Remote stereocontrol by the sulfinyl group. Diels-Alder reaction of cyclopentadiene with substituted (S)-[2-(p-tolylsulfinyl)styrenes and (S)-[2-(p-tolylsulfinyl)phenyl] vinyl ketones

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• 作者：M. Carmen Maestro^a ; ^{carmen.maestro@uam.es} ; José ; Antonio Ferná ; ndez-Salas^a ; José ; L. Garcí ; a Ruano^a ; Oney O. Ramí ; rez-Rodrí ; guez^a ; ^b ; Ramiro Araya-Maturana^b
• 关键词：Remote asymmetric induction ; Homochiral sulfoxide ; Asymmetric Diels&ndash ; Alder ; Chiral styrene ; Chiral enone ; Furan conjugated addition
• 刊名：Tetrahedron
• 出版年：2012
• 期刊代码：107_00404020
• 类别：ch
• 出版时间：3 June, 2012
• 卷：68
• 期：22
• 页码：4129-4137
• 文件大小：816 K

摘要

The ability of a homochiral sulfinyl group at the dienophile to act as a remote stereocontrol inductor in the Diels-Alder reaction with cyclopentadiene has been evaluated. High pressure conditions were required for the reactions of (S)-2-(p-tolylsulfinyl)styrenes 3-5 (E-1,2-disubstituted double bond) and 6-8 (1,1-disubstituted double bond). A good facial selectivity and total endo selectivity were attained with 1,1-disubstitued dienophiles, though the 1,2-disubstituted ones afforded poorer results. In contrast, (S)-[2-(p-tolylsulfinyl)phenyl] vinyl ketones 9-11 reacted readily at low temperature (鈭?0聽掳C) with complete endo selectivity and high facial selectivity in the presence of Yb(OTf)₃ as a chelating reagent of sulfinyl and carbonyl oxygen atoms. Concerning furan reactions, 尾-trifluoromethyl enone 14 afforded Diels-Alder adducts with high facial selectivity in the presence of the Lewis acid, but 尾-non-substituted enones 9 and 12 yielded products of furan conjugate addition to the double bond.