Potassium Hydroxide → 10-Methoxy-4H-benzo[4,5]cyclohepta[1,2-b]thiophen-4-one
Reaction equation
[OH-].[K+].Br[CH:4]1[CH:13]([O:14][CH3:15])[C:9]2[S:10][CH:11]=[CH:12][C:8]=2[C:7](=[O:16])[C:6]2[CH:17]=[CH:18][CH:19]=[CH:20][C:5]1=2>CO>[CH3:15][O:14][C:13]1[C:9]2[S:10][CH:11]=[CH:12][C:8]=2[C:7](=[O:16])[C:6]2[CH:17]=[CH:18][CH:19]=[CH:20][C:5]=2[CH:4]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
9 g of potassium hydroxide are added to a solution of 17.5 g of 9-bromo-9,10-dihydro-10-methoxy-4H-benzo[4,5]cyclohepta[1,2-b]thiophen-4-one in 400 cc of methanol, and the solution is boiled at reflux for 6 hours. After cooling to 0°-5°, the precipitated crystalline material is filtered off and recrystallized from methanol. The pure 10-methoxy-4H-benzo[4,5] cyclohepta[1,2-b]thiophen-4-one, having a M.P. of 164°-166°, is obtained in this manner. Microanalysis agrees with the formula C14H10O2S. The structure was ascertained with the nuclear magnetic resonance and mass spectrograph spectra.