First Asymmetric Synthesis of Passerini‐Type Condensation Products in Water Using Pregabalin: A Chiral Amino Acid for the Efficient Asymmetric Induction

Abstract

This article describes the use of Pregabalin as a commercially available chiral amino acid in the efficient synthesis of the Passerini‐type condensation products via two‐component condensation of aromatic aldehydes with cyclohexyl isocyanide. All reactions are accompanied with aerobic oxidation of aldehydes in water leading to chiral α‐acyloxycarboxamides with moderate to good enantioselectivities (up to 88 % ee) under green conditions such as nonmetal source. This is the first report of asymmetric synthesis of Passerini products in water.

Comparison of the effectiveness of two piperazine based nano-catalysts in the synthesis of benzoxazoles and benzimidazoles and use of the powerful one in the N-Boc protection of amines

“…Aer extensive studies on the introduction and application of various catalysts in our research group, [45][46][47][48][49][50][51] and especially the use of nano-catalysts such as piperazine immobilized on nano-ZnO-sulfuric acid (PINZS) and piperazinium nano silica sulfonate (PNSS) in the synthesis of some organic compounds, 52,53 in this research we decided to compare the catalytic properties of PINZS and PNSS in the synthesis of benzimidazole and benzoxazole derivatives. This research shows the importance of choosing of the appropriate support in the immobilization of ionic liquids.…”