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
作者:M. Carmen Maestro、José Antonio Fernández-Salas、José L. García Ruano、Oney O. Ramírez-Rodríguez、Ramiro Araya-Maturana
DOI:10.1016/j.tet.2012.03.112
日期:2012.6
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
在亲二烯体上的同手性亚磺酰基作为Diels-Alder与环戊二烯反应的远程立体控制诱导剂的能力已得到评估。被要求为(反应高压条件小号)-2-(p -tolylsulfinyl)苯乙烯3 - 5(Ë -1,2-二取代的双键)和6 - 8(1,1-二取代的双键)。用1,1-二取代的亲二烯物获得了良好的面部选择性和总的内在选择性,尽管1,2-二取代的亲二物物的结果较差。相反,(S)-[2-(对甲苯基亚磺酰基)苯基]乙烯基酮9– 11在作为亚磺酰基和羰基氧原子螯合剂的Yb(OTf)3的存在下,在低温(−40°C)下具有完全的内在选择性和高的面部选择性,易于反应。关于呋喃反应,在路易斯酸存在下,β-三氟甲基烯酮14可提供具有高面部选择性的Diels-Alder加合物,但是β-非取代的烯酮9和12产生了呋喃共轭物加成双键的产物。