Diels−Alder Reactions with 2-(Arylsulfinyl)-1,4-benzoquinones: Effect of Aryl Substitution on Reactivity, Chemoselectivity, and π-Facial Diastereoselectivity
作者:M. Carmen Carreño、José L. García Ruano、Antonio Urbano、Cynthia Z. Remor、Yolanda Arroyo
DOI:10.1021/jo9913107
日期:2000.1.1
Eu(fod)(3)- or BF(3).OEt(2)-catalyzed conditions. The synthesis of endo-adduct [4aS,5S,8R,8aR,SS]-9d resulting from cycloaddition on the substituted C(2)-C(3) double bond was achieved in a chemo- and diastereoselective way from quinone 1d in the presence of ZnBr(2). The reactivity and selectivity of the process proved to be dependent on the electron density of the arylsulfinyl group.
Diastereoselective Michael Additions of <i>N</i>-Boc-2-(<i>tert</i>-butyldimethylsiloxy)pyrrole to 2-(Arylsulfinyl)-1,4-benzoquinones
作者:Yolanda Arroyo、Mónica de Paz、Justo F. Rodríguez、M. Ascensión Sanz-Tejedor、José L. García Ruano
DOI:10.1021/jo016239v
日期:2002.8.1
obtained. The latter products result from a tandem process involving the Michaelreaction followed by an intramolecular cyclization of the intermediates 3 and 4, the first step being hardly stereoselective. Reactions catalyzed by Eu(fod)(3) evolved in a highly stereoselective manner yielding the products 3 or 5 depending on the electronic density of the arylsulfinyl group.