Convenient syntheses of unsymmetrical imidazolidines.
Unsymmetrical imidazolidines 10-14, optically active imidazolidines 20-22, and 2,3-dihydro-1H-benzimidazoles 28 and 29 were synthesized in good to excellent yields by Mannich reactions of 1,2-ethanediamines 8a-c, 18a-c, or N-methyl-1,2-benzenediamine (26a) with benzotriazole and formaldehyde, followed by the nucleophilic substitution of the benzotriazolyl group with C-nucleophiles (Grignard reagents, sodium cyanide), an S-nucleophile (benzenethiol), and a P-nucleophile (triethyl phosphite).
Katritzky
Alan R
AR
Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, USA. katritzky@chem.ufl.edu
Suzuki
Kazuyuki
K
He
Hai-Ying
HY