Multi-component, One-pot Synthesis Of Multi-substituted Pyrano"2,3-c"pyrazols

Multi-substituted pyran, pyrazole and pyrano-pyrazole compounds were widely used in the field of medicine and pesticides because of their wide range and good biological activity such as anti-allergic, anticancer, hypoglycemic, anti-inflammatory, antibacterial, and insecticidal, etc. In order to provide a new synthetic method for pyrano[2,3-c]pyrazoles, we designed a multi-component one-pot synthesis of multi-substituted pyrano [2,3-c] pyrazoles.Based on previous studies of our group, multi-component one-pot synthesis of multi-substituted pyrano [2,3-c] pyrazoles were studied in detail. The high yield of products were obtained under catalyze by triethylamine were obtained in high yield product. In addition, the reaction mechanism of the three components and four components reactions were also discussed. This paper has certain theoretical and applied research value.This thesis is composed of two parts:The first part is about literature review. The research progress and the main synthesis methods on pyran derivatives and pyrano-pyrazole compounds were briefly described.The second part is experimental content, which divide into three main parts.1. Three-component one-pot synthesis of multi-substituted pyrano [2,3-c]pyrazole: In this part, 6-amino-4-phenyl-1,4-dihydro-3-methyl-1-phenyl pyrano[2,3-c]pyrazol-5- carbonitriles (7a-7j) were synthesized by three-component one-pot reaction, and the structures of title products were characterized using IR, 1H NMR and MS spectra.2. Four-component one-pot synthesis of multi-substituted pyrano [2,3-c] pyrazole: In this part, 6-amino-4-phenyl-1,4-dihydro-3-methyl-1-phenyl pyrano[2,3-c] pyrazol-5-carbonitriles (7a-7j), 6-Amino-4-phenyl-1,4-dihydro-3-ethyl-1-phenyl pyrano[2,3-c]pyrazol-5-carbonitriles (9a-9j) and 6-amino-4-phenyl-3-isopropyl- 1-phenyl-4H-pyrano[2,3-c]pyrazol-5-carbonitriles (11a-11j) were synthesized repectively by four-component one-pot reaction, and the structures of title products were characterized using IR, 1H NMR and MS spectra.3. Four-component one-pot synthesis of multi-substituted pyrano[2,3-c]pyrazole dimmers: Multi-substituted dimerpyrano[2,3-c]pyrazole-5-carbonitriles were synthesized by four-component one-pot reaction ofβ-keto-ester, hydrazine, benzenedialdehyde and malononitrile under triethylamine catalyst, and the structures of title products were characterized using IR, 1H-NMR and MS spectra.