Preparation of imidazoles

A process for preparing imidazoles of the formula (I):

• ##STR30## in which R.sup.1 is (1) hydrogen;
• (2) alkyl group;
• (3) a haloalkyl group of the formula:
• Y--(CH.sub.2).sub.m -- wherein Y is chloro or bromo, and m is an integer of from 2 to 6;
• (4) an acyloxyalkyl group of the formula:
• R.sup.3 --O--(CH.sub.2).sub.n -- wherein n is an integer of from 2 to 6, and R.sup.3 is an acyl group;
• (5) a cyanoalkyl group of the formula:
• NC--(CH.sub.2).sub.p -- wherein p is an integer of from 1 to 6;
• (6) a cycloalkyl group;
• (7) a group of the formula:
• R.sup.4 --S--(CH.sub.2).sub.q -- wherein R.sup.4 is lower alkyl or phenyl group, and q is an integer of from 1 to 5;
• (8) a group of the formula:
• CF.sub.3 --(CH.sub.2).sub.r -- wherein r is an integer of from 0 to 5;
• (9) a group of the formula:
• ##STR31## wherein s is an integer of from 1 to 5;
• (10) an aralkyl group of the formula:
• ##STR32## wherein W and Z are independently hydrogen, halogen, alkyl, alkoxy, acetylamino, cyano, or nitro group, or a group:
• --COOR.sup.5 wherein R.sup.5 is lower alkyl, or W and Z, taken together, may form alkylenedioxy group, and t is an integer of from 1 to 5;
• or (11) an aryl group of the formula:
• ##STR33## wherein W and Z have the same meaning as defined above;
• R.sup.2 has the same meaning as R.sup.1 or R.sup.2 may represent a group selected from the group consisting of ##STR34## wherein R.sup.6 is hydrogen, lower alkyl, alkoxy, or phenyl, and u is an integer of from 1 to 5,
• which comprises conducting condensation among an .alpha.,.alpha.-dihaloaldehyde compound of the formula (II):
• ##STR35## in which R1 is as defined above, and X is halogen, an aldehyde compound of the formula:
• R.sup.2 --CHO in which R.sup.2 is as defined above, and aqueous ammonia.