作者:Mark Lautens、Matthew L. Maddess
DOI:10.1055/s-2004-822401
日期:——
temperature readily affords cyclic enol carbonates with either five- or six-membered rings. Reaction with potassium tert-butoxide results in the in situ formation of an enolate which after transmetallation participates in aldol or Mannich reactions. Alternatively, the potassium enolates can be trapped with silylating or triflating agents. The regio- and stereoselective generation of silyl enol ethers with up
在低温下用 Li
HMDS 处理
碘代
碳酸酯很容易得到具有五元或六元环的环状烯醇
碳酸酯。与
叔丁醇钾反应导致原位形成烯醇化物,其在
金属转移后参与羟醛或曼尼希反应。或者,可以用甲
硅烷基化剂或
三氟甲磺酸酯捕获烯醇
钾。可以实现具有多达四个取代基的甲
硅烷基烯醇醚的区域选择性和立体选择性生成。