of ether. Evaporation of the ether yielded a glassy foam, 1.4 g., which was dissolved in benzene and chromatographed on Woelm neutral alumina, activity I. Benzene eluted an oil which was crystallized and recrystallized from n-hexane, 0.6 g., m.p. 119.5-120.0°.N-Methyl-2,4,5-triphenylimidazole (XXVI). Procedure C (Table IV).-A mixture of 2,4,5-triphenylimidazole (0.5 g., 0.0017 mole) and diazomethane (0.006 mole) in 230 ml. of ether was irradiated 1 hr. with a G.E. sunlamp after standing 5 days at 5°. After evaporation of the ether and excess diazomethane, the yellow residue was chromatographed on Woelm neutral alumina, activity I. Elution with benzene afforded a white solid (0.1 g., m.p. 135-145°) which was recrystallized from n-hexane, m.p. 143.5-144.5°.N-Methyl-2-(p-tolyl)-4,5-diphenylimidazole (XXVII) was prepared by procedure C. The product was recrystallized from n-hexane, m.p. 209-215°, lit.18 m.p. 217°.The 27/-isoimidazoles were prepared by the method of Weiss23 from benzil (0.05 mole), the appropriate ketone (0.05 mole), and 40 g. of ammonium acetate in 100 ml. of acetic acid (procedure D). 2,2,4,5-Tetraphenyl-2IZ-isoimidazole (XXXII) was recrystallized from pyridine, m.p. 195-198°, lit.23 m.p. 199-201°. 2,2-Spirocyclohexane-4,5-diphenyl-2fl-isoimidazole (XXXIII) was recrystallized from aqueous pyridine, m.p. 105.5-106°, lit.23 m.p. 107-108°.2,4,4,5-Tetraphenyl-4/i-isoimidazole (XXXVI).-A dried chloroform solution of benzamidine prepared from 14.0 g. of the hydrochloride salt was refluxed for 4 hr. with 9.0 g. of diphenylbenzoylbromomethane.24 Water was removed as formed. The reaction mixture was freed of chloroform by evaporation and the brown residue was washed three times with warm dilute ammonium hydroxide. The orange residue was taken up in benzene and filtered. The evaporated benzene solution (9.2 g.) was chromatographed on alumina, and gave rise to 6.2 g. of crude material using petroleum ether (b.p. 30-60°) and benzene as eluents. Two recrystallizations from benzene-heptane gave2.5g. of impure isoimidazole, m.p. 170-177°. This sample was again chromatographed on alumina and a small amount of kyaphenine, m.p. 238-238.5°, lit.15 m.p. 232°, was removed. Recrystallization from benzene-heptane gave 1.7 g. of the isoimidazole, m.p. 177-178°. A further recrystallization from aqueous pyridine did not affect the melting point.The structural assignment for XXXVI was based on the method of synthesis, the elemental analysis (Table IV), infrared spectrum (no N-H stretching absorption), and direct comparison with the other two possible isomers, XXIV and XXXII.