Hydrogen Peroxide → HCID 69820135, compound

A 2L flask was charged with tetrahydrofuran (600 mL) and one normal aqueous sodium hydroxide (260 mL). To this solution was added 5-bromo-3-ethylsalicylaldehyde (58 g, 0.25 mol, prepared by the procedure described by S. A. Weerawarna et al., J. Het. Chem., 1991;28:1400). With good stirring, hydrogen peroxide (400 mL of 3% solution, 0.35 mol) was slowly added. After 30 minutes, tlc (silica plate eluted with hexane:ethyl acetate, 7:3) showed no more starting material. The reaction mixture was brought to a pH of ˜5.0 by addition of acetic acid. The tetrahydrofuran was removed under vacuum, then the aqueous mixture was extracted twice with 300 mL portions of methyl t-butyl ether. The ether solution was dried over magnesium sulfate, filtered, and concentrated to a dark oil (54.8 g). This material was not further purified, but used directly in the next reaction.

1. customprepared by the procedure
2. washtlc (silica plate eluted with hexane:ethyl acetate, 7:3)
3. additionThe reaction mixture was brought to a pH of ˜5.0 by addition of acetic acid
4. customThe tetrahydrofuran was removed under vacuum
5. extractionthe aqueous mixture was extracted twice with 300 mL portions of methyl t-butyl ether
6. dry with materialThe ether solution was dried over magnesium sulfate
7. filtrationfiltered
8. concentrationconcentrated to a dark oil (54.8 g)
9. customused directly in the next reaction

ORD record

ord-e11b274287174ac49e02c16e5641a9ff

Source dataset

uspto-grants-2001_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06252070B1