A mixture of 5-(9-bromo-4,5-dihydro-6-oxa-1-thia-benzo[e]azulen-2-yl)-1-(2,4-difluoro-phenyl)-1H-[1,2,4]triazole (847 mg), molybdenum hexacarbonyl (485 mg), Herman's catalyst (173 mg), tributyl phosphine tetrafluoroborate (106 mg), methanol (8 ml), THF (8 ml), and 1,8-diazabicyclo[5.4.0]undec-7-ene (0.82 mL) was heated in the microwave at 130° C. for 30 minutes. The reaction mixture was cooled, and then diluted with dichloromethane, washed with water, dried (MgSO4) and the solvent removed in vacuo. Purification using flash chromatography yielded the corresponding methyl ester, 2-[2-(2,4-difluoro-phenyl)-2H-[1,2,4]triazol-3-yl]-4,5-dihydro-6-oxa-1-thia-benzo[e]azulene-9-carboxylic acid methyl ester. Standard hydrolysis using sodium hydroxide in methanol/THF/water yielded the corresponding carboxylic acid, 2-[2-(2,4-difluoro-phenyl)-2H-[1,2,4]triazol-3-yl]-4,5-dihydro-6-oxa-1-thia-benzo[e]azulene-9-carboxylic acid.
