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A general and efficient rhodium‐catalyzed asymmetric cyanide‐free hydrocyanation of alkenes has been developed. Based on the asymmetric hydroformylation/condensation/aza‐Cope elimination sequences, a broad scope of substrates including mono‐substituted, 1,2‐, and 1,1‐disubstituted alkenes (involving natural product R‐ and S‐limonene) were employed, and a series of valuable chiral nitriles are prepared with high yields (up to 95 %) and enantioselectivities (up to 98 % ee). Notably, the critical factor to achieve high enantioseletivies is the addition of catalytic amount of benzoic acid. This novel methodology provides an efficient and concise synthetic route to the intermediate of vildagliptin and anagliptin. [ABSTRACT FROM AUTHOR]

Excellent enantioselectivities (up to 97 % ee) and diastereoselectivities (up to >99:1 d.r.) have been achieved in the desymmetrization of cyclopentenes by catalytic hydroformylation. This novel methodology provides an efficient and concise synthetic route to chiral cyclopentane carboxaldehydes. The key intermediate, (1 S,3 S)-(3-hydroxymethyl)cyclopentanol, for the synthesis of carbocyclic-ddA was obtained in three steps. [ABSTRACT FROM AUTHOR]

Highlights from the article: Keywords: Asymmetrische Synthese; Hydrocyanierung; Hydroformylierung; Nitrile; Rhodium Auf Basis einer Sequenz aus asymmetrischer Hydroformylierung, Kondensation und Aza-Cope-Eliminierung wurden vielfältige Substrate, z. B. monosubstituierte sowie 1,2- und 1,1-disubstituierte Alkene, eingesetzt, um eine Reihe nützlicher chiraler Nitrile in hohen Ausbeuten von bis zu 95 % und mit Enantioselektivitäten von bis zu 98 % ee herzustellen. Asymmetrische Synthese, Hydrocyanierung, Hydroformylierung, Nitrile, Rhodium.