Metal catalyzed reactions

Details Metal catalyzed reactions Metal catalyzed reactions

2002-03-29

2004-02-03

Wu, David W. (Department: 1713)

Synthetic resins or natural rubbers -- part of the class 520 ser

Synthetic resins

Polymers from only ethylenic monomers or processes of...

C526S134000, C526S110000, C526S115000, C526S117000, C568S006000

Reexamination Certificate

active

06686428

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates to a composition and process of forming chemical bonds, such as carbon-carbon and carbon-heteroatom bonds. The present invention has particular applicability to the formation of chemical bonds by transmetallation reaction chemistry.
BACKGROUND
Over the past several decades, palladium (Pd) catalyzed carbon-carbon bond formation reactions have been extensively studied and widely applied in organic synthesis [Tsuji, J.
Transition Metal Reagents and Catalysis,
John Wiley: Chichester, 2000]. The ultimately formed chemical bonds are produced by a sequence of intermediates. These include the formation of an aryl or alkenylpalladium halide complex generated by oxidative addition of the aryl or alkenylhalide with Pd. These complexes can, in turn, undergo transmetallation with many reagents. This reaction sequence is followed by reductive elimination to form a carbon-carbon bond and to regenerate a Pd (0) species. This system provide a methods for developing many crosscoupling reactions. The following authors are known to employ the element in the parentheticals for coupling reactions: Suzuki (boron, B), Stille (tin, Sn), Negeshi (zinc and aluminum, Zn and Al), Kumada (magnesium, Mg) [Miyaura, N.; Suzuki. A.
Chem. Rev.
1995, 95, 2457; Knight, D. W. In
Comprehensive Organic Synthesis;
Trost, B. M.; Fleming, I., Ed.; Pergamon Press: Oxford, 1991, Vol 3, Chapter 2.3; Suzuki, A.
Pure Appl. Chem.
1985, 57, 1749; Tamao, K.; Kumada, M. in
The Chemistry of the Metal
-
Carbon Bond
(Ed., F. R. Hartley), Vol. 4, Wiley, N.Y., 1987, Chapter 9 p 819; Suzuki, A.
Pure Appl. Chem.
1985, 57, 1749; Stille, J. K. Angew Chem. Int. Ed. Engl. 1986, 25, 508; Negishi, E.
Acc. Chem. Res.
1982, 15, 340. (i) Kumada, M.
Pure Appl. Chem.
1980, 52, 669].
In contrast, palladium-catalyzed homocoupling reactions have not been studied extensively, although some homocoupling reactions of aryl and alkenyl halides facilitated by a Pd species are known. [See, e.g., Hennings, D. D.; Iwama, T.; Rawal, V. H.
Org. Lett.
1999, 1, 1205; Hassan, J.; Penalva, V.; Lavenot, L.; Gozzi, C.; Lemaire, M.
Tetrahedron
1998, 54, 13793; Jutand, A.; Mosleh, A.
J. Org. Chem.
1997, 62, 261; Smith, K. A.; Campi, E. M.; Jackson, W. R.; Marcuccio, S.; Naeslund, C. G. M.; Deacon, G. B.
Synlett,
1997, 131; Jutand, A.; Mosleh, A.
Synlett,
1993, 568; Jutand, A.; Negri, S.; Mosleh, A.
Chem. Commun.,
1992, 1792; Miura, M.; Hashimnoto, H.; Itoh, K.; Nomura, M.
Chem. Lett.
1990, 459]. Other known coupling reactions include Glazer coupling (Chem Ber 1869, 2, 422, Cadiot P, Chodkiewwicz, W. Chemistry of Acetylenes, 1969, Marcel Dekker, New York, p 597), Ullman-type Coupling reactions (Semmelhack, M. F.; Helwuist, P. M.; Jones, L. D. J. Am. Chem. Soc. 1971, 93 5908; Kende, A.; Liebeskind, L. S. Braitsch, D. M. Tetrahdedron Lett. 1975, 3375; Prerce, V.; Bae, J. Y.; Zhao, M.; Hill, D. H. J. Org. Chem. 1994, 60, 176). For forming carbon-heteroatom bonds, Hartwig and Buchwald have made a couple of catalysts. Hartwig, J. F. Angew Chem. Int. Ed. Engl. 1998, 37, 2047; Wolfe, J. P.; Wagaw, S.; Buchwald, S. L. J. Am. Chem. Soc. 1996, 118, 1133; Mann, G.; Hartwig, J. F. J. Org. Chem. 1997, 62, 5413).
The following table summarizes coupling reactions.
Although the above mentioned metal-catalyzed and metal-facilitated carbon-carbon and carbon-heteroatom bond formation reactions are useful for organic synthesis, they are also limited. For example, an Ullman coupling reaction generally is carried out under harsh conditions and many hindered or aryl halides having one or more electron donating groups resist coupling. Glaser coupling requires the presence of oxygen, which can destroy many sensitive products, particularly diynes. A number of alkynes with functional groups do not undergo coupling in a Glaser coupling reaction. Moreover, the coupling reaction is generally not applicable to polymerization or oligomerization reactions.
