Atropisomerism of the 1,3-cyclohexadiene Derivatives Induced by Steric Congestion
作者:Juzo Nakayama、Kazuki Iguchi、Takashi Fujihara
DOI:10.1080/10426501003773472
日期:2010.5.27
reacted with maleic anhydride to give the Diels–Alder adduct quantitatively. Oxidation of the sulfinyl group of the adduct and the thermal extrusion of sulfur dioxide from the resulting sulfone furnished 4,5-di-tert-butyl-3,6-dimethyl-3,5-cyclohexadiene-1,2-dicarboxylic acid anhydride (8) quantitatively. 8 showed atropisomerism that originates from the inhibited ring inversion of the cyclohexadiene ring
3,4-二叔丁基-2,5-二甲基噻吩 1-氧化物 (2) 与马来酸酐反应,定量得到 Diels-Alder 加合物。加合物的亚磺酰基的氧化和二氧化硫从所得砜中的热挤出提供了 4,5-二叔丁基-3,6-二甲基-3,5-环己二烯-1,2-二羧酸酐( 8)定量。图 8 显示了阻转异构现象,其源于空间拥塞抑制环己二烯环的环反转。阻转异构体的混合物也可从 2 和 1,4-苯醌的加合物中获得。