Vitamin-catalyzed organic transformations: a green synthetic tool inspired by nature

Vitamins are not only essential for normal cell function but also important in organic transformations, specifically in the field of organocatalysis. Due to the increasing importance of sustainable and ecofriendly organic reaction protocols, there has been growing attention in organocatalysis owing to easy access, biocompatibility, and excellent reactivity. As vitamins are environmentally benign, nontoxic, and economic organocatalyst, VB₁, VB₂, and VB₁₂ have been employed successfully in variety of organic transformations. The catalysts exhibited very high efficacy in various C–C bond-forming reactions from multicomponent reaction to cross-coupling reactions. This review concisely demonstrates catalytic performance of natural organocatalyst VB₁, VB₂, and VB₁₂ and also provides basic knowledge about this important synthetic tool for the preparation of organic compounds in a greener manner. The review explores the versatile application of vitamins where vitamins acted as the principal catalyst (Lewis acidic catalyst, photocatalyst), co-catalyst, organometallic catalyst, and ligand of metal ion catalysts. Utilization of vitamin-functionalized nanocatalysts in cross-coupling, A³-coupling, oxidation reaction, etc. has been demonstrated thoroughly. Additionally, the mechanistic details illuminating the roles of vitamins in important organic transformations are meticulously explained, providing insights into reaction pathways and empowering the described organcatalysis approaches.