Preparation of cyclic α-(3,4-dihydro-2-isopropyl-4-oxoquinazolin-3-yl)amino-β-ketoesters: Further oxidation with lead tetra-acetate in dichloromethane and in methanol leading to ring-expansion and ring-cleavage products, respectively
作者:Robert S. Atkinson、Emma Barker、Paul J. Edwards、Gordon A. Thomson
DOI:10.1016/0040-4039(94)80138-x
日期:1994.10
Cyclic β-ketoesters e.g. 7 and the enol silyl ether 18 are converted to the corresponding α-(quinazolinonyl)amino (α-Q′NH) derivatives 10 and 19 respectively by reaction with the 3-acetoxyaminoquinazolinone 6: further oxidation of 10 and 19 with lead tetra-acetate in dichloromethane gave ring-expanded products 15 and 20 respectively but with methanol as solvent the corresponding ring-cleaved products
通过与3-乙酰氧基氨基喹唑啉酮6反应,分别将环状β-酮酸酯(例如7)和烯醇甲硅烷基醚18分别转化为相应的α-(喹唑啉酮基)氨基(α-Q'NH)衍生物10和19:进一步氧化10和19用四乙酸铅在二氯甲烷中的溶液分别得到扩环产物15和20,但是用甲醇作为溶剂,得到相应的环裂解产物21和22:似乎不涉及自由基中间体。