1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU)-Promoted Nucleophilic Addition of Two Molecules of Nitroalkanes to Diazo Compounds: Synthesis of Highly Functionalized Hydrazones and Tetrahydropyridazines

Abstract

A 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)-promoted intermolecular addition reaction two molecules of nitroalkanes to diazo compounds has been developed, in which diazo compounds sereve as the efficient N-terminal electrophiles. The reaction provides two new and highly efficient methods for the construction of functionalized hydrazones and tetrahydropyridazines bearing the structure feature of nitroalkanes from readily available starting materials. The reaction involves a sequential intermolecular nucleophilic addition/elimination/intermolecular Aza-Henry reaction/intramolecular cyclization procedure where two or three adjacent stereocenters are created simultaneously in one-pot manner.