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  • C07F17/00—Metallocenes
  • C07F17/02—Metallocenes of metals of Groups 8, 9 or 10 of the Periodic Table
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  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
  • B01J31/16—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes
  • B01J31/18—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes containing nitrogen, phosphorus, arsenic or antimony as complexing atoms, e.g. in pyridine ligands, or in resonance therewith, e.g. in isocyanide ligands C=N-R or as complexed central atoms
  • B01J31/1845—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes containing nitrogen, phosphorus, arsenic or antimony as complexing atoms, e.g. in pyridine ligands, or in resonance therewith, e.g. in isocyanide ligands C=N-R or as complexed central atoms the ligands containing phosphorus
  • B01J31/1865—Phosphonites (RP(OR)2), their isomeric phosphinates (R2(RO)P=O) and RO-substitution derivatives thereof
  • B01J31/187—Amide derivatives thereof
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
  • B01J31/16—Catalysts comprising hydrides, coordination complexes or organic compounds containing coordination complexes
  • B01J31/22—Organic complexes
  • B01J31/2282—Unsaturated compounds used as ligands
  • B01J31/2295—Cyclic compounds, e.g. cyclopentadienyls
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  • C07C51/347—Preparation of carboxylic acids or their salts, halides or anhydrides by reactions not involving formation of carboxyl groups
  • C07C51/36—Preparation of carboxylic acids or their salts, halides or anhydrides by reactions not involving formation of carboxyl groups by hydrogenation of carbon-to-carbon unsaturated bonds
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  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C67/00—Preparation of carboxylic acid esters
  • C07C67/30—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group
  • C07C67/303—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group by hydrogenation of unsaturated carbon-to-carbon bonds
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  • C07F17/00—Metallocenes
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  • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
  • C07F9/00—Compounds containing elements of Groups 5 or 15 of the Periodic Table
  • C07F9/02—Phosphorus compounds
  • C07F9/06—Phosphorus compounds without P—C bonds
  • C07F9/22—Amides of acids of phosphorus
  • C07F9/24—Esteramides
  • C07F9/2454—Esteramides the amide moiety containing a substituent or a structure which is considered as characteristic
  • C07F9/2458—Esteramides the amide moiety containing a substituent or a structure which is considered as characteristic of aliphatic amines
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  • C07F9/00—Compounds containing elements of Groups 5 or 15 of the Periodic Table
  • C07F9/02—Phosphorus compounds
  • C07F9/547—Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom
  • C07F9/6564—Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom having phosphorus atoms, with or without nitrogen, oxygen, sulfur, selenium or tellurium atoms, as ring hetero atoms
  • C07F9/6571—Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom having phosphorus atoms, with or without nitrogen, oxygen, sulfur, selenium or tellurium atoms, as ring hetero atoms having phosphorus and oxygen atoms as the only ring hetero atoms
  • C07F9/657154—Cyclic esteramides of oxyacids of phosphorus
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2231/00—Catalytic reactions performed with catalysts classified in B01J31/00
  • B01J2231/60—Reduction reactions, e.g. hydrogenation
  • B01J2231/64—Reductions in general of organic substrates, e.g. hydride reductions or hydrogenations
  • B01J2231/641—Hydrogenation of organic substrates, i.e. H2 or H-transfer hydrogenations, e.g. Fischer-Tropsch processes
  • B01J2231/645—Hydrogenation of organic substrates, i.e. H2 or H-transfer hydrogenations, e.g. Fischer-Tropsch processes of C=C or C-C triple bonds
• • B—PERFORMING OPERATIONS; TRANSPORTING
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  • B01J2531/00—Additional information regarding catalytic systems classified in B01J31/00
  • B01J2531/80—Complexes comprising metals of Group VIII as the central metal
  • B01J2531/82—Metals of the platinum group
  • B01J2531/822—Rhodium
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  • C07B—GENERAL METHODS OF ORGANIC CHEMISTRY; APPARATUS THEREFOR
  • C07B2200/00—Indexing scheme relating to specific properties of organic compounds
  • C07B2200/07—Optical isomers

Definitions

• This invention pertains to certain novel phosphorus-containing ligands useful in the formation of catalysts useful in carrying out a wide variety of reactions. More specifically, this invention pertains to a class of novel phosphine-phosphoramidite compounds which may be employed in combination with a catalytically-active metal to effect a wide variety of reactions such as asymmetric hydrogenations, asymmetric reductions, asymmetric hydroborations, asymmetric olefin isomerizations, asymmetric hydrosilations, asymmetric allylations, asymmetric conjugate additions, and asymmetric organometallic additions.
• Asymmetric catalysis is the most efficient method for the generation of products with high enantiomeric purity, as the asymmetry of the catalyst is multiplied many times over in the generation of the chiral product. These chiral products have found numerous applications as building blocks for single enantiomer pharmaceuticals as well as in some agrochemicals.
• the asymmetric catalysts employed may be enzymatic or synthetic in nature. The latter types of catalyst have much greater promise than the former due to much greater latitude of applicable reaction types.
• Synthetic asymmetric catalysts are usually composed of a metal reaction center surrounded by one or more organic ligands. The ligands usually are generated in high enantiomeric purity, and are the agents inducing the asymmetry.
• ligands are, in general, difficult to make and therefore expensive.
• a notable exception are the chiral phosphine-aminophosphine ligands based on a phosphine-amine backbone described by Boaz et al., US Patent 6590115. These phosphine-aminophosphine compounds are useful as metal complexes for asymmetric catalysis and are readily prepared and air-stable.
• Monodentate phosphoramidite ligands useful for asymmetric catalysis have been reported by de Vries, et al., