In the presence of a catalytic amount of bis(dipivaloylmethanato)manganese(II) (= Mn(dpm)2), various cholesterol derivatives are smoothly converted into the corresponding β-epoxides in good to high yields with combined use of molecular oxygen and isobutyraldehyde. These stereoselectivities are the reversal of the cases using peracid such as mCPBA.
在使用催化量的双(二戊酰甲
酮酸)
锰(II)(= Mn(dpm)2)的存在下,多种
胆固醇衍
生物能够顺利地转化为相应的高产率至高产率的β-
环氧化物,这需要结合分子氧和
异丁醛的使用。这些立体选择性与使用过酸如mCPBA的情况相反。