Thermal and microwave-assisted [3+2] cycloadditions between differently substituted propiolamidinium tetraphenylborates 3a–d and N-methyl-C-phenylnitrone, benzyl azide, and N-(3-azidopropyl)phthalimide were studied. The activation parameters of the [3+2] cycloaddition between alkyne 3a and benzyl azide were determined. A Diels–Alder reaction between the terminal alkyne 3a and cyclopentadiene could
Molecular structure of β-oxy-bis-acrylamides on the pathway of the dimers formation. DFT and FTIR study
作者:Tamara N. Aksamentova、Nina N. Chipanina、Mikhail V. Andreev、Irina V. Sterkhova、Dmitry V. Pavlov、Alevtina S. Medvedeva
DOI:10.1016/j.molstruc.2019.127298
日期:2020.2
QTAIM analysis. The lowrotationalbarriers about the =С–С= and =C–O– bonds in monomers provide ease of their transitions and simultaneous participation in the formation of dimers. The calculated dissociation energies of dimers depend on the structural features of the conformers and PA values of the carbonyl oxygen. The cyclic dimers with three and two intermolecular N–H⋯O Cbonds are the most stable
摘要 β-氧-双-丙烯酰胺O(CH=CHCONR1R2)2 的构象异构体及其二聚体采用NBO 和QTAIM 分析的DFT 方法计算。单体中 =С-С= 和 =C-O- 键的低旋转势垒使它们易于转变并同时参与二聚体的形成。二聚体的计算解离能取决于构象异构体的结构特征和羰基氧的 PA 值。具有三个和两个分子间 N-H⋯OC 键的环状二聚体是最稳定的。分析了孤对氮与羰基的轨道相互作用对构象异构体的质子亲和力的影响。在比较 FTIR 光谱和计算数据时,在固态和溶液中分析了化合物及其二聚体的结构。β-oxy-bis-N 的 X 射线分析,
作者:Shenghan Teng、Zhenguo Zhang、Bohan Li、Lanyang Li、Melinda Chor Li Tan、Zhenhua Jia、Teck‐Peng Loh
DOI:10.1002/anie.202311906
日期:2023.11.6
A novel type of silicon-containing alkynone reagents that target free thiols to produce the stable vinyl-sulfide linker under biocompatible conditions is reported. Besides simple aliphatic and aromatic thiols, this approach is also applicable to the labeling of thiols present in proteins, sugars and pharmaceuticals with full retention of silicon handles in most cases.