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公开(公告)号：DE2928944A1
公开(公告)日：1981-02-12
申请号：DE2928944
申请日：1979-07-18
Applicant: BASF AG
Inventor： NISSEN AXEL DIPL CHEM DR , KAIBEL GERD DIPL ING , REBAFKA WALTER DIPL CHEM DR , WOERZ OTTO DIPL CHEM DR , ARNOLD LOTHAR DIPL CHEM DR , BRAUN MANFRED
Abstract: An improved process for the preparation of higher unsaturated ketones, such as geranylacetone and farnesylacetone, by reacting a beta , gamma -unsaturated alcohol and an alkyl acetoacetate at an elevated temperature in the presence of an organic aluminum compound, with elimination, and removal, of the alcohol derived from the alkyl acetoacetate in a reactor system carrying a fractionating column. The improvement in the purity, yield, and especially space-time yield of the product is achieved by starting from an alcohol having a higher boiling point than that of the alkyl acetoacetate used, carrying out the reaction in the presence of a small amount of an inert liquid which has a boiling point between that of the alkyl acetoacetate and the alcohol to be eliminated therefrom, and ensuring that the temperature at the bottom of the fractionating column is only slightly higher than the boiling point of the added liquid, under the prevailing pressure.
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公开(公告)号：DE3114071A1
公开(公告)日：1982-10-28
申请号：DE3114071
申请日：1981-04-08
Applicant: BASF AG
Inventor： JANITSCHKE LOTHAR DIPL CHEM DR , HOFFMANN WERNER DIPL CHEM DR , ARNOLD LOTHAR DIPL CHEM DR , STROEZEL MANFRED ING GRAD , SCHEIPER HANS-JUERGEN ING GRAD
IPC: C07C45/00 , C07C45/74 , C07C49/203 , C07C67/00
Abstract: An improved process for the preparation of unsaturated ketones of the general formula I (I) where R1 is -CH3, and R2 and R3 are different and each is H or -CH3, by reacting an aldehyde of the general formula II (II) with a molar excess of acetone or methyl ethyl ketone at an elevated temperature in the presence of an aqueous alkali metal hydroxide solution, wherein (a) all the reactants are mixed thoroughly, (b) the temperature is kept at from 10 to 120 DEG C. above the boiling point of the lowest-boiling component and (c) the pressure is kept at from p to 100 bar, where p is the vapor pressure of the mixture at the reaction temperature. The products methylpseudoionone, dimethylpseudoionone, pseudoirone, methylpseudoirone and dimethylpseudoirone are useful scents and scent intermediates. In addition, pseudoionone is an important intermediate for the industrial preparation of vitamin A, and 6-methyl-hepta-3,5-dien-2-one is a sought-after aromatic.
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公开(公告)号：DE3006867A1
公开(公告)日：1981-09-03
申请号：DE3006867
申请日：1980-02-23
Applicant: BASF AG
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