Solvolysis of the sulfonate esters of 1-(4,6-dimethyl-s-triazin-2-yl)-2-propanol and 4-(4,6-dimethyl-s-triazin-2-yl)-2-butanol involving a special salt effect and anchimeric assistance
作者:H. LeRoy Nyquist、David A. Davenport、Paul Y. Han、Joseph G. Shih、Thomas G. Speechly
DOI:10.1021/jo00031a023
日期:1992.2
The sulfonate esters of 1-(4,6-dimethyl-s-triazin-2-yl)-2-propanol (2a) and of 4-(4,6-dimethyl-s-triazin-2-yl)-2-butanol (3a) have been synthesized and solvolyzed in formic acid and acetic acid to determine their products and rates. The solvolysis of the esters of 2a gave predominantly alkene, and the results of formolysis are consistent with an E2 mechanism. However, in buffered acetic acid the 20-fold increase in rate relative to the unbuffered acetic acid requires the postulation of an E1cB-like mechanism involving ion pairs and a special salt effect by acetate ion. In contrast, the solvolysis of the sulfonate ester of 3a gave a product (11) which resulted from anchimeric assistance by the triazine ring. Qualitative and quantitative evidence of 11 was obtained from the hydrolysis of 11 and subsequent derivatization of the 4-aminopentanoic acid.