Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Reexamination Certificate
2000-01-18
2002-04-09
Raymond, Richard L. (Department: 1624)
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
C560S231000, C568S425000, C568S440000, C568S445000, C568S446000
Reexamination Certificate
active
06369243
ABSTRACT:
TECHNICAL FIELD
The present invention relates to organic reagents and their use as catalysts for a variety of reactions. More particularly, this invention relates to the use of a heteroatom-containing activator and an acid as a catalyst composition for various bond-forming reactions. Even more particularly, this invention relates to the preparation of chiral products from either chiral or achiral starting materials using a heteroatom-containing activator and an acid as a catalytic composition of matter. The invention finds utility in the fields of organic synthesis, catalysis and chiral chemistry.
BACKGROUND
Ancillary (or “spectator”) ligand-metal coordination complexes (e.g., organometallic complexes) and compositions are useful as catalysts, stoichiometric reagents and therapeutic agents. The ancillary ligand contains functional groups that bind to one or more metal centers and remain associated therewith, providing an opportunity to modify the steric, electronic and chemical properties of the active sites of the complex, i.e., the metal centers.
Unfortunately, many organometallic reagents are expensive and depending on their catalytic activity may be not be commercially viable. Moreover, many organometallic complexes are useful only for very specific chemical reactions and do not have broad utility as catalysts for a variety of different types of reactions. This problem may be emphasized for the catalysis of reactions leading to chiral molecules, particularly the conversion of either chiral or achiral molecules via enantioselective catalysis to provide a chiral product.
Over the last 30 years enantioselective catalysis has become one of the most important frontiers in exploratory organic synthetic research. In the pharmaceutical industry and other industries, the use of pure enantiomeric molecules is often important for safety and efficacy. Thus, in the production of pharmaceuticals, use of catalysts or reagents that preferentially produce one enantiomer of a molecule relative to another enantiomer is particularly advantageous. Unfortunately, the catalysts that produce such enantiomers are typically organometallic complexes that are specific for a particular reaction. In addition, there is no way to predict with any reasonable accuracy which enantiomer will result. Examples of organometallic catalysts used to prepare chiral materials include BINOL-based complexes (Mikami et al. (1994)
J. Am. Chem. Soc
. 116:2812; Kobayashi et al. (1994)
J Am. Chem. Soc
. 116:4083; Mikami et al. (1989)
J. Am. Chem. Soc
. 111:1940; Mikami et al. (1994)
J. Am. Chem. Soc
. 116:4077; Keck et al. (1993)
J. Am. Chem. Soc
. 115:8467; Keck et al. (1995)
J Am. Chem. Soc
. 117:2363), BINAP-based complexes (Miyashita et al. (1980)
J. Am. Chem. Soc
. 102:7932; Miyashita et al. (1984)
Tetrahedron
40:1245; Takaya et al. (1986)
J Org. Chem
. 51:629; Takaya et al. (1988)
Org. Synth
. 67:20; Cai et al. (1995)
Tetrahedron Lett
. 36:7991), DUPHOS complexes (Burk et al. (1990)
Organometallics
9:2653; Burk et al. (1993)
J. Am. Chem. Soc
. 115:10125; Burk et al. (1992)
J. Am. Chem. Soc
. 114:6266; Burk et al. (1995)
J. Am. Chem. Soc
. 117:9375); salen-based complexes (i.e., organometallic complexes containing the N,N′-bis(3,5-di-t-butylsalicylidene)-1,2-cyclohexanediamino ligand; see, e.g., Li et al. (1993)
J. Am. Chem. Soc
. 115:5326, and Evans et al. (1993)
Tetrahedron Lett
. 34:7027), and bisoxazoline-containing compounds (Evans et al. (1993)
J. Am. Chem. Soc
. 115:6460; Evans et al. (1997)
J. Am. Chem. Soc
. 119:7893; Evans et al. (1996)
Tetrahedron Lett
. 37:7481; Corey et al. (1992)
Tetrahedron Lett
. 33:6807; Gothelf et al. (1996)
J. Org. Chem
. 61:346).
