Asymmetric Synthesis of Spiropyrazolone-Fused Dihydrofuran-naphthoquinones Bearing Contiguous Stereocenters via a Michael Addition/Chlorination/Nucleophilic Substitution Sequence
作者:Gaihui Li、Hongyu Zhang、Guoshun Zhang、Bei Wei、Bin Liu、Heng Song、Qingshan Li、Shurong Ban
DOI:10.1021/acs.joc.2c03013
日期:——
An enantioselective synthesis of spiropyrazolone-fused dihydrofuran-naphthoquinones is first demonstrated via a Michael addition/Chlorination/Nucleophilic substitution sequence. The reactions of 2-hydroxy-1,4-naphthoquinone and α,β-unsaturated pyrazolones in the presence of the cinchona alkaloid derived hydrogen-bonding catalyst and NCS provide spiropyrazolone-fused 2,3-dihydronaphtho[2,3-b]furan-4
首先通过迈克尔加成/氯化/亲核取代序列证明了螺吡唑啉酮稠合二氢呋喃-萘醌的对映体选择性合成。2-羟基-1,4-萘醌和 α,β-不饱和吡唑啉酮在金鸡纳生物碱衍生的氢键合催化剂和 NCS 存在下的反应提供螺吡唑啉酮稠合的 2,3-二氢萘并 [2,3-b ]呋喃-4,9-二酮具有连续的立构中心,其中一个是高产率的螺四元立构中心,具有独特的非对映选择性和良好至优异的对映选择性。