$\left[Zn(OTf)_{2}\right]$-catalyzed synthesis of 2-alkynylazetidines and their ring expansion to functionalized 1,4,5,6-tetrahydropyridines

A zinc(II) triflate catalyzed reaction of beta-chloro aldimines with terminal alkynes leading to a rapid and efficient formation of 2-alkynylazetidines in good to excellent yield has been described. The catalytic hydrogenation of the 2-alkynylazetidines resulted in acyclic secondary amines by reductive cleavage of the 2-alkynylazetidine. Further, these non-activated 2-alkynylazetidines were ring expanded in a reaction with dimethyl acetylenedicarboxylate in the presence of zinc(II) triflate to give 4-alkynyltetrahydropyridines. Catalytic reduction of these 4-alkynyltetrahydropyridines led to an efficient conversion to 4-alkyltetrahydropyridine carboxylates.

Publication year:2018

Keywords:A1 Journal article

BOF-keylabel:yes

BOF-publication weight:10

CSS-citation score:1

Authors from:Higher Education

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