Organic compounds -- part of the class 532-570 series – Organic compounds – Oxygen containing
Reexamination Certificate
2005-02-04
2008-03-04
Witherspoon, Sikarl A. (Department: 1621)
Organic compounds -- part of the class 532-570 series
Organic compounds
Oxygen containing
C568S494000
Reexamination Certificate
active
07339085
ABSTRACT:
The present invention relates to an improved process for preparing 2,7-dimethylocta-2,4,6-trienedial of the formula I,bya) double enol ether condensation of a butenedial bisacetal of the formula II with an enol ether of the formula III, in the presence of a Lewis acid catalyst to give a condensation product of the formula IV, where the radicals R1and R2in formulae II to IV are independently of one another C1-C6-alkyl;b) hydrolysis of the acetal groups of IV by adding an aqueous acid to form the dialdehyde of the formula V;d) crystallization of I from the reaction mixture,Wherein process steps a) to d) are carried out in the presence of an inert, water-immiscible organic solvent.
REFERENCES:
patent: 5338888 (1994-08-01), Paust et al.
patent: 5886196 (1999-03-01), Fürbringer
patent: 321106 (1957-04-01), None
patent: 0 784 042 (1997-07-01), None
Britton, G. et al., Ed., “Carotenoids”, vol. 2: Synthesis, (1996) pp. 301-302.
Britton, G. et al., Ed., “Carotenoids”, vol. 2: Synthesis, (1996) pp. 117-118.
Makin, S. M. et al., “Chemistry of Unsaturated Ethers, XVIII. Synthesis of Unsaturated Dialdehydes and Their Derivatives”, J. Gen. Chem, USSR 34 (1964), pp. 64-68.
Ernst Hansgeorg
Henrich Klaus
Keller Andreas
BASF - Aktiengesellschaft
Connolly Bove & Lodge & Hutz LLP
Witherspoon Sikarl A.
LandOfFree
Method for producing 2,7-dimethyl-octa-2,4,6-trienedial does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for producing 2,7-dimethyl-octa-2,4,6-trienedial, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for producing 2,7-dimethyl-octa-2,4,6-trienedial will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3980806