Enantioselective Construction of Spiro[chroman‐thiazolones]: Bifunctional Phosphonium Salt‐Catalyzed [2+4] Annulation between 5‐Alkenyl Thiazolones and
<i>ortho</i>
‐Hydroxyphenyl‐Substituted
<i>para‐</i>
Quinone Methides
作者:Jian‐Ping Tan、Hongkui Zhang、Zhiyu Jiang、Yuan Chen、Xiaoyu Ren、Chunhui Jiang、Tianli Wang
DOI:10.1002/adsc.201901413
日期:2020.3.4
The enantioselectiveformal [2+4] annulation of 5‐alkenyl thiazolones with hydroxyl‐substituted para‐quinone methides was disclosed by dipeptide‐based phosphonium salt catalysts. A wide range of functionalized spiro‐chroman‐thiazolone molecules bearing three contiguous 3° and/or 4° stereocenters were readily constructed in high yields with excellent stereoselectivities (>20:1 dr and up to >99.9% ee)