination modes and possibilities for the fine-tuning of the steric and electronic properties, ferrocene-based ligands constitute one of the most versatile ligand architectures in the current scenario of asymmetric catalysis. Over the last few years ferrocene catalysts have been successfully applied in an amazing variety of enantioselective processes. This Review documents these recent advances, with special emphasis on the most innovative asymmetric processes and the development of novel, efficient types of ferrocene ligands.

Alkylation of phosphine boranes by phase-transfer catalysis

The alkylation of phosphine boranes with various electrophiles proceeds with good to excellent yields in a biphasic solution in the presence of tetrabutylammonium bromide as a phase-transfer catalyst. [reaction: see text]