Scheme 1. aSynthesis of the dialkylimidazoles containing the methoxycarbonyl group.
aReagents and conditions: (a) TrtCl, Et3N, DMF, r.t, 90–94%; (b) RC6H4CH2Br, CH3CN, 60 °C, 24 h,70–75%; (c) PhB(OH)2, Pd(OAc)2, K2CO3, acetone/H2O, 85–89%; (d) KMnO4, pyr/H2O, 100%; (e)SOCl2, MeOH, reflux, 80%; (f) SnCl2. 2H2O, EtOAc, reflux, 6 h, 86%; (g) AcOH, 5, MeOH, 4Å mol. seives, NaCNBH3, overnight, r.t, 60–70%.