Similarly, using diketene to replace mixedanhydride or acid chloride, intermediate enol 5 May be obtained.
而由混合酸酐或双烯酮代替酰氯，中间体也可能是烯酮或烯醇5。
2
Chiral imine 1 derived from (r) glyceraldehyde acetonide could rapidly react with ketenes 2 which was converted from mixedanhydride or acid chloride under mild conditions.