- 作者: 雷敏宏; 陳振鑾; 劉秀齡
- 作者服務機構: Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 107
- 中文摘要:
Previous publication showed that the stereochemistry of lithium aluminum hydride reduction of cyclic ketones can be evaluated by the use of an empirical equation, .DELTA.(.DELTA.G/sup neq/)/sub H/=.DELTA..sigma.+.DELTA..pi.=.DELTA.(.DELTA.G/sup neq/)/sub M/sub e//+1.4.DELTA.G.degree./sub H/. This paper reports further test of this relationship in the new system of 2,2-dimethyl-4-t-butyl-cyclohexanone.
Lithium aluminum hydride reduction of this ketone yields 95.6% trans-alcohol (lit., 95.9%) corresponding to .DELTA.(.DELTA.G/sup neq/)/sub H/ of 1.67Kcal/mol. With methyllithium, the ketone formed 77.5% of trans-alcohol (.DELTA.(.DELTA.G/sup neq/)/sub M/sub e//=0.67Kcal/mol). These data give a calculated .DELTA.G.degree.=0.74Kcal/mol which agrees well with the literature value 0.87 or 0.28Kcal/mol.
Structural assignments of 2,2-dimethyl-4-t-butylcyclohexanone, 1,2,2-trimethyl-cis- and trans-4-t-butylcyclohexanols by pmr spectroscopic method are also given. - 英文摘要: --
- 中文關鍵字: Stereochemistries; 2,2-Dimethyl-4-t-Butylcyclohexanone Systems.
- 英文關鍵字: Stereochemistries; 2,2-Dimethyl-4-t-Butylcyclohexanone Systems.