Abstract:
Verfahren zur Herstellung von Chloressigsäurechlorid durch (a) Umsetzung von Chloressigsäure mit Phosgen in der Flüssigphase bei einer Temperatur von 0 bis 100°C und einem Druck von 0,05 bis 0,2 MPa abs in Gegenwart eines Katalysator-Addukts aus Phosgen und einem N,N-disubstituierten Formamid der allgemeinen Formel (I) in der R 1 und R 2 unabhängig voneinander C 1 - bis C 4 -Alkyl oder R 1 und R 2 gemeinsam eine C 4 -oder C 5 -Alkylenkette bedeuten, und (b) nachfolgender Isolierung des Chloressigsäurechlorids aus dem erhaltenen Reaktionsgemisch, bei dem man in Schritt (a) das Phosgen in einem Mol-Verhältnis zur Chloressigsäure von 0,85 bis 0,99 einsetzt, und in Schritt (b) Chloressigsäurechlorid destillativ isoliert.
Abstract:
Die Erfindung betrifft ein Verfahren zur Herstellung von Onium-Salzen mit Alkyl- oder Arylsulfonat-Anionen oder Alkyl- oder Arylcarboxylat-Anionen durch Umsetzung eines Onium-Halogenids mit einem Alkyl- oder Trialkylsilylester einer Alkyl- oder Arylsulfonsäure oder einer Alkyl- oder Arylcarbonsäure oder deren Anhydride.
Abstract:
Good yields of trifluoroacetyl compounds, particularly trifluoroacetyl chloride, with short reaction times, are obtained by reaction of 1,1,1 trifluoro-2,2,2 trichloroethane with sulfur trioxide, in presence of mercury salts and addition of boron halide and/or halogenated sulphonic acid.
Abstract:
Described herein are three methods for making halogenated fluorinated ether-containing compounds using a fluorinated olefin or hexafluoropropylene oxide.
Abstract:
The present invention concerns a process for the production of a fluorinated carboxylic halide having a reduced content of impurities, a fraction of the fluorinated carboxylic halide having a reduced content of impurities, and its use in the manufacture of agriculturally and pharmaceutically active compounds or their intermediates.
Abstract:
The invention relates to a method for the manufacture of chemical compounds wherein corrosive and/ or abrasive starting compounds, catalysts, intermediates or target compounds are involved; and a suitable reactor. The method is performed in a reactor at least partially made from or at least partially coated with material which is resistant to the reaction mixture, but has a low heat transfer coefficient, and where heat is supplied by a heat exchanger from a material which has a high heat transfer coefficient and high resistance to corrosion and/or abrasion. Preferably, the reactor is coated or at least partially coated with a (chloro)fluorosubstituted material, e.g. PTFE, and the heat exchanger is preferably constructed from silicon carbide. For example, hydrochlorofluorocarbons can be manufactured using HF as a starting compound, and antimony halides as catalyst.
Abstract:
The present invention relates to a process for the preparation of dabigatran etexilate. The present invention also relates to trifluoroacetate salt of dabigatran etexilate and a process for its preparation. The present invention further relates to crystalline Form I and crystalline Form II of trifluoroacetate salt of dabigatran etexilate and processes for their preparation. The present invention further relates to a process for the preparation of pharmaceutically acceptable salts, including methanesulfonate salt, of dabigatran etexilate.
Abstract:
A process is disclosed for preparing chlorodifluoracetyl chloride from 1,1,-difluor-2,2-dichlorethylene, dichloracetyl chloride from trichlorethylene or 1,1,2,2-tetrachlorethane and trichloracetyl chloride from tetrachlorethylene. Said starting compounds are continuously reacted in the gaseous phase with oxygen to obtain a photochemical oxidation reaction, chlorine being optionally added as a sensitiser. When chlorine is added, the reaction mixture is irradiated with light with a wavelength lambda >/= 280 nm. The reaction is preferably carried out without pressure. Particularly high yields with high selectivity are reached by using doped high-pressure mercury-vapour lamps.