Title: Woodward's Reagent K
CAS Registry Number: 4156-16-5
CAS Name: 2-Ethyl-5-(3-sulfophenyl)isoxazolium inner salt
Additional Names: N-ethyl-5-phenylisoxazolium-3¢-sulfonate
Molecular Formula: C11H11NO4S
Molecular Weight: 253.27
Percent Composition: C 52.16%, H 4.38%, N 5.53%, O 25.27%, S 12.66%
Literature References: Prepd by reacting 5-phenylisoxazole with chlorosulfonic acid, followed by alkylation with triethyloxonium fluoroborate, and acid hydrolysis: Woodward et al., J. Am. Chem. Soc. 83, 1010 (1961).
Properties: Crystals, dec 207-208°. Stable. Non-hygroscopic.
Use: Peptide-bond former. |