Nitropyrazoles 19.* Selective nucleophilic substitution of a nitro group in 3,4-dinitropyrazoles

摘要

N-Substituted 3,4-dinitropyrazoles, 1,5-dimethyl-3,4-dinitropyrazole and 1-methoxy-methyl-5-methyl-3,4-dinitropyrazole, undergo nucleophilic substitution when reacted with S-, O-, and N-nucleophiles. The substitution occurs regioselectively at the 3-position, affording products in good yields. Anions of N-unsubstituted 3,4-dinitropyrazoles, 1H-3(5)-methyl-4,5(3)-dinitropyrazole and 1H-4,5(3)-dinitropyrazole, also react in water with S-nucleophiles with regioselective substitution of the nitro groups in the position 3(5).