Despite the observed need and relatively few, narrow solutions, relatively few asymmetric transformations have been reported which employ organic molecules as reaction catalysts. There is tremendous potential for academic, economic and environmental benefit should versatile, chiral organic catalysts be developed. Only a few researchers have disclosed organic catalysts useful for preparing chiral materials. See, e.g.,
Asymmetric Catalysis in Organic Synthesis
, Noyori, R., Ed. (New York: Wiley, 1994) and
Asymmetric Synthesis
, Ojima, I., Ed. (New York: VCH, 1993), and references cited therein. Also see Yang et al. (1998)
J. Am. Chem. Soc
. 120(24):5943-5952, who disclose the use of a dioxirane to catalyze enantioselective epoxidation, Shi et al. (1995)
J. Chem. Research
(S):46-47(
J. Chem. Research (M):
0401-0411), who disclose preparation of chiral quaternary ammonium salts stated to be useful as chiral phase-transfer catalysts by reaction of (R)-(+)-2,2′-bis(bromomethyl)-6,6′-dinitrobiphenyl and (R)-(+)-2,2′-bis(bromomethyl)-1,1′-binaphthyl with cyclic amines such as pyrrolidine, piperidine and 4-hydroxypiperidine. International Patent Publication No. WO 92/02505 to Castelijns also discloses use of a secondary amine in a catalytic transformation, i.e., in conversion of an unsaturated imine to a pyridine product, by reaction with an aldehyde or ketone.
The aforementioned organic catalysts are not, however, useful in catalyzing a broad range of chemical transformations, but are specific for a particular reaction and thus have limited utility. There is accordingly a need in the art for organic catalysts that are versatile with respect to the types of reactions that can be catalyzed, are inexpensive to synthesize, and are readily capable of scale-up for commercialization. It is also desirable that such catalysts be capable of preparing chiral products from starting materials that may be either chiral or achiral in nature.
SUMMARY OF THE INVENTION
Accordingly, it is a primary object of the invention to address the aforementioned need in the art and provide methods, catalyst compositions and reaction systems for chemically transforming a substrate, wherein the catalyst composition is composed of nonmetallic components, is useful for catalyzing a wide variety of reactions and reaction types, is relatively inexpensive to synthesize, and is simple and straightforward to work with and scale up. Importantly, the catalyst composition may also contain a chiral component that enables enantioselective catalysis and synthesis of a chiral product.
It is another object of the invention to provide a process for catalytically transforming a compound containing a functional group to provide a product in which the functional group contains at least one newly formed covalent bond.
It is another object of the invention to provide such a process wherein the reaction is carried out in the presence of a catalyst composition composed of a heteroatom-containing activator and an acid.
It is still another object of the invention to provide such a process wherein the reaction is carried out in the presence of a catalyst composition composed of a salt of a heteroatom-containing activator and an acid.
It is yet another object of the invention to provide a chemical reaction wherein an nonmetallic, organic catalyst composition lowers the LUMO (lowest unoccupied molecular orbital) of a substrate to facilitate reaction thereof.
It is a further object of the invention to provide such processes and reactions wherein the catalyst composition contains a chiral component.
It is still a further object of the invention to provide novel compounds in the form of a positively charged &agr;,&bgr;-unsaturated imine.
It is an additional object of the invention to provide a catalyst composition composed of a heteroatom-containing activator and an acid.
It is still an additional object of the invention to provide a reaction system composed of the aforementioned catalyst composition and a substrate such as an &agr;,&bgr;-unsaturated carbonyl compound.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention.
Generally, the inventi
Ahrendt Kateri A.
MacMillan David W. C.
Raymond Richard L.
Reed Dianne E.
Reed & Associates
The Regents of the Univerisity of California
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