N-Ethyl-5-phenylisoxazolium-3 -sulfonate

Woodward s reagent K is N-ethyl-3-phenylisoxazolium-3 -sulfonate, a zero-length cross-linking agent able to cause the condensation of carboxylates and amines to form amide bonds (Woodward et al., 1961 Woodward and Olofson, 1961). The reaction... 

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