Reaction of Highly Methylated 2-Methylenecycloalkyl Hydroperoxides with FeSO<sub>4</sub>/CuCl<sub>2</sub>. Remarkably Efficient 5-<i>e</i><i>ndo</i>-<i>t</i><i>rig</i> or 6-<i>e</i><i>ndo</i>-<i>t</i><i>rig </i>Cyclization of the Intermediate Carbon Radicals
作者:Yuji Nonami、Janusz Baran、Jacek Sosnicki、Herbert Mayr、Araki Masuyama、Masatomo Nojima
DOI:10.1021/jo990127a
日期:1999.5.1
Treatment of 1,3,3 4,4,5,5-heptamethyl-2-methylenecyclopentyl hydroperoxide, derived from a singlet oxygen ene reaction of 1,2,3,3,4,4,5,5-octamethylcyclopentene, with FeSO4/CuCl2 gave 1-chloro-2,2,3,3,4,4-hexamethylcyclopentyl methyl ketone in high yield, suggesting that the consecutive O-O and C-C bond fission is followed by a novel 5-endo-trig cyclization of the intermediate carbon radical to the activated C-C double bond. In the case of 1,3,3,6,6-pentamethyl-2-methylene-1-cyclohexyl hydroperoxide also, an efficient 6-endo-trig cyclization of the corresponding carbon radical was realized giving 1-chloro-2,2,5,5-tetramethylcyclohexyl methyl ketone in high yield.