Water-Mediated Strecker Reaction: An Efficient and Environmentally Friendly Approach for the Synthesis of α-Aminonitriles via a Three-Component Condensation

Organocatalytic Synthesis of α-Aminonitriles: A Review

α-Aminonitriles, which have anticancer, antibacterial, antiviral, and antifungal properties, have played an important role in pharmacology. Furthermore, they can also be used to synthesize natural and unnatural amino acids. The main bottleneck in the commercialization of these products is their large-scale production with controlled chirality. A variety of methods have been used to synthesize α-aminonitriles. Among other reported methods for preparing α-aminonitriles, the Strecker reaction is considered appropriate. Recent developments, however, have enabled the α-cyanation of tertiary and secondary amines by functionalizing the carbon–hydrogen (C–H) bond as an attractive alternative procedure for the preparation of α-aminonitriles in the presence of an oxidant and a cyanide source. In most cases, these reactions are catalyzed by transition metal catalysts, such as Fe, Cu, Rh, V, Au, Ru, Mo, Pt, Re, and Co, or by photocatalysts. As an alternative, organocatalysts can also be used to produce aminonitriles. Although there have been numerous reviews on the preparation of α-aminonitriles, no such reviews have been published specifically on the organocatalyzed synthesis of α-aminonitriles. Organocatalysis plays a significant role in synthesizing α-aminonitriles via Strecker-type reactions and cross dehydrogenative coupling reactions (CDC). In this mini review, we discuss the organocatalyzed synthesis of these molecules. A review of new organocatalysts for the synthesis of aminonitriles is expected to provide insight into the development of new industrial catalysts.

pH-controlled regioselective nucleophilic ring-opening of epoxide: an improved process for the preparation of (R)-(-)- or (S)-(+)-3-hydroxytetrahydrofuran

An environmentally benign, cost-effective and scalable process for the preparation of both the enantiomers of 3-hydroxytetrahydrofuran has been developed. pH-Controlled ring opening of enantiomerically pure epichlorohydrins with cyanohydrin is the key step of the process. The entire protocol does not require any column purification.