Installation of the imidazole ring on chiral substrates via allylic substitution

Abstract

Allylic substitution of chiral allylic picolinate (1 equiv) with the copper reagents derived from 2-lithio-1-alkylimidazoles (2 equiv), CuBr·Me2S (1 equiv) and MgBr2 (3 equiv) afforded imidazole derivatives possessing a chiral allylic chain at the C2 position stereo- and regioselectively. The chiral imidazoles thus produced were transformed into [chiral imidazolium]+[NTf2]– in good yields. Similarly, the 2-pyridyl derivative with a chiral side chain was synthesized.