From Central to Helical Chirality: Synthesis ofP andM Enantiomers of[5]Helicenequinones and Bisquinones from (SS)-2-(p-Tolylsulfinyl)- 1,4-benzoquinone
作者:M. Carmen Carreño、Susana García-Cerrada、Antonio Urbano
DOI:10.1002/chem.200304835
日期:2003.9.5
The reaction of 1,4-divinyl-1,3-cyclohexadiene, 5,8-dimethoxy- or tert-butyldimethylsilyloxy-3-vinyl-1,2-dihydrophenanthrene or 6-vinyl-7,8-dihydro-1,4-phenanthrenequinone with an excess of enantiopure (SS)-2-(p-tolylsulfinyl)-1,4-benzoquinone (2) led to the direct formation of enantioenriched dihydro[5]helicenequinones or bisquinones (50-->98 % ee). A domino Diels-Alder cycloaddition/sulfoxide elimination/partial
1,4-二乙烯基-1,3-环己二烯,5,8-二甲氧基-或叔丁基二甲基甲硅烷氧基-3-乙烯基-1,2-二氢菲或6-乙烯基-7,8-二氢-1,4-的反应菲醌与过量的对映体纯(SS)-2-(对甲苯基亚磺酰基)-1,4-苯醌(2)导致直接形成对映体富集的二氢[5]芴醌或双醌(50-> 98%ee)。发生多米诺Diels-Alder环加成/亚砜消除/部分芳构化过程,这是在芳构化步骤中定义的最终螺旋烯的绝对构型。如果在(+/-)-2,DDQ,CAN或DBU的存在下芳构化了两个第一步的五环二氢芳族中间体,则M和P的Helimer都可以通过逐步对映发散过程获得。