Synthesis of Bis(germacyclopropa)benzenes and Structures of Their Annelated Benzene Rings
作者:Tomoyuki Tajima、Takahiro Sasamori、Nobuhiro Takeda、Norihiro Tokitoh、Ken Yoshida、Masaru Nakahara
DOI:10.1021/om0507629
日期:2006.1.1
hindered bis(germacyclopropa)benzenes (3a,b; the IUPAC name is 4,8-digermatricyclo[5.1.0.03,5]octa-1,3(5),6-triene) were synthesized as stable crystalline compounds by the reaction of the corresponding dilithiogermane Tbt(Dip)GeLi2 (8; Tbt = 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl, Dip = 2,6-diisopropylphenyl) with 1,2,4,5-tetrabromobenzene. The structures of the two stereoisomeric bis(germacyclopropa)benzenes
极端受阻的双(Germacyclopropa)苯(3a,b ; IUPAC名称为4,8-digermatricyclo [5.1.0.0 3,5 ] octa -1,3(5),6-triene)是稳定的结晶化合物。的二硫代锗烷Tbt(Dip)GeLi 2(8 ; Tbt = 2,4,6-三[双(三甲基硅烷基)甲基]苯基,Dip = 2,6-二异丙基苯基)与1,2,4,5-四溴苯的反应。通过X射线晶体学分析确定地确定了两种立体异构的双(锗环丙烷)苯(3a,顺式异构体;3b,反式异构体)的结构。与3a的平面苯环相反,发现3a的中心苯环被折叠3b。3a和3b的X射线晶体学分析以及某些模型分子的理论计算表明,退火后的苯环没有明显的键交替。