摘要:
A method for preparing a-(4-isobutylphenyl)propionic acid or its precursor is here disclosed which comprises the following steps (I), (II) and (III): step (I): subjecting isobutylbenzene and a polyalkylbenzene to disproportionation reaction in order to form p-isobutylethylbenzene step (II): dehydrogenating p-isobutylethylbenzene obtained in the step (I) to form p-isobutylstyrene, and step (III): the following step (IIIa) or (IIIb): step (IIIa): reacting p-isobutylstyrene obtained in the step (II) with carbon monoxide and hydrogen to prepare a-(4-isobutylphenyl)propionaldehyde, or step (IIIb): reacting p-isobutylstyrene obtained in the preceding step (II) with carbon monoxide and water or a lower alcohol to prepare a-(4-isobutylphenyl)propionic acid or its alkyl ester.
摘要:
A method for producing an aromatic polycarboxylic acid by oxidizing an aromatic feed compound having at least 3 oxidizable ring substituents, wherein, after initiation of the oxidation water from an external source is added and the reaction temperature is raised.
摘要:
A process for selectively hydroformylating a diolefin, which comprises reacting a (1-arylethenyl)-vinylbenzene with carbon monoxide and hydrogen under the conditions of 40 to 200°C in reaction temperature and 5 kg/cm2 or above in reaction pressure in the presence of a transition metal carbonylation catalyst to thereby selectively hydroformylating only the vinyl group and produce alpha-((1-arylethenyl)phenyl)-propionaldehyde. The starting material to be hydroformylated may be a mixture of the vinylbenzene with a 1,1-di(substituted aryl)ethylene not substituted by a vinyl group.
摘要:
New compounds, i.e.α-(3-(1-phenylethenyl)phenyl)propionic acid and its esters and a method for producing α-(3-benzoylphenyl)propionic acid which is prepared by oxidizing the former compound as an intermediate. The method is characterized by the easiness in operation, the low cost and the high purity of the product.
摘要:
Aromatische Carbonsäuren können aus den entsprechenden Acylaromaten oder substituierten Acylaromaten durch Oxidation mit Sauerstoff oder Luft in Gegenwart löslicher Mangankatalysatoren erhalten werden. Das Verfahren ist besonders geeignet zur Herstellung aromatischer Carbonsäuren mit an sich oxidierbaren Substituenten, beispielsweise Alkyl-Carbonsäuren, deren Substituenten bei der üblichen Ausführung der Luftoxidation ebenfalls oxidiert werden.
摘要:
An aromatic monocarboxylic acid is produced by oxidizing a benzene derivative having an alkyl group in a liquid phase with molecular oxygen or a molecular oxygen-containing gas in the presence of a heavy metal compound catalyst at a specific temperature under incorporating 0.05 to 2 times by weight of a lower aliphatic monocarboxylic acid to said benzene derivative.