Carbanion induced, base-catalyzed, synthesis of highly functionalized 8-aryl-3,4-dihydro-2(1H)-naphthalenones from 2H-pyran-2-ones

A general and efficient synthesis of 8-aryl-5-methoxycarbonyl-6-methylsulfanyl-3,4-dihydro-2(1H)-naphthalenones 4a–i and 8-aryl-5-cyano-6-sec-amino-3,4-dihydro-2(1H)-naphthalenones 4l–r has been delineated from the acid hydrolysis of 8-aryl-5-methoxycarbonyl-6-methylsulfanyl-3,4-dihydro-2(1H)-naphthalenone-(2,2-dimethyltrimethylene)ketals 3a–i and 8-aryl-5-cyano-6-sec-amino-3,4-dihydro-2(1H)-naphthalenone-(2,2-dimethyltrimethylene) ketals 3l–r, obtained from the reaction of 6-aryl-3-methoxycarbonyl-4-methylsulfanyl-2H-pyran-2-ones 1a–i and 3-cyano-6-aryl-4-sec-amino-2H-pyran-2-ones 1l–r with 1,4-cyclohexanedione mono-(2,2-dimethyltrimethylene)ketal 2.