Synthesis and Acid-Catalyzed Cyclization of 2-Alkenylstilbenes: a New Approach to the Substituted Indenes
作者:Wei Ding、Xiaoxin Shi、Xia Lu
DOI:10.1002/cjoc.201500587
日期:2015.11
A base‐catalyzed ring‐opening of 1‐benzylisochromans 1 firstly produced 2‐alkenylstilbenes 2, which then underwent a mild acid‐catalyzed intramolecular cyclization to furnish 1,2‐disubstituted indenes 3 in high yields. Subsequently, a base‐catalyzed isomerization of the 1,2‐disubstituted indenes 3 afforded the more stable 2,3‐disubstituted indenes 4 in almost quantitative yields.
碱催化的1-苄基异氰酸酯1的开环首先产生2-链烯基苯乙烯2,然后对其进行温和的酸催化的分子内环化,以高产率提供1,2-二取代的茚满3。随后,1,2-二取代的茚3的碱催化异构化以几乎定量的产率提供了更稳定的2,3-二取代的茚4。