P-Methoxycarbonylperbenzoic Acid

Abstract

[28276-78-0] C9H8O5 (MW 196.17) InChI = 1S/C9H8O5/c1-13-8(10)6-2-4-7(5-3-6)9(11)14-12/h2-5,12H,1H3 InChIKey = ZPTDYZFKYMQWRT-UHFFFAOYSA-N (electrophilic reagent which delivers oxygen to alkenes1) Alternate Name: PMCPBA. Physical Data: white crystalline solid; dec. 125 °C. Solubility: sol ether, dioxane, CH2Cl2, CHCl3; slightly sol benzene; insol cyclohexane, CCl4. Analysis of Reagent Purity: iodometric titration. Preparative Methods: a mixture of aldehyde 1 (98% pure, 2 g) and CCl4 (50 mL) is stirred under oxygen in a glass reactor at 25 °C and irradiated with a 2 kW high-pressure mercury lamp until about 95% of the theoretical amount of oxygen is absorbed (0.5 h) (eq 1). The product, which separates as a white crystalline powder, is collected and dried (yield 2.0 g, 84%; peroxy acid content 90%); this material can be used for general oxidation reactions.1 (1) Purification: recrystallization from methanol. Handling, Storage, and Precautions: the peroxy acid 2 is as stable as m-Chloroperbenzoic Acid and shows less than 5% decomposition after storage at 10 °C for 1 year. 2 irritates nasal membranes and causes sneezing. Since the reagent is a peroxide and potentially explosive, care is required in carrying out reactions with it. During workup, check for peroxides before solvent removal. This reagent should be handled in a fume hood.