924-16-3Relevant articles and documents
Versatile new reagent for nitrosation under mild conditions
Galloway, Jordan D.,Sarabia, Cristian,Fettinger, James C.,Hratchian, Hrant P.,Baxter, Ryan D.
supporting information, p. 3253 - 3258 (2021/05/06)
Here we report a new chemical reagent for transnitrosation under mild experimental conditions. This new reagent is stable to air and moisture across a broad range of temperatures and is effective for transnitrosation in multiple solvents. Compared with traditional nitrosation methods, our reagent shows high functional group tolerance for substrates that are susceptible to oxidation or reversible transnitrosation. Several challenging nitroso compounds are accessed here for the first time, including 15N isotopologues. X-ray data confirm that two rotational isomers of the reagent are configurationally stable at room temperature, although only one isomer is effective for transnitrosation. Computational analysis describes the energetics of rotamer interconversion, including interesting geometry-dependent hybridization effects.
In situ generated amine as a Lewis base catalyst in the reaction of 3,7-dinitro-1,3,5,7-tetraazabicyclo[3.3.1]nonane in nitric acid: Experimental and DFT study
Zhang, Yu,Chi, Guoli,He, Ying,Xu, Zishuai,Zhang, Luyao,Luo, Jun,Zhou, Baojing
supporting information, (2019/04/08)
The problem how ammonium nitrate affects the nitrolysis of 3,7-dinitro-1,3,5,7-tetraazabicyclo[3.3.1]nonane (DPT) in nitric acid to prepare 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX) has puzzled chemists for decades. In this paper, experimental work and theoretical calculation are described to investigate the long-standing challenge. The experiment results showed that ammonium nitrate or alkylammonium chlorides were in favor of the formation of 1-nitroso-3,5,7-trinitro-1,3,5,7-tetraazacyclooctane (MNX) but hindered the conversion of MNX to HMX. A plausible catalytic mechanism was proposed. In which ammonia or amines, in situ generated from the unfavorable balance with their salts, act as Lewis base catalysts. At the same time, the DFT computation results reveal that rigid bicyclic transition states established with 1-hydroxymethyl-3,5,7-trinitro-1,3,5,7-tetraazacyclooctane, ammonia (or amines) and three water molecules lead to very low activation energies. Then, a novel process for the preparation of MNX with excellent yield up to 78.5% was developed, which is free of the use of NaNO2 or N2O4 as nitroso resources.
A combined experimental and DFT mechanistic study for the unexpected nitrosolysis of: N -hydroxymethyldialkylamines in fuming nitric acid
Zhang, Yu,Zou, Po,Han, Yingbin,Geng, Yongliang,Luo, Jun,Zhou, Baojing
, p. 19310 - 19316 (2018/05/31)
The reaction of dimorpholinomethane in fuming HNO3 was investigated. Interestingly, the major product was identified as N-nitrosomorpholine and a key intermediate N-hydroxymethylmorpholine was detected during the reaction by 1H-NMR tracking which indicates that the reaction proceeds via an unexpected nitrosolysis process. A plausible nitrosolysis mechanism for N-hydroxymethyldialkylamine in fuming nitric acid involving a HNO3 redox reaction is proposed, which is supported by both experimental results and density functional theory (DFT) calculations. The effects of ammonium nitrate and water on the nitrosolysis were studied using different ammonium salts as additives and varying water content, respectively. Observations show the key role of ammonium ions and a small amount of water in promoting the nitrosolysis reaction. Furthermore, DFT calculations reveal an essential point that ammonia, merged from the decomposition of the ammonium salts, acts as a Lewis base catalyst, and the hydroxymethyl group of the substrate participates in a hydrogen-bonding interaction with the NH3 and H2O molecules.