The synthesis of diynes is particularly problematic as diynes are not stable and prone to decomposition. Therefore, only alkyl halides, aryl halides (e.g., RI or RBr) that react under mild conditions will couple. In Sonogashira, Suzuki, Stille, Negishi, Kumada, Hartwig-Buchwald coupling reactions, oxidative addition of aryl halides can be a difficult step. This is particularly true if the aryl halide has two groups substituted in adjacent positions. To minimize or avoid the oxidative addition of these difficult substrates would be of great interest in organic synthesis. For a Suzuki coupling reaction, a known side reaction product is dehalogenation reaction. In Sonogashira, Suzuki, Stille, Negishi, Kumada, Hartwig-Buchwald coupling reactions, the oxidative addition of RX when R is a simple alkyl group with a &bgr;-hydrogen is a slow process and metal compounds can easily form undesirable &bgr;-hydrogen elimination products. This has been a major limitation of these coupling reactions.
Hence, there is a need for metal-catalyzed catalytic reactions which can improve coupling reactions, or, ideally, overcome many of the limitation of prior art processes. There is also a need in the chemical industry for making existing pharmaceutical products, agrochemical products, polymers products and as well as new products by a facile chemical bond forming reaction.
SUMMARY OF THE INVENTION
An advantage of the present invention is a composition for chemical bond formation.
An additional advantage of the present invention is a method of forming chemical bonds by transmetallation.
Additional advantages, and other features of the present invention will be set forth in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from the practice of the present disclosure. The advantages may be realized and obtained as particularly pointed out in the appended claims.
According to the present invention, the foregoing and other advantages are achieved in part by a composition comprising at least one &agr;-halo carbonyl compound; and one or more transmetallation reagents.
Embodiments include, compositions having a base, e.g. a compound having an available pair of electrons. The forgoing bases include triethyl amine (Et
3
N), DABCO, Et
2
NH, NaOR
b
, Na
2
CO
3
, KF, K
3
PO
4
, NaOAc, KOH, and R
b
NX, where R
b
is one or more of an H, alkyl groups and X is an anion, such as a halogen or ester. The composition includes at least one transmetallation reagent. This reagent can be prepare prior to forming the composition or in situ.
Transmetallation reagents are formed by the addition of a metal or metal catalyst to a target compound. The target compound is the compound undergoing chemical bond formation. For example, transmetallation reagents include metal complexes, such as RM, RB(OH)
2
, RBR′
2
, RSnR′
3
, RZnX, RHgX, RMgR, RSiR′
3
, RCu, ROM, RNHM, RAlR′2, wherein R and R′ are independently an aryl or alkyl group and M is a metal. Other organometallic species are also contemplated. Additionally, an &agr;-halo carbonyl species which can easily undergo oxidative addition with redox active metals is included in this composition for coupling reactions.
Another aspect of the present invention is forming chemical bonds. Bond formation can advantageously be carried out in both intermolecular reactions (i.e. between two or more target compounds), or intramolecular (within the same target compound) reactions. Chemical bond formation methods can be used to make biologically active compounds or polymers, such as SP-carbon type of molecules. The method comprises combining at least one transmetallation reagent comprising a target compound with at least one &agr;-halo carbonyl compound; and forming a bond to or within the target compound of the transmetallation reagent.
In another aspect of the invention, a process for hydroboration and asymmetric hydroboration of boric compounds and coupling of bisboronic compounds by either intramolecular or inter

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