Potassium Chloride → HCID 86647120, compound

Participants

Reaction Steps

To a solution of 557 mg of an isomeric mixture of methyl 5-(6-chloro-1H-imidazo[4,5-c]pyridin-1-yl)-3-hydroxythiophene-2-carboxylate and methyl 5-(6-chloro-3H-imidazo[4,5-c]pyridin-3-yl)-3-hydroxythiophene-2-carboxylate (example C2) in 25 ml anhydrous N,N-dimethylformamide were added 248 mg K2CO3 and 428 mg 1-(bromomethyl)-2-(trifluoromethyl)benzene under a nitrogen atmosphere. The reaction mixture was stirred for 12 h at room temperature, poured into 500 ml of ice water, then 40 ml of a saturated solution of KCl were added and the mixture was allowed to stand for 12 h at 0° C. The resulting solid was filtered and washed with water. The filter cake was dissolved in dichloromethane, the organic layer was washed with water, dried with MgSO4 and concentrated under vacuum. The isomeric mixture was separated and purified by flash chromatography [(Silicagel, hexane/ethylacetate (7/3 v/v)]. The separated isomers were crystallized from dichloromethane/hexane to yield compound B3a and compound B3b. The structural assignment of the regioisomers was unequivocally established by two-dimensional 1H NMR experiments (NOESY, COSY).

Provenance & Evidence