Diisopropylamine → 1,2,3,4-Tetrahydro-6-[hydroxy[4-(2-pyridinyl)phenyl]methyl]-3-methyl-1-(1-methylethyl)-2,4-dioxo-thieno[2,3-d]pyrimidine-5-carboxylic acid, ethyl ester

Participants

Reaction Steps

Lithium diisopropylamide, freshly made by adding n-buthyllithium (1.1 mL, 2.5M in hexanes) to a solution of diisopropylamine (0.46 mL) in dry tetrahydrofuran under nitrogen at 0° C. and stirring for 20 min, was added to a solution of 1,2,3,4-tetrahydro-3-methyl-1-(1-methylethyl)-2,4-dioxo-thieno[2,3-d]pyrimidine-5-carboxylic acid, ethyl ester (0.7 g), 4-(2-pyridyl)benzaldehyde (0.52 g) and DMPU (057 mL) in dry tetrahydrofuran under nitrogen at −78° C. The reaction mixture was stirred at −78° C. for 4 hours then quenched with glacial acetic acid (10 mL) and allowed to reach room temperature. Water was added and the mixture was extracted with ethyl acetate (twice). The organics were washed with brine, dried over MgSO4 and concentrated under vacuum to give a brown oil which was purified by silica chromatography eluting with isohexane/ethyl acetate (1/1) to give the sub-title compound as a pale yellow foam (0.47 g).

Provenance & Evidence