Abstract:
In a process for preparing an alkalimetalor alkaline earth metal salt of an α,β -ethylenically unsaturated carboxylic acid, a)a transition metal-alkene complex is reacted with CO 2 to give a metallalactone, b)the metallalactone is reacted with a base to give an adduct of the alkalimetal or alkaline earth metal salt of the α,β -ethylenically unsaturated carboxylic acid with the transition metal complex, and c)the adduct is reacted with an alkene to release the alkalimetalor alkaline earth metalsalt of the α,β -ethylenically unsaturated carboxylic acid and regenerate the transition metal-alkene complex. The baseis selected from alkalimetal or alkaline earth metal hydroxides and alkali metal or alkaline earth metal superbases.The alkene is, for example, ethene. The transition metal complex comprises, for example, nickel and a bidentate P,P, P,N, P,O or P,carbene ligand, such as 1,2-bis(di- tert -butylphosphino)ethane.
Abstract:
Catalytic process for preparing an α,β -ethylenically unsaturated carboxylic acid salt, wherein an alkene and carbon dioxide are reacted in the presence of a carboxylation catalyst and in the presence of a specific aryloxide to obtain the α,β -ethylenically unsaturated carboxylic acid salt, the carboxylation catalyst being a transition metal complex. The process allows for efficient preparation of α,β -ethylenically unsaturated carboxylic acid derivatives from CO 2 and an alkene.
Abstract:
Die vorliegende Erfindung betrifft ein Verfahren zur organokatalytischen ringöffnenden Polymerisation mindestens eines zur ringöffnenden Polymerisation geeigneten Monomers M, oder von Mischungen daraus, wobei in einem Schritt (i) mindestens eine N-heterocyclische Verbindung in Gegenwart mindestens einer Zerewitinoff-aktiven Verbindung Z1 einer Temperatur von mindestens 80°C für eine Dauer von mindestens 30 Sekunden ausgesetzt wird, und in einem Schritt (ii) das Monomer M zugegeben und zur Reaktion gebracht wird.
Abstract:
Catalytic process for preparing an α, β -ethylenically unsaturated carboxylic acid salt, comprising reacting an alkene and carbon dioxide in the presence of a carboxylation catalyst and releasing the α, β -ethylenically unsaturated carboxylic acid salt with a base, the carboxylation catalyst being a transition metal complex, which comprises a structurally constrained bidentate P,X ligand, wherein X is selected from the group consisting of P, N, O, and carbene, the P and X atom are separated by 2 to 4 bridging atoms, and wherein the bridging atoms are part of at least one 5- to 7-membered cyclic substructure. A further catalytic processes for preparing α, β -ethylenically unsaturated carboxylic acid derivatives from CO 2 and an alkene is provided.
Abstract:
Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung von Polyetherolen durch katalytische ringöffnende Polymerisation, wobei mindestens eine Stickstoff enthaltende cyclische Präkatalysator-Verbindung eingesetzt wird.
Abstract:
The present invention relates to a process for organocatalytic ring-opening polymerization of at least one monomer M suitable for ring-opening polymerization, or of mixtures thereof, wherein at least one N-heterocyclic compound in the presence of at least one Zerevitinov-active compound Z1 is exposed in a step (i) to a temperature of at least 80°C for a period of at least 30 seconds, and the monomer M is added and reacted in a step (ii).
Abstract:
Catalytic process for preparing an α,β-ethylenically unsaturated carboxylic acid salt, wherein an alkene and carbon dioxide are reacted in the presence of a carboxylation catalyst and in the presence of a specific aryloxide to obtain the α,β-ethylenically unsaturated carboxylic acid salt, the carboxylation catalyst being a transition metal complex. The process allows for efficient preparation of α,β-ethylenically unsaturated carboxylic acid derivatives from CO2 and an alkene.
Abstract:
The present invention relates to a method for producing polyether polyols by means of catalytic ring-opening polymerization, wherein at least one cyclic precatalyst compound containing nitrogen is used.