Synthesis, spectral and structural characterization of isobutyl 4-(2-chlorophenyl)-5-cyano-6-(((dimethylamino)methylene)amino)-2-methyl-4H-pyran-3-carboxylate

A fascinating selectivity in the direction of the formation of the formamidine was observed upon the reaction of isobutyl 6-amino-4-(2-chloropheny1)-5-cyano-2-methy1-4H-pyran-3-carboxylate with N,N-dimethyl formamide. A development in selectivity is explored and a probable mechanism for the reaction is also proposed. The formamidine has been analyzed by FT-IR, FT-Raman, LC-MS and NMR (1D and 2D (H-1-H-1 COSY, H-1 -C-13 COSY and HMBC)) spectra. The experimental findings are compared with the theoretical data calculated by using DFT-B3LYP with 6-311++G(d,p) basis set. A good agreement has been observed between experimental and theoretical data. Single crystal X-ray structural analysis of isobutyl 4-(2-chloropheny1)-5-cyano-6-(((dimethylamino)methylene)amino)-2-methyl-4H-Pyran-3carboxylate (PDMF), evidences the conformation of pyran ring as "flattened boat". (C) 2017 Elsevier B.V. All rights reserved.