摘要:
Transition metals may be recovered from a salt-containing mixture containing at least one transition metal compound, salts, and organic compounds by separating from the salt-containing mixture a mixture of the transition metal compound and the salts. This mixture, together with any organic impurities, is introduced into a combustion zone, and the flue gas/salt mixture leaving the combustion zone is quenched with water. The combustion residue, containing the transition metal, is separated from the resulting quench solution, dried, and converted to fresh catalyst.
摘要:
A process for preparing malonic diesters by carbonylation of haloacetic esters and reaction with monohydric alcohols and a base in the presence of a transition metal catalyst, preferably a catalytic cobalt carbonyl complex, using a stirred reactor with one or more internal heat exchangers. The stirred reactor preferably contains a sparging stirrer.
摘要:
3-Alkoxy acrylonitriles are obtained directly from the corresponding nitriles by reaction of carbon monoxide and alcoholates followed by reaction with organic halides.
摘要:
4-alkylpyrimidine is produced by reacting formamide with a formyl methyl alkyl ketone diacetal without the addition of water at a temperature that allows removal of the 4-alkylpyrimidine from the reaction mixture by distillation. The process is readily applicable on an industrial scale and succeeds without the addition of water or ammonium chloride as a catalyst and permits the production of 4-alkylpyrimidine in good yields and excellent purities without time-consuming extraction steps.
摘要:
(Cyclo)aliphatic polyisocyanates are provided which are completely or partially blocked with malonic esters, the malonic ester containing at least one tert-butyl group. The blocked polyisocyanates may be deblocked at a reduced temperature.
摘要:
An olefin copolymer is prepared by copolymerizing ethylene, an .alpha.-olefin and, optionally a diene having non-conjugated double bonds by solution polymerization in the presence of:(a) an organoaluminum compound,(b) a vanadium compound in the oxidation state from +3 to +5, and(c) an activator in a molar ratio of from 0.5 to 100 relative to vanadium of said vanadium compound, and an activator of a 2-halomalonic ester substituted by an aromatic group and having the formula ##STR1## wherein X=F, Cl, Br or I, Ar is an aromatic radical which is unsubstituted, monosubstituted or polysubstituted by alkyl or alkoxy groups and which is bound to the central carbon atom either directly or by an intervening carbonyl group; and R.sub.1 and R.sub.2 are hydrocarbon radicals having from 1 to 20 carbon atoms.
摘要:
A process for preparing guanine, in which 2,4-diamino-5-formylamino-6-hydroxypyrimidine (DAFHP) in formic acid is reacted at superatmospheric pressure, optionally in the absence of formamide and/or in the presence of catalytic amounts of an additive which acts as a reducing agent.
摘要:
Arylacetaldehyde-dialkylacetals are prepared with high yields and selectivity from the corresponding chloromethylaromatics in the presence of hydrogen chloride acceptors and methyl carbonyl compounds as catalysts and in the presence of orthoesters as water-binding agents by hydroformylation with carbon monoxide and hydrogen.
摘要:
A process for the preparation of guanine, by reacting 2,4-diamino-5-formylamino-6-hydroxypyrimidine (DAFHP) with formic acid, in the absence of formalize. The process may be conducted with the addition of water and at reflux temperature.