摘要:
Improvement in the process for preparing biaryl compounds via coupling of an arylamine with an arene in the presence of a nitrite, an acid and copper metal or a derivative thereof; the improvement is consisting in adding to the reaction mixture a trialkylorthoformate. The process may be used for preparing drugs such as Flurbiprofen and Xenbucin or intermediate compounds particularly useful for preparing Flurbiprofen, Flufenisal, Chlordimorin, Xenbucin, Xenysalate, Xenyhexenic acid and the like.
摘要:
Preparation of sorbic acid from precursors by contact with acid catalysts is improved by utilizing crystallization to separate sorbic acid during the preparation.
摘要:
A method of converting alkanoic acids, such as isobutyric acid, to alpha-beta unsaturated acids, such as methacrylic acid and which exhibits a higher degree of selectivity than those vapor phase oxydehydration methods heretofore known to the art comprises employing a Dawson structure phosphomolybdic acid as the catalyst.
摘要:
A process for the preparation of a compound of the general formula in which each of X 1 and X 2 independently represents a fluorine, chlorine or bromine atom, which comprises reacting a compound of the general formula in which X 1 and X 2 have then meanings given above and X 3 represents a chlorine, bromine or iodine atom, with a compound of the general formula PHal 3 in which each Hal independently represents a chlorine or bromine atom, in the presence of zinc.
摘要:
Gegenstand der Erfindung sind neue, 2,6-disubstituierte 4-Hydroxybenzoesäuren und deren Ester sowie ein Verfahren zu deren Herstellung. Bei diesem Verfahren werden Cyclohexenoncarbonsäuren bzw. deren Ester in der Flüssigphase bei Temperaturen zwischen 140 und 350°C an einem Katalysator dehydriert, der Edelmetalle der 8. Nebengruppe enthält.
摘要:
Methacrylic acid is produced by oxidative dehydrogenation of isobutyric acid in vapor phase in the presence of a lithium salt of a heteropolyacid or a reduced form of the heteropolyacid.