One pot diastereoselective synthesis of new chiral spiro-1,3,4-thiadiazoles and 1,4,2-oxathiazoles from (1<i>R</i>)-thiocamphor
作者:Amal Feddouli、Moulay Youssef Ait Itto、Aïssa Hasnaoui、Didier Villemin、Paul-Alain Jaffrès、Jana Sopkova-De Oliveira Santos、Abdelkhalek Riahi、FranÇOis Huet、Jean-Claude Daran
DOI:10.1002/jhet.5570410513
日期:2004.9
Herein we report an efficient one pot synthesis of new chiral 4,5-dihydro-4-arylspiro[1,3,4-thiadiazole]-5,2′-camphane-2-carboxylic acid ethyl esters 5–7 and 4,5-dihydro-3-arylspiro[1,4,2-oxathiazole]-5,2′-camphane 11–13, using 1,3-dipolar cycloaddition of nitrilimines 2–4 and nitrile oxides 8–10 to (1R)-thiocamphor 1 respectively. The structure of the newly prepared 1,3,4-thiadiazoles 5–7 (obtained
在这里,我们报告了一种有效的一锅合成新的手性4,5-二氢-4-芳基螺[1,3,4-噻二唑] -5,2'-camphane-2-羧酸乙酯5-7和4,5 -dihydro-3-arylspiro [1,4,2-oxathiazole] -5,2'-camphane 11–13,使用1,3-偶极环加成亚胺2–4和一氧化氮8–10至(1 R)-硫樟1。通过光谱分析和X射线结构分析完全确定了新制备的1,3,4-噻二唑5–7(作为纯非对映异构体获得)的结构,证明了C5螺碳的绝对构型为(R)。NMR光谱分析也非常有用,它表明新的1,4,2-氧杂噻唑11-13是两种(5 R)/(5 S)非对映异构体的混合物,比例分别为6:4,7:3和6:4 。