Potassium Hydroxide → 2,3-Diphenyl-2-cyclopropene-1-carboxylic acid
Reaction equation
[C:1]1([C:7]2[CH:8]([C:16]([O:18]CC)=[O:17])[C:9]=2[C:10]2[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[OH-].[K+]>CO>[C:10]1([C:9]2[CH:8]([C:16]([OH:18])=[O:17])[C:7]=2[C:1]2[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=2)[CH:11]=[CH:12][CH:13]=[CH:14][CH:15]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
Ethyl 2,3-diphenyl-cycloprop-2-ene-1-carboxylate (1.75 g, 6.6 mol) and potassium hydroxide (1.79 g, 31.9 mmol) were dissolved in methanol (60 cm3) and heated to reflux for 5 hours. The mixture was cooled to room temperature and the solvent evaporated. The residue was partitioned between water (30 cm3) and ethyl acetate (30 cm3). The aqueous layer was separated and washed with ethyl acetate (2×30 cm3) before being acidified to pH=1 with dilute hydrochloric acid and extracted with dichloromethane (3×40 cm3). The combined dichloromethane extracts were dried (MgSO4) and evaporated to give the cyclopropene acid 1.22 g, 78%.