METHOD FOR REGIOSELECTIVELY PREPARING VARIOUS PYRAZOLES USING 2-ACYL-3-AMINO-2-ALKENOATE AND HYDRAZINE

摘要

PURPOSE: A method for preparing novel pyrazole using 2-acyl-3-amino-2-alkenoate is provide to obtain various pyrazoles with high yield from 2-acyl-3-amino-2-alkenoate and hydrazine.;CONSTITUTION: A pyrazole of chemical formula 3 is prepared by reacting hydrazine of chemical formula 2 with 2-acyl-3-amino-2-alkenoate of chemical formula 1. In chemical formulas 1, 2, and 3: R1 and R3 are independently alkyl group of C1-C10, cycloalkyl group of C3-C10, or aryl group; R2 is alkyl group of C1-C10; R4 is hydrogen, alkyl group of C1-C10, cycloalkyl group or aryl group of C3-C10. The reaction is performed under the presence of acid catalyst. The acid catalyst is sulfuric acid, hydrochloric acid, nitric acid, toluene sulfonic acid or acetic acid.;COPYRIGHT KIPO 2010