Thiophene → Cyclopentyl-2-thienylmethanone

Participants

Reaction Steps

A solution of 8.8 g (105 mmol, 1.2 equivs.) of thiophene and 10.0 g (88 mmol) of cyclopentanecarboxylic acid in 20 g of polyphosphoric acid was stirred at 75° C. for 2 hours. The reaction mixture was diluted with water and extracted with o-dichlorobenzene to afford 99% pure product (GC, area % analysis). The mixture was azeotropically dried by stripping a small portion of the solvent. The crude cyclopentyl 2-thienyl ketone solution was then used without purification, for the bromination step of Example 2.

Provenance & Evidence