Rhodium/alumina catalysed cis-hydrogenation of the known enol-acetate 7 proceeded quantitatively and with complete stereoselectivity leading to the D-gulose derivative 8. Several reaction steps permitted transformation of 8 into the target D-xylo-imidazolopiperidinose ent-4 molecule, i.e. the enantiomer of the already known imidazolo-sugar 4.
铑/氧化铝催化的已知烯醇-
乙酸酯7的顺式氢化反应是定量进行的,并且具有完全的立体选择性,从而生成
D-古洛糖衍
生物8。几个反应步骤允许将8转化为目标
D-木糖-
咪唑并
哌啶子糖ent - 4分子,即已知
咪唑糖4的对映异构体。