公开(公告)号：JP2002114728A

公开(公告)日：2002-04-16

申请号：JP2001272755

申请日：2001-09-07

Applicant: BASF AG

Inventor： THERRE JORG ,  KAIBEL GERD ,  AQUILA WERNER DR ,  WEGNER GUNTER ,  FUCHS HARTWIG

IPC: C07C41/50 ,  C07B61/00 ,  C07C41/56 ,  C07C41/58 ,  C07C43/303

Abstract: PROBLEM TO BE SOLVED: To overcome disadvantages of the prior art and to provide a process for preparing an unsaturated acetal which is easy to regulate and can be operated in a stable manner. SOLUTION: This continuous process for preparing the unsaturated acetal of formula I (wherein, R1 to R7 are each independently hydrogen or a straight- chain or a branched, optionally substituted 1-6C alkyl group; R8 is hydrogen or a saturated or a mono- or a polyunsaturated straight-chain or branched, optionally substituted 1-12C alkyl group or a 3- to a 12-membered saturated or a mono- or a polyunsaturated carbocyclic ring) by reacting 1 mol of an aldehyde of formula II (wherein, R1 to R3 are as defined in the following formula I) with at least 1 mol of an alcohol of formula III (wherein, R5 to R8 are as defined by the following formula I) in the presence of a catalytic amount of an acid while removing water formed during the reaction, which comprises only partially reacting the reactants in a reactional column, concentrating the resultant acetal in at least two successive evaporation stages and returning the recovered reactants to the reactional column.

公开(公告)号：PT947493E

公开(公告)日：2003-03-31

申请号：PT99105126

申请日：1999-03-26

Applicant: BASF AG

Inventor： STROEZEL MANFRED ,  KAIBEL GERD ,  AQUILA WERNER ,  BROCKER FRANZ JOSEF ,  FUCHS HARTWIG ,  WEGNER GUNTER

IPC: B01J23/44 ,  B01J8/20 ,  B01J8/22 ,  B01J19/24 ,  B01J23/46 ,  C07B61/00 ,  C07C45/62 ,  C07C47/21 ,  C07C49/04

Abstract: Production of saturated carbonyl compounds (I) by selective liquid-phase hydrogenation of alpha , beta -unsaturated carbonyl compounds (II) is carried out in a packed bubble column with the product recycled and by circulating hydrogen gas. Production of saturated carbonyl compounds of formula R1-CH(R2)-CH(R3)-C(R4)=O (I) by selective liquid-phase hydrogenation of alpha , beta -unsaturated carbonyl compounds of formula R1-C(R2)=C(R3)-C(R4)=O (II) in the presence of a particulate palladium and/or rhodium catalyst and a base is carried out in a packed bubble column with the product recycled and by circulating hydrogen gas. R1 = H or an organic group; R2-R4 = H or 1-4C alkyl.

公开(公告)号：AU2003254348A1

公开(公告)日：2004-02-02

申请号：AU2003254348

申请日：2003-07-14

Applicant: BASF AG

Inventor： WEGNER GUNTER ,  FUCHS HARTWIG ,  UNVERRICHT SIGNE ,  SALDEN AXEL ,  GOBBEL HANS-GEORG

IPC: C07C45/62 ,  C07C47/21

公开(公告)号：PT992477E

公开(公告)日：2003-06-30

申请号：PT99118458

申请日：1999-09-17

Applicant: BASF AG

Inventor： THERRE JORG ,  KAIBEL GERD ,  AQUILA WERNER ,  FUCHS HARTWIG ,  WEGNER GUNTER

IPC: C07B61/00 ,  C07C41/28 ,  B01J27/16 ,  C07C43/15 ,  C07C45/37 ,  C07C45/51 ,  C07C45/54 ,  C07C45/67 ,  C07C47/21 ,  C07C49/203

Abstract: Preparation of citral (I) comprises thermal decomposition of 3-methyl-2-buten-1-al-diprenylacetal and rearrangement of obtained intermediates cis/trans-prenyl-(methyl-butadienyl)-ether (IV) and 2,4,4-trimethyl-3-formyl-1,5-hexadiene (V). (IV) and (V) are continuously distilled off and converted into (I) before or after removal of by-product prenol. Preparation of 3,7-dimethyl-2,6-octadien-1-al (citral) of formula (I) comprises: (1) thermal decomposition of 3-methyl-2-buten-1-al-diprenylacetal of formula (II) optionally in the presence of an acid catalyst to split off 3-methyl-buten-1-ol (prenol) of formula (III) and form cis/trans-prenyl-(methyl-butadienyl)-ether of formula (IV); (2) Claisen rearrangement of (IV) to give 2,4,4-trimethyl-3-formyl-1,5-hexadiene of formula (V); and (3) Cope rearrangement of (V) to form (I). The transitionally formed (IV) and (V) and the desired citral as well as the prenol (III) are continuously distilled out of the reaction mixture and (IV) and (V), before or after distillative separation of (III) and optional by-products, are subjected to rearrangement to form (I) at 100-200 degrees C.