A New Synthesis of 2,2-Disubstituted Cyclopentane-1,3-diones from Succinic Anhydride
作者:I. D. Doyle、R. A. Massy-Westropp、R. F. O. Warren
DOI:10.1055/s-1986-31800
日期:——
Reaction of succinic anhydride (1) with (1-ethoxycarbonylethylidene) triphenylphosphorane (2) gives ethyl 2-(5-oxotetrahydrofur-2-ylidene) propanoate 3. Compound 3 is cleaved with sodium ethoxide to the ß-ketodiester anion, which is treated with alkylhalide to yield the 2,2-disubstituted ß-keto diester 4. Dieckmann cyclization of 4, followed by hydrolysis and decarboxylation, gives rise to 2,2-disubstituted cyclopentane-1,3-diones 5.
琥珀酸酐(1)与(1-乙氧羰基亚乙基)三苯基膦(2)反应,得到 2-(5-氧代四氢呋喃-2-亚基)丙酸乙酯 3。化合物 3 用乙醇钠裂解成 ß-酮二酯阴离子,再用烷基卤化物处理,得到 2,2-二取代的 ß-酮二酯 4。对 4 进行迪克曼环化,然后进行水解和脱羧,得到 2,2-二取代的环戊烷-1,3-二酮 5。