Synthesis of 3,5-disubstituted pyrazole derivatives with a carbamate function

One-pot reaction of 1,3-dipolar cycloaddition of aryldiazamethanes generated in situ from the sodium salts of tosylhydrazones of benzaldehyde, p-nitro-, p-methoxy-, and 3,4-dimethoxybenzaldehyde to propargyl-N-phenyl carbamate under heating led to the formation of 3,5-disubstituted pyrazoles in good yield and high regioselectivity.