An NHC‐Stabilised Phosphinidene for Catalytic Formylation: A DFT‐Guided Approach
作者:P. Sreejyothi、Kalishankar Bhattacharyya、Shiv Kumar、Pradip Kumar Hota、Ayan Datta、Swadhin K. Mandal
DOI:10.1002/chem.202101202
日期:2021.8.11
In recent years, the applications of low-valent main group compounds have gained momentum in the field of catalysis. Owing to the accessibility of two lonepairs of electrons, NHC-stabilised phosphinidenes have been found to be excellent Lewis bases; however, they cannot yet be used as catalysts. Herein, an NHC-stabilised phosphinidene, 1,3-dimethyl-2-(phenylphosphanylidene)-2,3-dihydro-1H imidazole
近年来,低价主族化合物在催化领域的应用得到了蓬勃发展。由于两个孤对电子的可及性,已发现 NHC 稳定的膦亚基是极好的路易斯碱;然而,它们还不能用作催化剂。在此,报道了一种 NHC 稳定的膦亚基,1,3-二甲基-2-(苯基亚膦基)-2,3-二氢-1 H咪唑 (1),用于活化 CO 2。对 CO 2活化的仔细检查通过 DFT 计算以及本征键轨道分析的过程表明,膦亚基通过两个苯环之间的非共价 π-π 相互作用与苯基硅烷相关联,这激活了 Si-H 键,促进了氢化物转移到 CO 2分子。详细的 DFT 研究与光谱实验相结合,以了解 CO 2活化的机制及其催化还原官能化,导致一系列化学惰性伯酰胺在温和反应条件下甲酰化。
Metal-Free Synthesis of Imido Derivatives by Direct Oxidation of α-Amido Sulfones
Oxidation of α-amidoaryl sulfones with m-chloroperoxybenzoic acid under mild conditions readily provides the corresponding imides in satisfactory yields. The overall process probably involves formation of an N-acyliminium ion intermediate, which by attack of the peroxyacid anion generates the final imidoderivatives.
Designing a Cr-catalyst bearing redox non-innocent phenalenyl-based ligand towards hydrosilylative CO<sub>2</sub> functionalization
作者:Soumi Chakraborty、Arpan Das、Jasimuddin Ahmed、Sayani Barman、Swadhin K. Mandal
DOI:10.1039/d0cc05348a
日期:——
A Cr(iii)-complex bearing a redox non-innocent ligand initiates SET mediated silylative functionalization of CO2.
一种携带氧化还原非无辜配体的Cr(iii)络合物引发了SET介导的CO2硅基官能化反应。
NOVEL SEMI-SYNTHETIC GLYCOPEPTIDES AS ANTIBACTERIAL AGENTS
申请人:Chu Daniel
公开号:US20120252741A1
公开(公告)日:2012-10-04
Provided herein are semi-synthetic glycopeptides having antibacterial activity. The semi-synthetic glycopeptides described herein are made by chemical modification of a glycopeptide by hydrolyzing the disaccharide moiety of the amino acid-4 of the parent glycopeptide in acidic medium to give the amino acid-4 monosaccharide; conversion of the monosaccharide to the amino-sugar derivative; acylation of the amino substituent on the amino acid-4 amino-substituted sugar moiety with certain acyl groups; conversion of the amide group in amino acid-3 to various acylamide, acylsulfonamide, acylsulfonylurea derivatives; aminomethylation with substituent containing sulfonamide or acylsulfonamide group on amino acid-7 through Mannich reaction; and conversion of the acid moiety on the macrocyclic ring to certain substituted amides. Also provided herein are pharmaceutical compositions comprising the semi-synthetic glycopeptides, and methods of use of the semi-synthetic glycopeptides for the treatment and/or prophylaxis of diseases, especially bacterial infections.