Regioselective Unusual Formation of Spirocyclic 4-{2‘-Benzo(2‘,3‘-dihydro)furo}- 9-methyl-2,3,9-trihydrothiopyrano[2,3-<i>b</i>]indole by 4<i>-exo-trig</i> Aryl Radical Cyclization and Rearrangement
作者:K. C. Majumdar、S. Alam
DOI:10.1021/ol061531g
日期:2006.8.1
4-(2'-Bromoaryloxymethylene)-9-methyl-2,3,9-trihydrothiopyrano[2,3-b]indoles under tri-n-butyltin hydride mediated aryl radical cyclization furnished exclusively the 4-2'-benzo(2',3'-dihydro)furo}-9-methyl-2,3,9-trihydrothiopyrano[2,3-b]indoles in excellent yield (75-80%) via 4-exo-trig cyclization, opening of the oxetene ring, and 5-endo-trig cyclization.
在三正丁基锡氢化物介导的芳基自由基环化下,4-(2'-溴芳基氧基亚甲基)-9-甲基-2,3,9-三氢硫吡喃并[2,3-b]吲哚仅提供了4- 2'-苯并( 2',3'-二氢)呋喃} -9-甲基-2,3,9-三氢硫代吡喃并[2,3-b]吲哚通过4-exo-trig环化反应,具有极好的收率(75-80%),氧杂环丁烯环和5-endo-trig环化。