A series of bis(2-tetrahydrobenzofuranyl)alkanes were efficiently prepared in high yields (69-98%) from 3-methyl-6,7-dihydrobenzofuran-4(5H)-ones and aldehydes under solvent-free conditions. The eco-friendly condensation reaction was smoothly catalyzed by H 2 SO 4 •SiO 2 (30% w/w) in three minutes at 90 ºC, and the catalyst could also be recycled up to nine successive cycles without significant loss in catalytic activity.
A high‐efficient and stereo‐specific approach for the preparation of biologically important (E)‐2‐styryl‐tetrahydrobenzo[d]thiazoles has been developed via TMSCl promoted direct sp3 C‐H alkenylation of 2‐methyl‐5,6‐dihydrobenzo[d]thiazol‐7(4H)‐one under metal‐free conditions. Seventeen target compounds were synthesized in excellent yields of 82% –98% under the optimal conditions of 300 mol% TMSCl at 110°C for 2 h, and their chemical structures were elucidated by IR, NMR, ESI‐MS, elemental analyses and X‐ray crystallography analysis. A plausible mechanism was also proposed, and this method provided a good functional group conversion for the sp3 C‐H substrates.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.