Cyclization of the Grignard reagent from 5-chloro-3-methyl-1-hexene; a reversible organomagnesium rearrangement
作者:E.Alexander Hill、Marion M. Myers
DOI:10.1016/s0022-328x(00)91230-0
日期:1979.7
The Grignard reagent from 5-chloro-3-methyl-1-hexene cyclized reversibly to form an equilibrium mixture with two stereoisomers of the 2,4-dimethylcyclobutylmethyl-Grignard reagent. Equilibrium and rate constants for the opposing reactions have been evaluated at 80–100 and 100–120°C, respectively. Over this range, the equilibrium mixture favors the cyclic reagent by a ratio of about . Comparison with
来自5-氯-3-甲基-1-己烯的格氏试剂可逆地环化以形成与2,4-二甲基环丁基甲基-格氏试剂的两个立体异构体的平衡混合物。分别在80–100和100–120°C下评估了相反反应的平衡常数和速率常数。在此范围内,平衡混合物以约的比例有利于环状试剂。与相关化合物的结果比较表明,甲基取代会通过有机镁功能的不稳定和应变环的稳定来影响平衡。讨论了速率常数和平衡常数的其他比较。