Photodecarboxylative chlorination of carboxylic acids via their benzophenone oxime esters
作者:Masato Hasebe、Takashi Tsuchiya
DOI:10.1016/s0040-4039(00)82327-8
日期:1988.1
Decarboxylative chlorination of various aromatic and aliphatic carboxylic acids is performed successfully by the photolysis of their benzophenone oxime esters in carbon tetrachloride and corresponding chloro compounds are prepared in good yields. High selective generation of the certain radical and efficiency of the stable radical precursor, benzophenone oxime ester, afford much advantage for radical
The effective formation of 1-azabicyclo[3.1.0]hexane (5) by treatment of 2-(bromomethyl)pyrrolidine hydrobromide (4) with n-BuLi was established, with the reaction occurring by a rational reaction pathway via the open chain transition state 8 based on intermolecular Br...Li(+) coordination (SN2 process). The reaction of 5 with electrophiles 13a-n gave the corresponding pyrrolidines 14a-n and piperidine
5-<i>Exo</i> versus 6-<i>Endo</i> Cyclization of Primary Aminyl Radicals: An Experimental and Theoretical Investigation
作者:Feng Liu、Kun Liu、Xinting Yuan、Chaozhong Li
DOI:10.1021/jo7015967
日期:2007.12.1
The cyclization of neutral primary pent-4-enylaminyl radicals was investigated experimentally and theoretically. Unlike the corresponding secondary aminyl radicals, primary pent-4-enylaminyl radicals underwent efficient cyclization to afford the pyrrolidine and/or piperidine products in good to high yields. While the simple pent-4-enylaminyl radical gave predominately the 5-exo, cyclization product, 4-chloropent-4-enylarninyl radicals led to the formation of the corresponding 6-endo cyclization products in excellent regioselectivity. Theoretical calculations revealed that the 5-exo cyclization rate of primary aminyl radicals is about 3-4 orders of magnitude higher than that of secondary aminyl radicals.
HASEBE, MASATO;TSUCHIYA, TAKASHI, TETRAHEDRON LETT., 29,(1988) N 48, C. 6287-6290