Synthesis of Novel Trisubstituted Imidazolines

Abstract

Imidazolines substituted at the 1- and either the 4-, or 5-position with phenyl and at the 2-position with alkyl or phenyl have been prepared in racemic form. They appear to be fairly stable compounds and potentially useful as scaffolds in medicinal chemistry.

Key words

dihydroimidazole - imidazoline - reductive amination - ring-closure - acylation

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2

Evidence for acyl migration comes mainly from ^¹H NMR spectra of isolated 6. In particular, two broad singlets of D₂O-exchangeable protons were observed rather than the one singlet integrating to 2 H expected for amide 8.