N , N -1,2-Benzenedisulfonylimide, a new cyclic leaving group for the stereoselective nucleophilic substitution of amines
摘要:
We hereby report the preparation and nucleophilic substitutions of the N,N-1,2-benzenedisulfonylimide derivatives la and 2a of the chiral amines 1 and 2. The nucleophilic attack of KNO2 afforded the respective alcohols 3 and 4 with 84-90% inversion of configuration. Nucleophilic attack by the azide ion afforded the azide products 5 and 6 which were reduced to the corresponding inverted amines 1 and 2 (94-98.5% inversion). The improved leaving group ability of the N,N-1,2-benzenedisulfonylimides compared with previously reported N,N-disulfonylimides is discussed. Chiral GLC analysis of all products is summarized and the alternative chiral analysis of product 3 by C-13 NMR using heptakis(2,3,6-tri-O-methyl)-beta-cyclodextrin as a chiral solvating agent (CSA) is discussed. (C) 1998 Elsevier Science Ltd. All rights reserved.
Abfallfreie Gas/Festkörper-Diazotierung mit Stickstoffdioxid und quantitative Triazensynthese ohne Flüssigphase
摘要:
Solid diazonium nitrates (2a-j) are quantitatively obtained by reaction of crystalline anilines (1a-j) with gaseous nitrogen dioxide. Solid diazonium salts react quantitatively with dimethylamine to give the triazenes (4a-j). Wastes that are typical for the previous syntheses of these compounds in solution are avoided. Atomic force microscopic (AFM) investigations indicate long-range molecular movements due to phase rebuilding. The features thus formed are related to the known crystal structures of the starting anilines. The diazotations run to completion, because, after accumulation of product molecules, phase transformation to give the product lattices leads to crystal disintegration and thus to formation of fresh surface over and over.
PIGMENT DISPERSING AGENT, PIGMENT COMPOSITION, AND PIGMENT COLORING AGENT
申请人:DAINICHISEIKA COLOR & CHEMICALS MFG. CO., LTD.
公开号:US20200377480A1
公开(公告)日:2020-12-03
The present invention provides a pigment dispersant: that is capable of remarkably ameliorating fluidity of a liquid product, such as an ink or a paint, which contains particles of a pigment, such as a black azo pigment, in a dispersed state; that can suppress aggregation of piment particles; that prevents occurrence of foreign substances; and that is capable of producing a colored article excellent in optical density. Provided is a pigment dispersant being a compound represented by the following formula (1).
wherein R
1
and R
2
each independently represent a group obtained by eliminating one hydrogen atom from an amino group of an amine compound containing a basic nitrogen atom, and R
3
and R
4
each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or a hydroxy group.
New method for the detection of specific binding agents and their corresponding bindable substances
申请人:JANSSEN PHARMACEUTICA N.V.
公开号:EP0227173A2
公开(公告)日:1987-07-01
A method of qualitatively or quantitatively determining a component of a complex formed between at least one specific binding agent and its corresponding bindable substance. Said method comprises labelling at least one component of said complex with a marker which is easier to determine than the complex itself, whereby the marker used consists of latex particles which can be detected visually either by colour or fluorescence. Preferably the marker consists of coloured or colourable latex particles and the determination is based on the colour characteristics of the latex particles as such or, in the instance that colourable latex particles are used, on the colour characteristics of the coloured particles derived therefrom. The colour, respectively fluorescence signal is, if necessary after development, easily detected and optionally quantified. The invention further comprises coloured or colourable latex particles coated with specific binding proteins and test kits containing the same.
作者:Moritz Fink、Jannik Stäuble、Maïté Weisgerber、Erick M. Carreira
DOI:10.1021/jacs.4c01786
日期:2024.4.10
convenient syntheses of aryl azocyclopropeniums and a study of their photochemical properties. Incorporation of the smallest arene leads to pronounced redshift of the π–π* absorbance band, compared to azobenzenes. Photoisomerization under purple or green light irradiation affords Z- or E-isomers in ratios up to 94% Z or 90% E, and the switches proved stable over multiple irradiation cycles. Thermal half-lives