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A series of chiral enantiopure phosphinites was synthesized in four steps starting from phosphinic acid. New species were obtained as alkoxyphosphonium compounds. They can be used in the asymmetric hydrogenation of functionalized alkenes.

Enantioselective syntheses O 00311-Alkoxy-2,5-diphenylphospholane and -phospholanium Salts in Rhodium-Catalyzed Asymmetric Hydrogenation. -Phosphinites (I), their phosphonium salts (II) and their rhodium complexes (III) are prepared in a few steps and examined in the asymmetric hydrogenation of alkenylamine (IV) and cinnamate (VI). Complex (IIIb) affords the best enantioselectivity (75% e.e.) at quantitative conversion of the cinnamate. The enantioselectivities obtained with the other ligands or preformed complexes are only moderate and similar for either the phosphinite, the salt or the preformed complex. -(GALLAND, A.; PARIS, J. M.; SCHLAMA, T.; GUILLOT, R.; FIAUD, J.-C.; TOFFANO*, M.; Eur.