Sodium Bicarbonate → Methyl 5-(6,7-dihydro-4H-pyrano[4,3-d]thiazol-2-yl)-2,4-dimethylbenzoate

Participants

Reaction Steps

To a solution of methyl 5-carbamothioyl-2,4-dimethylbenzoate (compound 130.1, 500 mg, 2.24 mmol, 1.00 equiv) in ethanol (5 mL) was added sodium bicarbonate (396 mg, 4.71 mmol, 1.00 equiv) and 3-bromodihydro-2H-pyran-4(3H)-one (compound 1.10.1, 186 mg, 1.04 mmol, 1.00 equiv). The resulting solution was stiffed overnight at 80° C. under nitrogen. After cooling to room temperature the mixture was concentrated under reduced pressure. The residue was taken up 10 mL of water and ethyl acetate. The aqueous phase was extracted with 2×20 mL of ethyl acetate and the combined organic layers were dried (MgSO4), and concentrated under reduced pressure to yield 400 mg (56%) of the title compound as a yellow solid.

Provenance & Evidence