1,2,3- And 1,2,4-trisubstituted cyclopentadienyl manganese tricarbonyl compounds have been synthesized regioselectively from furans following a common synthetic strategy. The key steps include the transformation of furylcarbinols into hydroxycyclopentenones followed by the conjugate addition of Grignard reagents under chelation directed conditions. This affords hydroxycyclopentanones which can be dehydrated to cyclopentenones. These compounds are further elaborated into the final targets by the 1,2-addition of organolithium reagents.
我们采用一种常见的合成策略,从
呋喃中选择性地合成了 1,2,3- 和 1,2,4- 三取代的
环戊二烯基三羰基
锰化合物。关键步骤包括将
呋喃甲醇转化为羟基
环戊烯酮,然后在螯合定向条件下与
格氏试剂共轭加成。这样就得到了羟基
环戊酮,而羟基
环戊酮可以脱
水成
环戊烯酮。通过
有机锂试剂的 1,2-加成,这些化合物可进一步转化为最终目标物。