oil a solution of the compound of part b 2 00 g 6 1 mmole in dry tetrahydrofuran 20 ml was stirred at 78 u00b0 and treated dropwise with n butyllithium 1 55m in hexane 4 4 ml 6 7 mmole the mixture was stirred at 78 u00b0 for one hour then treated dropwise with a solution of thiophene 2 carboxaldehyde 0 75 g 6 7 mmole in dry tetrahydrofuran 10 ml after stirring for 15 minutes saturated aqueous ammonium chloride was added and the crude product isolated by extraction with methylene chloride this material was chromatographed 85 15 hexane ethyl acetate and triturated in hexane to provide the title compound 1 90 g 86 as a white crystalline solid mp 122 u00b0 124 u00b0 a solution of the compound of part c 1 50 g 4 2 mmole in methylene chloride 90 ml was treated with pyridinium chlorochromate 2 28 g 10 6 mmole and stirred at room temperature for 1 5 hours the mixture was filtered through florisil and concentrated under vacuum to provide the crude product this was recrystallized hexane 1 chlorobutane to provide the title compound 1 17 g 79 as a white solid mp 111 u00b0 113 u00b0 a mixture of the compound of part d 0 58 g 1 6 mmole and pyridine hydrochloride 3 48 g 0 03 mole was heated at 190 u00b0 for 3 hours the cooled reaction mass was then partitioned between methylene chloride and 1 0n hydrochloric acid and.