The title induction has been observed in the reaction of achiral 2,2',6,6'-tetrakis(bromomethyl)biphenyl with centrally chiral (R)-1-phenylethylamine, (R)-1-(1-naphthyl)ethylamine and (R)-1-(2-naphthyl)ethylamine. The ratio of the arising diastereomeric doubly bridged diamines and their thermodynamic stability have been determined. The diastereomer excess in the kinetically controlled reaction is solvent-dependent. The absolute configuration of the biphenyl twist in the products has been assigned on the basis of CD spectra and comparison with singly bridged biphenyl models of known sense of the twist.
在无手性2,2',6,6'-四
溴甲基联苯与中心手性(
R)-1-苯
乙胺、(
R)-1-(1-
萘基)
乙胺和(
R)-1-(2-
萘基)
乙胺反应中观察到了诱导现象。已确定了产生的二重桥联双胺的对映异构体比例及其热力学稳定性。在动力学控制的反应中,对映异构体过量取决于溶剂。通过CD光谱和已知扭曲方向的单重桥联
联苯模型的比较,已经确定了产物中
联苯的绝对构型。