Microwave-accelerated and efficient synthesis of structurally diverse N-(2,2-diphenylvinyl)-β-oxoamides

N-(2,2-Diphenylvinyl)-beta-oxoamides are both the structural moiety of biologically active compounds and important synthetic intermediates. Structurally diverse N-(2,2-diphenylvinyl)-beta-oxoamides are prepared efficiently from 2-diazo-1,3-dicarbonyl compounds and N-alkyl-2,2-diphenylaziridines via an electrophilic ring opening reaction under two different reaction conditions of reflux and microwave irradiation. 2-Diazo-1,3-dicarbonyl compounds undergo the Wolff rearrangement under heating to generate alpha-oxoketenes, which electrophilically react with N-alkylaziridines to directly produce structurally diverse N-(2,2-diphenylvinyl)-beta-oxoamides in good to excellent yields under microwave irradiation. Microwave irradiation accelerates the reaction obviously and efficiently. Both 2-diazo-1,3-diketones and alkyl 2-diazo-3-oxoalkanoates work well. The reaction is catalyst-free and highly atom economical, involves only loss of nitrogen and does not require additives. The products are useful synthons for the convenient preparation of multisubstituted beta-lactam derivatives.

Automated summary

The structurally diverse N-(2,2-diphenylvinyl)-beta-oxoamides were efficiently prepared via an electrophilic ring opening reaction, with microwave irradiation significantly accelerating the reaction rate and yielding products of good to excellent quality. This catalyst-free method is highly efficient and atom economical for the synthesis of useful synthons.