Improve Method for Synthesis of 4-Thioaryl-2,3,4-trihydro-1-benzothiopyrans: Acid-induced Stereoselective Intermolecular Cycloaddition of α,β-Unsaturated Aldehydes with Arenethiols
作者:Yoshio Ishino、Masatoshi Mihara、Hidehito Kawai
DOI:10.1055/s-2001-16071
日期:——
A catalytic amount of acids catalyzed reaction of α,β-unsaturated aldehydes with arenethiols in 1,2-dichloroethane brought about intermolecular cycloaddition to give the corresponding 4-thioaryl-2,3,4-trihydro-1-benzothiopyrans (thiochromans) in good to excellent yield. These reactions are assumed to proceed through allylic cationic intermediates generated in site.
Stereoselective Synthesis of 2,4-Disubstituted Thiochromans Using the Supported Reagent System ‘Na<sub>2</sub>CO<sub>3</sub>/SiO<sub>2</sub>-PPA/SiO<sub>2</sub>’
A simple and efficient method has been developed for the stereoselectivesynthesis of 2,4-disubstituted thiochromans from arylthiols and α,β-unsaturated aldehydes by using an acid- and a base-supported reagent system, Na 2 CO 3 /SiO 2 -PPA/SiO 2 . Michael addition of arylthiol to α,β-unsaturated aldehydes was promoted by Na 2 CΟ 3 /SiΟ 2 , and then the product was cyclized in the presence of PPA/SiO
开发了一种简单有效的方法,通过使用酸和碱负载的试剂体系 Na 2 CO 3 /SiO 2 -PPA,从芳基硫醇和 α,β-不饱和醛立体选择性合成 2,4-二取代硫色满/SiO 2 。Na 2 CO 3 /SiO 2 促进芳硫醇与α,β-不饱和醛的迈克尔加成反应,产物在PPA/SiO 2 存在下进行环化。
Labiad, B.; Villemin, D., Synthetic Communications, 1989, vol. 19, # 1, 2, p. 31 - 38
作者:Labiad, B.、Villemin, D.
DOI:——
日期:——
LABIAD, B.;VILLEMIN, D., SYNTH. COMMUN., 19,(1989) N-2, C. 31-38
作者:LABIAD, B.、VILLEMIN, D.
DOI:——
日期:——
NAKAZAWA, TOSHIKATSU;SATO, KAZUO;ITABASHI, KUNIO, NIPPON KAGAKU KAJSI,(1990) N, S. 115-118