作者:Kristen L. McCaleb、Randall L. Halcomb
DOI:10.1021/ol000145a
日期:2000.8.1
describes intramolecular thermal [2 + 2] cycloadditions between ketenes and allenes. The formation of ketenes and the subsequent cycloadditions occurred under a variety of conditions, affording 7-methylidinebicyclo[3.2.0]heptanones and 7-methylidinebicyclo[3.1.1]heptanones in 45-78% yields. The regioselectivity of the cycloaddition varied with the substitution of the allene, and the yield of cyclized products
[反应:参见文本]该报告描述了烯酮和烯丙烯之间的分子内热[2 + 2]环加成反应。烯酮的形成和随后的环加成反应在各种条件下发生,以45-78%的收率得到7-亚甲基双环[3.2.0]庚烷和7-亚甲基双环[3.1.1]庚烷。环加成的区域选择性随丙二烯的取代而变化,并且环化产物的产率随反应条件而变化。