Straightforward Construction of Fused 6,7,5-Tricarbocyclic Systems by Tandem [5 + 2]/[4 + 2] Cycloadditions
作者:J. Ramón Rodríguez、Antonio Rumbo、Luis Castedo、José L. Mascareñas
DOI:10.1021/jo982050g
日期:1999.2.1
One-pot coupling of an intramolecular thermal [5C + 2C] pyrone-alkene cycloaddition to a [4C + 2C] Diels-Alder reaction provides immediate access to 6,7,5-tricarbocyclic systems bearing a 1,4-oxa-bridge in the seven-membered carbocycle. The transformation entails the net formation of four carbon-carbon bonds and creates three new cycles and a minimum of five new stereocenters. Preliminary attempts
分子内热式[5C + 2C]吡喃烯-烯烃与[4C + 2C] Diels-Alder反应的一锅偶联可立即进入带有1,4-氧杂桥的6,7,5-三环系统七元碳纤维摩托车。转换需要四个碳-碳键的净形成,并创建三个新的循环和最少五个新的立体中心。通过加合物与二碘化sa和三氟甲磺酸三甲基甲硅烷基酯的反应打开氧杂桥的初步尝试导致了相对意想不到的脱氧和芳构化产物。