Electronic structures of acyl nitrites and nitrates
作者:Xiaoqing Zeng、Li Yao、Weigang Wang、Fengyi Liu、Qiao Sun、Maofa Ge、Zheng Sun、Jianping Zhang、Dianxun Wang
DOI:10.1016/j.saa.2005.09.003
日期:2006.7
vibrational frequency about 1750 and 1820 cm(-1) reflected on the first band, respectively, for acyl nitrites and nitrate. Comparing with the calculated energies, it can be concluded that the syn conformers with Cs overall symmetry, a planar CC(O)ONO skeleton in nitrites, and a planar CC(O)ON skeleton in nitrates, respectively, are the most stable in the gas phase.
A new type of the dinitrogen pentoxide–acid interaction
作者:Victor P. Zelenov、Sergey S. Bukalov、Alexander N. Subbotin
DOI:10.1016/j.mencom.2017.07.011
日期:2017.7
solution in trifluoroacetic acid simultaneously has features of both known types of its interaction with acids, viz . with weak and strong acids. It partially reacts with CF 3 COOH to give the covalent trifluoroacetyl nitrate and nitricacid, however the major part of N 2 O 5 exists in the covalent form in solution to concurrently produce nitronium ions due to the presence of HNO 3 . Quantum chemical
在三氟乙酸中的五氧化二氮溶液同时具有与酸相互作用的两种已知类型的特征,即。用弱酸和强酸。它与CF 3 COOH部分反应,生成共价的三氟乙酰硝酸硝酸盐和硝酸,但是由于HNO 3的存在,N 2 O 5的大部分以共价形式存在于溶液中,从而同时产生硝基离子。量子化学计算证实了CF 3 COOHN 2 O 5相互作用的平衡性质。
Selective O- and N-nitration of steroids fused to the pyrazole ring
作者:A. Kh. Shakhnes、I. L. Dalinger、A. S. Shashkov、E. I. Chernoburova、M. A. Shchetinina、I. V. Zavarzin
DOI:10.1007/s11172-018-2308-z
日期:2018.10
methods for O- and N-nitration of steroids fused to the pyrazole ring were developed. The nitrating agents were acetyl, propionyl, and trifluoroacetyl nitrates generated from carboxylic acid anhydrides and either copper nitrate or nitric acid. Depending on the reaction conditions, the developed methods allow both selective nitration at the pyrazole nitrogen atom leaving intact the hydroxy group of steroid
investigates. A stable 2′-O-triflyl derivative, that of N-nitro-3′,5′-O-(tetraisopropyldisiloxane-1,3-diyl)uridine, has been isolated for the first time; by contrast to its congeners, it does not give cyclonicleoside-like intermediates. Nucleophilic attacks on this substrate lead to 2′ß-substituted nucleosides rather than the usual 2′α epimers. 3′-O-Triflyl N-nitro derivatives behave similarly. Several