Total Synthesis of Diocollettines A via an Acid-Promoted Oxa-Michael-Aldol-Acetalization Cascade
Total Synthesis of Diocollettines A via an Acid-Promoted Oxa-Michael-Aldol-Acetalization Cascade
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DOI：
10.1021/acs.orglett.9b04074
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发表时间：
2019-12-20
期刊：
影响因子：
5.2
通讯作者：
Kuwahara, Shigefumi
中科院分区：
文献类型：
--
作者：
Kawamoto, Misaki;Sato, Shuntaro;Kuwahara, Shigefumi
通过四个步骤，从市售的 3-苯基丙醛中实现了具有不寻常的含氧三环系统的 diocollettines A 的非对映和对映选择性全合成，总产率为 63%。本合成的关键特征是完全的非对映选择性级联序列，由 1,3-二羟基丙酮反式选择性 oxa-Michael 加成到 2,3-二氢吡喃鎓离子中间体、分子内醇醛型反应和分子内缩醛化组成。
A diastereo- and enantioselective total synthesis of diocollettines A with an unusual oxygen-containing tricyclic ring system has been achieved in 63% overall yield from commercially available 3-phenylpropanal via four steps. The key feature of the present synthesis is an exclusively diastereoselective cascade sequence composed of a trans-selective oxa-Michael addition of 1,3-dihydroxyacetone to a 2,3-dihydropyrylium ion intermediate, intramolecular aldol-type reaction, and intramolecular acetalization.