Synthesis and fluxional behavior of dinaphtho[2,1-b;1′,2′-d]-siloles and -germoles, involving the first example of optically active group 14 dinaphthoheterols
作者:Shuji Yasuike、Tomoyasu Iida、Satoru Okajima、Kentaro Yamaguchi、Hiroko Seki、Jyoji Kurita
DOI:10.1016/s0040-4020(01)01067-5
日期:2001.12
7-Substituted dinaphtho[2,1-b;1′,2′-d]-siloles 2 and -germoles 3, involving the first isolated example of optically active group 14 dinaphthoheteroles, have been prepared from 2,2′-dibromo-1,1′-binaphthyl (DBBN) via 2,2′-dilithio-1,1′-binaphthyl intermediate. They are fluxional in the NMR time scale at elevated temperatures, and the energy barriers (ΔG‡) for racemization arising from the flipping of the two naphthalene
7-取代的二萘并[2,1- b ; 1',2'- d ] -siloles 2和-germoles 3,涉及光学活性基团14个dinaphthoheteroles的第一分离例如,已经从2,2'-二溴制备1,2'-联萘(DBBN)经由2,2'-dilithio-1,1'-联萘中间体。它们在升高的温度下在NMR时间尺度上是通量的,并且两个硅环2b – d的两个萘环的翻转引起的外消旋化的能垒(ΔG ‡)估计为76–77±2 kJ mol -1。芽3b为80±2 kJ mol -1。半衰期(t 1/2)的光学外消旋体(R)-2b的消旋作用是由旋光性(R)-DBBN通过相同的程序制备的,在苯中于19°C确定为7.2 h。