Nitrodeiodination of Polyiodopyrazoles

Abstract

Polynitropyrazoles such as 3,4‐dinitro‐1H‐pyrazole (9), 3,4,5‐trinitro‐1H‐pyrazole (10), 1‐methyl‐3,4‐dinitropyrazole (8) and 1‐methyl‐3,4,5‐trinitropyrazole (3) have been synthesized in good yields adopting iodination route for the first time.

Solvent Free Microwave Assisted Isomerization of N‐Nitropyrazoles

“…3(5),4-Dinitropyrazole (2c), 3,5-dinitropyrazole (2c), and 3,4,5-trinitropyrazole (2j) are acidic in nature due to the presence of hydrogen in the 1position. The presence of CH 3 and NH 2 groups in the 1-position of C-nitropyrazoles is known to increases the stability and thus 1-methyl-3,4,5-trinitropyrazole (MTNP) and 1amino-3,4,5-trinitropyrazole (ATNP) are presenting a very high thermal stability [3,16].…”

“…Grimmett et al [12][13][14] synthesized 1-methyl-4-nitropyrazole and 1-methyl-3,4-dinitropyrazole from 1-methylpyrazole refluxing in nitric acid-sulfuric acid mixture for 18 h. Katritzky et al [15] nitrated pyrazole, 1-methylpyrazole, and 3,5-dimethylpyrazole into the corresponding 3,4-dinitropyrazole and 1-methyl-3,4-dinitropyrazole and 3,5-dimethyl-4-nitropyrazole respectively in moderate yields using nitric acidtrifluoroacetic anhydride at room temperature. We have obtained 3,4-dinitropyrazole and 3,4,5-trinitropyrazole in higher yields from 3,4-diiodopyrazole and 3,4,5-triiodopyrazole, respectively, using fuming nitric acid and nitric acidsulfuric acid mixture [16]. Although C-dinitropyrazoles are formed quantitatively and in some instances denitration of N-nitropyrazoles during thermal isomerization is observed.…”

A Simple and Environmentally Benign Nitration of Pyrazoles by Impregnated Bismuth Nitrate

“…Nitropyrazoles are structural units found in biologically active compounds (cholesterol lowering, anti‐inflammatory, anti‐cancer, anti‐depressant, and anti‐psychotic agents), dyestuffs, and explosives . The presence of nitro group in the pyrazole ring considerably enlarges the possibility of functionalization of various types of biologically active compounds.…”

A DFT study on the structure‐property relationship of aminonitropyrazole‐2‐oxides

“…3,4,5-Trinitro-1H-pyrazole (TNP) is nonhygroscopic, weakly acidic, insensitive and exceptionally stable all C-nitrated compound [9][10][11][12][13][14]. The heat of decomposition of TNP is 255 J/g, which is extremely low to be an explosive [9,11]. The substitution of labile hydrogen of TNP by NO 2 , NH 2 , and CH 3 groups enhanced the performance and chemical stability [9,11,15].…”

“…The heat of decomposition of TNP is 255 J/g, which is extremely low to be an explosive [9,11]. The substitution of labile hydrogen of TNP by NO 2 , NH 2 , and CH 3 groups enhanced the performance and chemical stability [9,11,15]. Li et al [16] studied NO 2 , NH 2 , NF 2 , and N 3 substituted pyrazoles and suggested for their synthesis as potential compounds for low vulnerable applications.…”