Search results for "TRIF"

Herbizide, 2. Mitt. 2-Trifluormethylpyrimido[1,2-a]benzimidazole

1982

Aus der Kondensation von 2-Aminobenzimidazol (1) mit den Trifluormethyl-β-Diketonen 2a-f gehen die 2-Trifluormethylpyrimido[1,2-a]benzimidazole 3a-f hervor. Auffallende herbizide Wirksamkeit vermag 3a zu entfalten. Herbicides, II: 2-(Trifluoromethyl)pyrimido[1,2-a]benzimidazoles The condensation of 2-aminobenzimidazole (1) with the trifluoromethyl-β-diketones 2a-f furnishes the 2-(trifluoromethyl)pyrimido[1,2-a]benzimidazoles 3a-f. Marked herbicidal activity is exhibited by 3a.

Physicochemical Properties of New Dicationic Ether-Functionalized Low Melting Point Ammonium Salts

2010

Eleven new and one previously known but insufficiently characterized dicationic quaternary ammonium (QA) salts were synthesized and characterized. They contain an ethoxy ethyl group either in a side chain and/or as spacer of the diammonium cation and have bromide, hexafluorophosphate (PF6–), bis(trifluoromethanesulfonyl)imide (TFSI), or trifluoromethanesulfonate (TFMS) as an anion. 1H and 13C techniques, mass spectrometry, and elemental analysis together with X-ray diffraction and thermoanalytical methods were used for their characterization both in the liquid and solid state. In addition, residual water content and viscosity measurements were made for the two room temperature ionic liquid…

1978

The synthesis and polymerization of 2-cyanoethyl N-vinylcarbamate (3b) and of the corresponding 2-trimethylsilylethyl isomer 3c are reported. The homopolymers 4b and 4c, derived from 3b and 3c, could be deblocked under mild conditions (ethanolamine for 4b and trifluoroacetic acid or tetraethylammonium fluoride for 4c) with essentially 100% unmasking of the amino function. Treatment of such unmasked amino groups in a copolymer derived from N-vinyl-2-pyrrolidone and 3b with 4-{4-[bis(2-chloroethyl)amino]phenyl}butyryl chloride (13) (chlorambucil chloride) gave the corresponding amide, a potential antitumor agent. Kinetic studies showed that fluoride ion cleavage of poly(2-trimethylsilylethyl …

Refractive Indices and Deviations in Refractive Indices of Trifluoromethanesulfonate-Based Ionic Liquids in Water

2011

Refractive indices were determined for four different ionic liquid + water binary systems, from (288.15 to 338.15) K, and covering the entire composition range. The four ionic liquids used were 1-ethyl-3-methylimidazolium trifluoromethanesulfonate, 3-butyl-1-ethylimidazolium trifluoromethanesulfonate, 3-butyl-1-methylimidazolium trifluoromethanesulfonate, and 1-butyl-1-methylpyrrolidinium trifluoromethanesulfonate, all of them being completely miscible in water. From the experimental data, deviations in refractive indices, defined on a volume fraction basis, have been calculated and fitted to an extended version of the Redlich–Kister equation. The behavior of the deviations in refractive in…

Diastereoselective Synthesis of Enantioenriched Trifluoromethylated Ethylenediamines and Isoindolines Containing Two Stereogenic Carbon Centers by Nu…

2020

Fluoroform, HFC-23, is an industrial byproduct from the synthesis of polytetrafluoroethylene and is a vastly underused resource; however, its physicochemical properties have hindered progress toward synthetic uses. Herein, we describe the use of HFC-23 as a cheap trifluoromethylating agent in two reactions for the highly diastereoselective synthesis of medicinally attractive chiral amines with two stereogenic carbon centers: a base-dependent, stereodivergent nucleophilic addition to synthesize enantioenriched vicinal diamines and a tandem nucleophilic addition/aza-Michael sequence toward enantioenriched isoindolines.

ChemInform Abstract: Tandem Nucleophilic Addition-Intramolecular Aza-Michael Reaction: Facile Synthesis of Chiral Fluorinated Isoindolines.

2011

A highly stereoselective synthesis of fluorinated 1,3-disubstituted isoindolines is described. To this end, a tandem reaction consisting of a diastereoselective addition of fluorinated nucleophiles to Ellman’s N-(tert-butanesulfinyl)imines followed by an intramolecular aza-Michael reaction has been developed. This strategy allows for the construction of isoindolines bearing several degrees of fluorination (mono-, di-, or trifluoromethyl as well as heavier fluorinated groups). In the majority of all cases, the products are formed as single isomers.

N-trifluoracetyl-nylon 66 als polymeres reagenz

1979

N-Trifluoroacetyl-Nylon 66 (2) obtained by the reaction of Nylon 66 (1) with trifluoroacetic anhydride is very suitable as a polymeric reagent for the trifluoroacetylation of amines and alcohols. The advantages of 2 compared with low molecular trifluoroacetylating reagents are discussed. The selectivity against different substituted anilines and against structurally isomeric secondary amines was studied intensively by kinetic measurements.

Redistribution of total reactive nitrogen in the lowermost Arctic stratosphere during the cold winter 2015/2016

2021

During winter 2015/2016 the Arctic stratosphere was characterized by extraordinarily low temperatures in connection with the occurrence of extensive polar stratospheric clouds. From mid of December 2015 until mid of March 2016 the German research aircraft HALO (High Altitude and Long–Range Research Aircraft) was deployed to probe the lowermost stratosphere in the Arctic region within the POLSTRACC (Polar Stratosphere in a Changing Climate) mission. More than twenty flights have been conducted out of Kiruna/Sweden and Oberpfaffenhofen/Germany, covering the whole winter period. Besides total reactive nitrogen (NOy), observations of nitrous oxide, nitric acid, ozone and water were used f…

Mechanism of the oxidation of sulfides by dioxiranes: conformational mobility and transannular interaction in the oxidation of thianthrene 5-oxide.

2004

The detailed study of the oxidation of thianthrene 5-oxide (1) with methyl(trifluoromethyl)dioxirane (5b) in different solvents and in the presence of (18)O isotopic tracers is reported. Thianthrene 5-oxide (1) is a flexible molecule in solution, and this property allows for transannular interaction of the sulfoxide group with the expected zwitterionic 7 and hypervalent 10-S-4 sulfurane 9 intermediates formed in the oxidation and biases the course of the reaction toward the monooxygenation pathway.

ChemInform Abstract: E,Z-Stereodivergent Synthesis of N-Tosyl α,β-Dehydroamino Esters via a Mukaiyama-Michael Addition

2016

The stereodivergent synthesis of N-tosyl α,β-dehydroamino esters via a Mukaiyama–Michael addition is reported. The reaction of silylketene acetals with N-tosylimines derived from β,γ-unsaturated α-keto esters in dichloromethane provided the corresponding (Z)-α,β-dehydroamino esters while the (E)-isomers were obtained when the reaction was carried out in the presence of 10 mol% copper(II) triflate.