Stereoselective synthesis of side chain-functionalized tetrahydropyrans from 5-hexenols
作者:Patrick Fries、Melanie Kim Müller、Jens Hartung
DOI:10.1016/j.tet.2013.12.019
日期:2014.2
products of 6-exo-bromocyclization, as exemplified by synthesis of diastereomerically pure 2,4,6-substituted tetrahydropyrans. The cobalt method extends to intermolecular alkene/alkanol cross-coupling and to multi-component reactions between dimethyl fumarate, CHD, a 5-hexenol, and dioxygen, providing α-tetrahydropyranyl-2-methyl succinates in synthetically useful yields.
当被氟代钴激活时,分子氧通过氧化环化/自由基官能化级联将5-己醇选择性地转化为2-甲基四氢吡喃的2,6-反式,2,5-反式和2,4-顺式衍生物( II)在环己-1,4-二烯(CHD)溶液中的双-(β-二酮酮)络合物。溴三氯甲烷和CHD溶液中的好氧5-己烯氧化提供了6-外-溴环化的产物,以非对映体纯的2,4,6-取代的四氢吡喃的合成为例。钴方法扩展到分子间烯烃/链烷醇的交叉偶联以及富马酸二甲酯,CHD,5-己烯醇和双氧之间的多组分反应,从而以合成上有用的产率提供α-四氢吡喃基-2-甲基琥珀酸酯。