Enantioselective Total Synthesis of (−)-Δ<sup>9</sup>-Tetrahydrocannabinol via N-Heterocyclic Carbene Catalysis
作者:Adam Ametovski、David W. Lupton
DOI:10.1021/acs.orglett.9b00198
日期:2019.2.15
Enantioselective syntheses of (−)-Δ8-tetrahydrocannabinol ((−)-Δ8-THC) and (−)-Δ9-THC have been achieved in eight and 10 steps, respectively, from a known cinnamic acid. The syntheses take advantage of an enantioselective N-heterocyclic carbene (NHC)-catalyzed (4 + 2) annulation between donor–acceptor cyclobutanes and cinnamoyl fluorides to construct the highly enantioenriched cycloxyl β-lactone shown
的对映体选择性合成( - ) - Δ 8四氢大麻酚(( - ) - Δ 8 -THC)和( - ) - Δ 9 -THC在8个10个步骤,分别而完成的,从已知的肉桂酸。合成利用供体-受体环丁烷和肉桂酰氟之间的对映选择性N-杂环卡宾(NHC)催化(4 + 2)环化反应来构建所示的高度对映体富集的环己基β-内酯。具有此构造的A-环前体,拟订( - ) - Δ 8 -THC通过β内酯醇解随后氧化,双脱羧,三甲基,和阳离子环化来实现的。最后,转化为( - ) - Δ 9 -THC与建立化学实现。