1.
Tetrahedron Lett
; 59(41): 3674-3677, 2018 Oct 10.
Article
in English
| MEDLINE
| ID: mdl-30449908
ABSTRACT
In the course of our studies on the chemistry of oxyallyl species we uncovered a new (3+2) cycloaddition of aza-oxyallyl systems, generated in situ from N-benzyloxy-2-chloroamides in the presence of NEt3, onto N-arylimines yielding imidazolidin-4-ones in moderate to good yields. The cycloadditions are regioselective. Computational modelling using DFT at the M062×/6-311+G** level is in support the observed regioselectivities. Although the path to the trans imidazolin-4-one is favored, the cis product is preferred by almost 8 kcal/mol and could be formed by base-catalyzed epimerization. All products were isolated by chromatography and characterized by means of their FTIR, NMR and HRMS data.