Organic compounds -- part of the class 532-570 series – Organic compounds – Nitriles
Reexamination Certificate
1999-04-22
2001-07-24
Nazario-Gonzalez, Porfirio (Department: 1621)
Organic compounds -- part of the class 532-570 series
Organic compounds
Nitriles
C556S021000, C585S425000, C562S493000, C564S080000, C564S161000, C568S592000
Reexamination Certificate
active
06265601
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a process for catalyzing cross coupling reactions (including Suzuki type cross coupling reactions) using either a dicycloalkylphenyl phosphine or dialkylphenyl phosphine ligand, which may be in the form of a metal-ligand complex or metal precursor/ligand composition. In particular, this invention relates to improved processes that use phosphines, which when combined with suitable metals or metal precursor compounds provide useful catalysts for various bond-forming reactions, including Suzuki cross-coupling reactions.
BACKGROUND OF THE INVENTION
Ancillary (or spectator) ligand-metal coordination complexes (e.g., organometallic complexes) and compositions are useful as catalysts, additives, stoichiometric reagents, monomers, solid state precursors, therapeutic reagents and drugs. Ancillary ligand-metal coordination complexes of this type can be prepared by combining an ancillary ligand with a suitable metal compound or metal precursor in a suitable solvent under suitable reaction conditions. The ancillary ligand may contain functional groups that bind to the metal center(s), remain associated with the metal center(s), and therefore provide an opportunity to modify the steric, electronic and chemical properties of the active metal center(s) of the complex.
Certain known ancillary ligand-metal complexes and compositions are catalysts for reactions such as oxidation, reduction, hydrogenation, hydrosilylation, hydrocyanation, hydroformylation, polymerization, carbonylation, isomerization, metathesis, carbon-hydrogen activation, carbon-halogen activation, cross-coupling, hetero cross-coupling, Friedel-Crafts acylation and alkylation, hydration, amination, aryl amination, dimerization, trimerization, oligomerization, Diels-Alder reactions and other transformations.
One example of the use of these types of ancillary ligand-metal complexes and compositions is in the field of cross-coupling reactions. The palladium-catalyzed cross-coupling reactions of aryl-bromides, iodides, and triflates with alkyl or aryl-boron compounds provide a general and efficient route to a wide variety of substituted alkylphenyl or biphenyl compounds, and have now been extensively developed. See Suzuki, A. in
Metal-Catalyzed Cross-Coupling Reactions;
Diederich, F., Stang, P. J., Eds.; Wiley-VCH: Weinheim, Germany, 1998; Chapter 2, pp. 49-97, which is incorporated herein by reference. See also U.S. Pat. Nos. 5,550,236 and 5,756,804, both of which are incorporated herein by reference.
However, the related palladium-catalyzed reactions of the comparatively inexpensive and readily available aryl chlorides, which represent the most attractive candidates for industrial applications of these reactions, have been underdeveloped. See Old, D. W., Wolfe, J. P., Buchwald, S. L.,
J. Am. Chem. Soc.
1998, 120, 9722-9723; and Littke, A. F., Fu, G. C.,
Angew. Chem. Int. Ed. Eng.
1998, 37, 3387-3388, which are both incorporated herein by reference. In particular, Buchwald et al. in the above referenced paper note that certain dicycloalkyl phosphine ligands are “not effective” for these palladium-catalyzed reactions.
J. Am. Chem. Soc.,
1998 at 9723. In the supplemental material to that paper, Buchwald et al. disclose that in a palladium-dicyclohexylphenylphosphine catalyzed Suzuki cross-coupling reaction, the turn over number (TON) was about 9 after 2 days, giving a turn over frequency (TOF) of about 0.19.
This invention thus surprisingly demonstrates that improved catalytic activity can indeed be obtained with the exact ligands and catalyst systems that were previously characterized as “not effective.” Compounds prepared according to the invention are suitable for use as precursors for pharmaceuticals, cosmetics, fungicides, herbicides, dyes, detergents, and polymers, including additives for these. Compounds prepared according to the invention are, in particular, valuable precursors for angiotensin II inhibitors. See
Drugs of the Future
1993, 18, 428-432.
