Synthesis and Photochemistry of 5,5-Dimethyl-1H-pyrrol-2(5H)-one and of SomeN-Substituted Derivatives
作者:Andreas Ihlefeld、Paul Margaretha
DOI:10.1002/hlca.19920750435
日期:1992.6.24
In two steps, 5,5-dimethyl-1H-pyrrol-2(5H)-one (3a) was prepared from 5,5-dimethylpyrrolidine-2,4-dione ( = dimethyltetramic acid; 4) in 71% overall yield (Scheme 1) and further converted to N-substituted derivatives 3b–fvia acylation, alkylation, or methoxycarbonylation of its anion (Scheme 2). The substituents on the N-atom exert a strong influence on the photochemical reactivity ([2 + 2] photocycloaddition