1,4-Cyclohexadiene → 2-(8-Hydroxy-2-methylimidazo[1,2-a]pyridin-3-yl)acetonitrile

Reaction equation

C([O:8][C:9]1[C:10]2[N:11]([C:15]([CH2:19][C:20]#[N:21])=[C:16]([CH3:18])[N:17]=2)[CH:12]=[CH:13][CH:14]=1)C1C=CC=CC=1.C1CC=CCC=1>[Pd].CN(C)C=O>[C:20]([CH2:19][C:15]1[N:11]2[CH:12]=[CH:13][CH:14]=[C:9]([OH:8])[C:10]2=[N:17][C:16]=1[CH3:18])#[N:21]

Participants

Procedure

8-Benzyloxy-3-cyanomethyl-2-methylimidazo[1,2-a]pyridine (40 g, 0.14 mol), 1,4-cyclohexadiene (50 g, 0.62 mol), dimethylformamide (600 ml) and palladium black (2 g) are stirred together and heated. At 45° C., asudden exotherm occurs and the temperature rises rapidly to 75°-80°. Heating is discontinued and the mixture stirred for1 hr. The catalyst is removed by filtration and the cyclohexadiene removed in vacuo. The dimethylformamide is removed in vacuo (0.1 mm) at 55°to afford 3-cyanomethyl-2-methyl-8-hydroxy imidazo[1,2-a]pyridine (27 g, 0.14 mol).