A Mn(OAc)3-Triggered Formation of Cyclopropanes from Ugi Adducts

Abstract

Ugi adducts involving malonic acid monoesters and dialkoxysubstituted aromatic aldehydes can undergo an oxidative dearomatization when treated with Mn(OAc)3 leading to the formation of fused cyclopropanes as observed in the Buchner reaction of diazo compounds

Synthesis of Tetrahydronaphthoazetidinones, 2,5‐Dioxo‐1,4‐methanobenzoazepines and 3‐Hydroxypyrrolidinones Through Copper‐Assisted Post‐Ugi Reactions

“…[3] In particular, different methodologies for the synthesis of heterocyclic systems employing the Ugi reaction followed by radical cyclizations have been described in the last few years. Among them, (1) the incorporation of additional functional groups on the Ugi adduct, e. g. xanthates, [4] alkyl iodides, [5] aryl halides, [6] alkynes [7] or activated methylene groups, [8] which favors the formation of the required radicals, and (2) the use of functionalization achieved in the Ugi reaction, both the secondary [9] or tertiary [10] amides and the peptidyl position, [11] to get these first radicals.…”