1,5-Diazabicyclo(4.3.0)non-5-ene → methyl 8-oxo-9-phenyl-8H-pyrido[1,2-d]thieno[2,3-f][1,4]thiazepin-11-carboxylate

Participants

Reaction Steps

ba) 6.05 g of methyl 5-chloro-5,6-dihydro-8-oxo-9-phenyl-8H-pyrido[1,2-d]thieno[2,3-f][1,4]thiazepin-11-carboxylate were suspended in 60 ml of dimethyl sulfoxide. 3.6 ml of 1,5-diazabicyclo[4.3.0]non-5-ene were added, whereupon the mixture was heated to 70°-75° in order to complete the reaction. The mixture was then cooled to room temperature, whereby crystals separated. The mixture was poured into 300 ml of water, and the crystals were removed by filtration and washed with water. The still moist crystals were dissolved in chloroform. The solution was dried over sodium sulfate, filtered and evaporated in vacuo. After chromatography on silica gel, there was obtained methyl 8-oxo-9-phenyl-8H-pyrido[1,2-d]thieno[2,3-f][1,4]thiazepin-11-carboxylate as yellow crystals which were recrystallized from toluene. The product then has a m.p. of 207°-210°.

Provenance & Evidence