Organic compounds -- part of the class 532-570 series – Organic compounds – Carboxylic acid esters
Reexamination Certificate
2005-04-05
2009-02-24
Puttlitz, Karl J (Department: 1621)
Organic compounds -- part of the class 532-570 series
Organic compounds
Carboxylic acid esters
C562S553000
Reexamination Certificate
active
07495123
ABSTRACT:
The present invention relates to a process for the efficient preparation of enantiomerically enriched beta amino acid derivatives wherein the amino group is unprotected. The product chiral beta amino acid derivatives are useful in the asymmetric synthesis of biologically active molecules. The process comprises an enantioselective hydrogenation of an amine-unprotected prochiral beta-amino acrylic acid or derivative thereof in the presence of a rhodium metal precursor complexed with a chiral mono- or bisphosphine ligand.
REFERENCES:
patent: 5563309 (1996-10-01), Togni et al.
patent: 6258979 (2001-07-01), Kagan et al.
patent: 6284925 (2001-09-01), Knochel et al.
patent: 6492544 (2002-12-01), Krimmer et al.
patent: 6699871 (2004-03-01), Edmondson et al.
patent: 7015348 (2006-03-01), Matsumura et al.
patent: 2004/0023344 (2004-02-01), Matsumura et al.
patent: 2004/0167339 (2004-08-01), Zhang
patent: 2006/0194977 (2006-08-01), Xiao et al.
patent: 1 103 536 (2001-05-01), None
patent: 1 389 901 (2004-02-01), None
patent: WO 02/40491 (2002-05-01), None
patent: WO 03/004498 (2003-01-01), None
patent: WO 2004/085378 (2004-10-01), None
Zhu, G. et al, “Highly Efficient Asymmetric Synthesis of B-Amino Acid Derivatives via Rhodium-Catalyzed Hydrogenation of B-(Acylamino)acrylates”, J. Org. Chem, vol. 64, pp. 6907-6910, 1999.
Lubell, W. et al, “Enantioselective Synthesis of B-Amino Acids Based on BINAP-Ruthenium(II) Catalyzed Hydrogenation” Tetrahedron: Asymmetry, vol. 2, No. 7, pp. 543-554, 1991.
Hsiao, Y. et al, “Highly Efficient Synthesis of B-Amino Acid Derivatives via Asymmetric Hydrogenation of Unprotected Enamines”, J. Am. Chem. Soc., vol. 126, pp. 9918-9919, 2004.
Hayashi, T. et al. “Asymmetric Synthesis Catalyzed by Chiral Ferrocenylphosphine-Transition Metal Complexes. I. Preparation of Chiral Ferrocenylphosphines” Bull. Chem. Soc. Jpn, vol. 53, pp. 1138-1151, 1980.
Armstrong, III Joseph D.
Clausen Andrew M.
Krska Shane W.
Malan Christophe
Rivera Nelo R.
Durette Philippe L.
Fitch Catherine D.
Merck & Co. , Inc.
Puttlitz Karl J
Solvias AG
LandOfFree
Process for the preparation of enantiomerically enriched... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for the preparation of enantiomerically enriched..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for the preparation of enantiomerically enriched... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-4123233