Ferrocenyl thioketones reacted with donor–acceptor cyclopropanes in dichloromethane at room temperature in the presence of catalytic amounts of Sc(OTf)₃ yielding tetrahydrothiophene derivatives, products of formal [3 + 2]-cycloaddition reactions, in moderate to high yields. In all studied cases, dimethyl 2-arylcyclopropane dicarboxylates reacted with the corresponding aryl ferrocenyl thioketones in a completely diastereoselective manner to form single products in which (C-2)-Ar and (C-5)-ferrocenyl groups were oriented in a cis-fashion. In contrast, the same cyclopropanes underwent reaction with alkyl ferrocenyl thioketones to form nearly equal amounts of both diastereoisomeric tetrahydrothiophenes. A low selectivity was also observed in the reaction of a 2-phthalimide-derived cyclopropane with ferrocenyl phenyl thioketone.

中文翻译：

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通过二茂铁基硫酮与供体-受体环丙烷的正式[3 + 2]-环加成反应得到二茂铁基取代的四氢噻吩。


二茂铁基硫酮与供体-受体环丙烷在二氯甲烷中，在催化量的 Sc(OTf) ₃存在下，在室温下反应，产生四氢噻吩衍生物，即正式的 [3 + 2]-环加成反应的产物，产率中等至较高。在所有研究案例中，2-芳基环丙烷二甲酸二甲酯与相应的芳基二茂铁基硫酮以完全非对映选择性的方式反应，形成单一产物，其中(C-2)-Ar和(C-5)-二茂铁基基团以顺式取向。时尚。相反，相同的环丙烷与烷基二茂铁基硫酮反应形成几乎等量的两种非对映异构四氢噻吩。在 2-邻苯二甲酰亚胺衍生的环丙烷与二茂铁基苯基硫酮的反应中也观察到低选择性。