N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky prosp., 119991 Moscow (Russian Federation); V. A. Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 32 Vavilov st., 119991 Moscow (Russian Federation).
Angew Chem Int Ed Engl. 2014 Mar 17;53(12):3187-91. doi: 10.1002/anie.201306186. Epub 2014 Feb 19.
A new type of donor-acceptor cyclopropane reactivity has been discovered. On treatment with anhydrous GaCl3 , they react as sources of even-numbered 1,2- and 1,4-dipoles instead of the classical odd-numbered 1,3-dipoles due to migration of positive charge from the benzyl center. This type of reactivity has been demonstrated for new reactions, namely, cyclodimerizations of donor-acceptor cyclopropanes that occur as [2+2]-, [3+2]-, [4+2]-, [5+2], [4+3]-, and [5+4]-annulations. The [4+2]-annulation of 2-arylcyclopropane-1,1-dicarboxylates to give polysubstituted 2-aryltetralins has been developed in a preparative version that provides exceedingly high regio- and diastereoselectivity and high yields. The strategy for selective hetero-combination of donor-acceptor cyclopropanes was also been developed. The mechanisms of the discovered reactions involving the formation of a comparatively stable 1,2-ylide intermediate have been studied.
一种新型的给体-受体环丙烷反应性已经被发现。在无水 GaCl3 的作用下，由于正电荷从苄基中心迁移，它们作为偶数 1,2-和 1,4-偶极子的来源而不是经典的奇数 1,3-偶极子反应。这种反应性已经在新的反应中得到证明，即给体-受体环丙烷的环二聚反应，发生[2+2]、[3+2]、[4+2]、[5+2]、[4+3]和[5+4]环加成。2-芳基环丙烷-1,1-二羧酸酯的[4+2]-环加成得到多取代的 2-芳基四氢萘，以制备版本进行，提供了极高的区域和立体选择性和高收率。还开发了选择性杂环加成给体-受体环丙烷的策略。已经研究了涉及形成相对稳定的 1,2-叶立德中间体的发现反应的机理。
Zotero 插件