One-Pot Four-Component Synthesis of Novel Amino-Tetrahydro-Chromene Derivatives Anchored with Dual Triazole Moieties

A double aldol condensation-Michael addition-cyclization-double click reaction sequence is conducted in one pot for the synthesis of a novel series of tetrahydro-chromene derivatives anchored with dual triazole rings. The process is optimized primarily step by step under ultrasonic irradiation in a basic aqueous t-BuOH medium. The steps are then successfully combined into a four-component one-pot reaction using the optimum conditions, where the whole operation took less than 2 h to complete. As a result, the new products are precipitated in the reaction vessel and obtained directly by simple filtration-crystallization without undergoing any other costly separation or chromatographic operations. The structures of the intermediates and the products are characterized using various spectroscopic methods.