Substituent effects on the regioselectivity of the baeyer-villiger oxidation of 7-oxabicyclo[2.2.1]heptan-2-ones
作者:Geza Arvai、Fattori Daniela、Pierre Vogel
DOI:10.1016/s0040-4020(01)88358-7
日期:1992.11
New 3-oxy substituted and 3,6-dioxydisubstituted 7-oxabicyclo[2.2.1]heptan-2-ones have been prepared. The regioselectivity of their Baeyer-Villiger oxidation has been determined and compared with that of other 7-oxabicyclo[2.2.1]heptan-2-one derivatives. If the substituent at C(3-exo) is an O-acyl or another group less electron-releasing, the bridgehead C(1) migration is favoured, leading to 2,8-dioxabicyclo[3
制备了新的3-氧基取代的和3,6-二氧基二取代的7-氧杂双环[2.2.1]庚-2--2-酮。已经确定了其Baeyer-Villiger氧化的区域选择性,并将其与其他7-氧杂双环[2.2.1]庚烷-2-酮衍生物的区域选择性进行了比较。如果在C(3-exo)处的取代基是O-酰基或另一个电子释放性较低的基团,则桥头C(1)迁移受到促进,从而导致2,8-二氧杂双环[3.2.1] octan-3-ones 。当C(3)处的取代基为MeO或(tBu)Me 2 SiO基时,由于优选的C(3)迁移,Baeyer-Villiger氧化导致3,8-dioxabicyclocyclo [3.2.1] octan-2-ones 。后者对3-内-MeO的区域选择性高于对3-exo-MeO取代的酮的区域选择性,并且可以通过C(6- endo)位置的远程氧基取代基来增强。