Practical Synthesis of Four Stereoisomers of 6-(<i>t</i>-Butyldiphenylsiloxy)-3,5-dimethyl-1-(triphenylmethoxy)hexane-2,4-diol via Dithiane Coupling with Oxirane
作者:Mitsuaki Ide、Keiji Tsunashima、Masaya Nakata
DOI:10.1246/bcsj.72.2501
日期:1999.11
The anion derived from 2-substituted 1,3-dithiane derivative, (S)-2-[2-(t-butyldiphenylsiloxy)-1-methylethyl]-1,3-dithiane, with n-BuLi at room temperature (r.t.) in THF was subjected to coupling with 2,3-disubstituted oxirane, (2S,3S)- or (2S,3R)-2,3-epoxy-1-(triphenylmethoxy)butane, at r.t., giving the coupling products in satisfactory yield. These coupling products were subjected to de-dithioacetalization, and the resulting carbonyl compounds were stereoselectively reduced to afford four stereoisomers of 6-(t-butyldiphenylsiloxy)-3,5-dimethyl-1-(triphenylmethoxy)hexane-2,4-diol.
从2-取代的1,3-二硫烷衍生物(S)-2-[2-(t-丁基二苯基硅氧基)-1-甲基乙基]-1,3-二硫烷出发,在室温下(r.t.)与n-BuLi在四氢呋喃(THF)中反应,并与2,3-二取代的环氧化物(2S,3S)或(2S,3R)-2,3-环氧-1-(三苯基甲氧基)丁烷进行耦合反应,最终得到满意收率的耦合产物。这些耦合产物经过去二硫醚保护反应,得到的羰基化合物再进行立体选择性还原,最终合成了四种立体异构体的6-(t-丁基二苯基硅氧基)-3,5-二甲基-1-(三苯基甲氧基)己烷-2,4-二醇。