顺(反)-2,4,7-三芳基5-氧代-4 H-5,6,7,8-四氢苯并吡喃衍生物的合成

Synthesis of cis- and trans-2,4,7-Triaryl-5-oxo-4H-5,6,7,8-tetrahydrobenzopyrans

在酸或碱性条件下 ,5 ,5 二甲基 1,3 环己二酮和 5 芳基 1,3 环己二酮与查尔酮首先进行Michael加成反应 ,进而环合为 7,7 二甲基 2 ,4 二芳基 5 氧代 4H 5 ,6,7,8 四氢苯并吡喃衍生物和含有两个手性原子的顺 和反 2 ,4,7 三芳基 5 氧代 4H 5 ,6,7,8 四氢苯并吡喃衍生物 .讨论了反应机理并且通过1HNMR光谱和NOE差谱确定其产物构型 .所合成新的多氢苯并吡喃衍生物的分子结构均经红外光谱、核磁共振光谱和元素分析予以证实 .

Michael addition of 5-aryl-1,3-cyclohexanedione to the chalcones was carried out in the acidic or basic condition to give the corresponding cis- and trans-2,4,7-triaryl-5-oxo-4H-5,6,7,8-tetrahydrobenzopyrans bearing two chiral atoms. The structures and configurations of the products were confirmed by elemental analysis, IR, H-1 NMR and NOE, and the reaction mechanism was discussed as well.