<i>α</i>,<i>β</i>-Unsaturated <i>α</i>′-Halomethylsulfones: Prepackaged Ramberg–Bäcklund Reagents for Tandem Synthetic Processes
作者:Eric Block、Hak Rim Jeon、David Putman、Shao-Zhong Zhang
DOI:10.1080/10426500590910783
日期:2005.3.2
synthesis and reactions of several α,β-unsaturated chloromethyl sulfones are presented, for example [(chloromethyl) sulfonyl]-1,3-propadiene, [(chloromethyl) sulfonyl]ethene, [(dichloromethyl)sulfonyl]ethene and (E,Z)-1,2-bis[(chloromethyl)sulfonyl]ethene. These compounds serve as “prepackaged” Ramberg–Bäcklund reagents, which, following an appropriate first step, such as Diels–Alder addition, react
Chloromethanesulfonylethene and Dichloromethanesulfonylethene: New Reagents for Tandem Diels−Alder/Ramberg−Bäcklund Reactions
作者:Eric Block、Hak Rim Jeon、Shao-Zhong Zhang、Evgeny V. Dikarev
DOI:10.1021/ol0363523
日期:2004.2.1
Chloromethanesulfonylethene (3a) and dichloromethanesulfonylethene (3b) were prepared by oxidation of the adducts of ethylene and ClCH2SCl or Cl2CHSCl, respectively, followed by NaHCO3 dehydrochlorination. With dienes, 3a gave Diels-Alder adducts that, with base, underwent Ramberg-Backlund reaction, giving products corresponding to the adducts of the dienes and allene. Similarly, 3b gave Diels-Alder adducts that, with base in the presence of the novel chlorine source MeSO2CCl3, cleanly afforded products corresponding to the adducts of the dienes and 1,1-dichloropropa-1,2-diene.