Prepackaged Ramberg–Bäcklund reagents: useful tools for organic synthesis
作者:Eric Block、Hak Rim Jeon、David Putman、Shao-Zhong Zhang
DOI:10.1016/j.tet.2004.06.032
日期:2004.8
synthesis and reactions of several α,β-unsaturated chloromethyl sulfones is presented, for example [(chloromethyl)sulfonyl]-1,3-propadiene (4), [(chloromethyl)sulfonyl]ethene (5), [(dichloromethyl)sulfonyl]ethene (6) and (E,Z)-1,2-bis[(chloromethyl)sulfonyl]ethene (7). These compounds serve as ‘prepackaged’ Ramberg–Bäcklund reagents, which following an appropriate first step, such as Diels–Alder addition
Photochemical transformations. 33. Some studies of the photorearrangements of dibenzobarrelenes. A novel excitation-transfer relay mechanism
作者:Stanley J. Cristol、Russell L. Kaufman、Sumittada Malasanta Opitz、Wojciech Szalecki、Thomas H. Bindel
DOI:10.1021/ja00348a044
日期:1983.5
The regioselectivity of the di-..pi..-methane rearrangements did not vary with sensitizer, although the quantum yields did. The lack of depedence of product ratio upon sensitizer suggests that the product-determining step occurs after excitation transfer, rather than during it or in an exciplex containing tripletsensitizer and reactant.
Lasne, Marie-Claire; Ripoll, Jean-Louis, Bulletin de la Societe Chimique de France, 1981, vol. <II> 2, # 9-10, p. 340 - 344
作者:Lasne, Marie-Claire、Ripoll, Jean-Louis
DOI:——
日期:——
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.