Regioselective monoalkylations of the vicinal cis-diol group in mannopyranosides using diaryldiazoalkanes-tin(II) chloride
作者:Sigthor Petursson、John M. Webber
DOI:10.1016/s0008-6215(82)80006-2
日期:1982.5
Abstract Highly regioselective monoalkylations of the cis -2,3-diol group in mannopyranosides can be achieved with diaryldiazoalkanes in the presence of catalytic amounts of tin(II) chloride. With diazo(diphenyl)methane ( 1 ), its 4,4′-dimethyl ( 2 ) and 4,4′-dichloro ( 3 ) derivatives, and 9-diazofluorene ( 5 ), methyl 4,6- O -benzylidene- α - d -mannopyranoside gave high yields of the respective
摘要在催化量的氯化锡(II)存在下,使用二芳基重氮烷烃可实现甘露吡喃糖苷中顺-2,3-二醇基团的高度区域选择性单烷基化。与重氮(二苯基)甲烷(1),其4,4'-二甲基(2)和4,4'-二氯(3)衍生物以及9-重氮芴(5),甲基4,6-O-亚苄基-α -d-甘露糖吡喃糖苷分别得到高产率的3-二芳基甲基醚。相比之下,甲基4,6-O-异亚丙基-α-d-甘露吡喃喃糖苷(11)主要生成带有2的3- [双(4-甲基苯基)甲基]衍生物,大约等量的2-和3-醚具有1和3,主要是2与5的醚。用重氮[双(4-甲氧基苯基)]甲烷,11仅得到3-醚(61%)。