SUMMARY OF THE INVENTION
Thus, it is an object of this invention to provide a process for the cross coupling of reactants using ligand/metal compositions and/or metal-ligand complexes. These catalyst assisted chemical transformations obtain a turn over number (TON) of at least 50 and/or a turn over frequency (TOF) of at least 5, possibly with a selectivity in the range of from about 80% to about 100%. The ligand useful in this process can be characterized by the general formula:
wherein each R
1
and R
2
is independently selected from the group consisting of alkyl, substituted alkyl, cycloalkyl and substituted cycloalkyl. Each of R
3
is independently selected from the group consisting of alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heteroalkyl, heterocycloalkyl, substituted heterocycloalkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, silyl, amino, nitro, ester, acid, alkoxy, aryloxy, hydroxy, transition metals, COOH, SO
3
G (G=Na, K, H, etc.) and combinations thereof; a is 0, 1 or 2 such that R
3
, when present, occupies either the para position or the two meta positions. Each of R
4
is independently selected from the group consisting of alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, heteroalkyl, heterocycloalkyl, substituted heterocycloalkyl, heteroaryl, substituted heteroaryl, silyl, amino, nitro, ester, acid, alkoxy, aryloxy, hydroxy, transition metals, COOH, SO
3
G (G=Na, K, H, etc.) and combinations thereof; b is 0, 1 or 2, such that when R
4
is present, it occupies either one or two ortho positions.
The ligands are added to a metal precursor to provide a catalytic composition or metal-ligand complex. And, it is an object of this invention to provide improved processes using such compositions (i.e., comprising the ligand and a metal precursor) or metal complexes. The suitable metal or metal precursor compound can be of the form ML
n
, where the composition has catalytic properties. Also, the ligands can be coordinated with a metal precursor to form metal-ligand complexes, which may be catalysts. Here, M is a transition metal selected from the group consisting of Groups 5, 6, 7, 8, 9 and 10 of the Periodic Table of Elements, preferably Pd, Ni, Ru, Rh, Pt, Co, Ir and Fe; L is independently each occurrence, a neutral and/or charged ligand; and n is a number 0, 1, 2, 3, 4, and 5, depending on M. M is most preferably Pd or Ni.
Another aspect of this invention is the chemical transformations that the new catalytic compositions or metal complexes enhance, and it is an object of this invention to provide catalysts and methods for such transformations. The compositions and metal complexes are useful as catalysts for various chemical transformations, particularly cross coupling reactions. Specifically, the preparation of polycyclic aromatic compounds by a cross-coupling reaction of a first aromatic compound and second aromatic compound, more specifically with aromatic boron compounds and aromatic halogen compounds or perfluoroalkylsulfonates may be performed, and it is an object of this invention to provide catalysts and methods for such cross coupling reactions. The benefit of using these catalysts in such reactions is generally higher conversions (e.g., turnovers) when using less costly starting materials.
Further aspects of this invention will be evident to those of skill in the art upon review of this specification.
DETAILED DESCRIPTION OF THE INVENTION
As used herein, the phrase “characterized by the formula” is not intended to be limiting and is used in the same way that “comprising” is commonly used. The term “independently selected” is used herein to indicate that the R groups, e.g., R
1
, R
2
, R
3
or R
4
can be identical or different (e.g. R
1
, R
2
and R
3
may all be substituted alkyls or R
1
and R
2
may be a substituted alkyl and R
3
may be an aryl, etc.). A named R group will generally have the structure that is recognized in the art as corresponding to R groups having that name. For the purposes of illustration, representative R
Bei Xiaohong
Guram Anil
Nazario-Gonzalez Porfirio
Symyx Technologies Inc.
LandOfFree
Methods for using phosphine ligands in compositions for... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Methods for using phosphine ligands in compositions for..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Methods for using phosphine ligands in compositions for... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2544996