Cyclopentanone → 6'-(pyridin-4-yl)-1'H-spiro[cyclopentane-1,2'-thieno[3,2-d]pyrimidin]-4'(3'H)-one

Participants

Reaction Steps

A mixture of 3-amino-5-(pyridin-4-yl)thiophene-2-carboxamide (150 mg, 0.68 mmol), p-toluenesulfonic acid monohydrate (50 mg) and cyclopentan-1-one (10 ml) in toluene (20 ml) was heated to reflux overnight. After removal of the solvent, the residue was purified by column chromatography on silica gel (MeOH: dichloromethane=1:9) to afford the title compound (140 mg, yield 72%) as an orange solid:

Provenance & Evidence