A Diastereoselective Route to<i>trans</i>-2-Aryl-2,3-dihydrobenzofurans through Sequential Cross-Metathesis/Isomerization/Allylboration Reactions: Synthesis of Bioactive Neolignans
作者:Rémy Hemelaere、François Carreaux、Bertrand Carboni
DOI:10.1002/ejoc.201500019
日期:2015.4
anti-homoallylic alcohols allow the synthesis of the desired skeleton in a stereoselective fashion. As an illustration, we used this strategy for the preparation of the dihydrodehydrodiconiferyl alcohol (1a), a natural dihydrobenzofuran neolignan, as well as for a formal synthesis of its O-demethylated derivative 1b. An enantioselective version of this approach employing a chiral phosphoric acid in the
描述了一种新的高度非对映选择性合成路线,用于反式-2,3-二氢苯并呋喃系统,特别是那些在 C2 位置带有芳基取代基的系统。我们战略的基石是从 2-烯丙基取代的酚和醛开始实施交叉复分解/异构化/烯丙基硼化序列。在分子内 Mitsunobu 环化步骤之后,抗高烯丙醇允许以立体选择性方式合成所需骨架。例如,我们使用这种策略制备了二氢脱氢二松香醇 (1a),一种天然的二氢苯并呋喃新木脂素,以及其 O-去甲基化衍生物 1b 的正式合成。还研究了在烯丙基硼化步骤中使用手性磷酸的这种方法的对映选择性版本。