m-Chloroperbenzoic acid → 3-Chlorobenzoic Acid

Participants

Reaction Steps

m-CPBA (14 g, 62.47 mmol based on 77% purity) was dried in vacuum until vacuum reached 10 mTorr. Anhydrous methylene chloride (100 mL) was added to dissolve m-CPBA. Me(EtO)2SiCH═CH2 (10 g, 62.5 mmol) was added to the clear solution of m-CPBA in CH2Cl2. No visual changes immediately occurred. The white precipitate of m-ClC6H4COOH formed within 2 hours. The reaction mixture was reduced in volume under vacuum (about 75 mL of CH2Cl2 were removed). Pentane (50 mL) was added and then the mixture was filtered. Low boiling point volatiles were removed in vacuum. The mixture of unreacted Me(EtO)2SiCH═CH2 (10%) and the product (90%) was isolated under vacuum distillation. Second distillation yielded high purity oxirane. Yield: 50%. Boiling point: 30° C. at 0.2 Torr. Mass spectrum: (EI, %): m/z 176 (M+, 1), 161 (M+-Me, 10), 133 (M+-CHCH2O, 100). 1H NMR (C6D6): δ 3.76–3.64 (m, 4H, SiOCH2CH3), 2.59–2.5 (m, 2H, SiCHCH2), 2.08–2.05 (m, 1H, SiCHCH2), 1.17–1.07 (m, 6H, SiOCH2CH3), 0.07 (s, 3H, SiCH3). 13C NMR: (C6D6) δ 59.15 (SiOCH2CH3), 44.07 (SiCHCH2), 18.91 (SiOCH2CH3), −6.25 (SiCH3).

Provenance & Evidence