Lawesson's reagent → (+/-)-5-[2-methyl-4H-benzo[5,6]cyclohepta[1,2-d]oxazol-4-yl)-1-methyl-3,4-dihydro-4-thioxo-2(1H)-pyrimidinone

Participants

Reaction Steps

A mixture of the product from step (iii), (0.075 g) and Lawesson's reagent (0.094 g) in 1,4-dioxane (5 ml) under nitrogen was heated at reflux 16 h. The reaction mixture was partitioned between ethyl acetate and saturated brine. The organic phase was collected, dried over magnesium sulphate and solvent evaporated under reduced pressure. Purification was by flash chromatogaphy eluting with 0 to 2% ethanol in dichloromethane followed by a second column eluting with 40% ethyl acetate in toluene to give the title compound as a yellow solid.

Provenance & Evidence