5-氨基吡唑与给体-受体环丙烷的 ambident 反应性。

Ambident reactivity of 5-aminopyrazoles towards donor-acceptor cyclopropanes.

机构信息

N. D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences, Leninsky pr. 47, Moscow 119334, Russian Federation.

N. M. Emanuel Institute of Biochemical Physics Russian Academy of Sciences, Kosygina 4, Moscow 119334, Russian Federation.

出版信息

Org Biomol Chem. 2022 Oct 12;20(39):7795-7802. doi: 10.1039/d2ob01490d.

DOI:10.1039/d2ob01490d

PMID:36148530

Abstract

Lewis acid-catalysed reactions of donor-acceptor cyclopropanes with 1,3-disubstituted 5-aminopyrazoles were investigated. Under catalysis with gallium(III) chloride, products of the three-membered ring opening a nucleophilic attack of the exocyclic amino group were obtained in a chemoselective manner. Oppositely, in the presence of scandium(III) triflate, products of either -alkylation or (4)-alkylation, or a mixture of both were formed. The products of the (4) alkylation were transformed in one step into tetrahydropyrazolo[3,4-]azepines that are attractive for medicinal chemistry and pharmacology.

摘要

研究了给体-受体环丙烷与 1,3-二取代 5-氨基吡唑的路易斯酸催化反应。在三氯化镓的催化下，以化学选择性方式获得了三元环开环和环外氨基亲核进攻的产物。相反，在三氟甲磺酸钪的存在下，形成了 -烷基化或 (4)-烷基化产物，或者两者的混合物。(4)烷基化产物可一步转化为四氢吡唑并[3,4-a]氮杂卓，它们在药物化学和药理学方面很有吸引力。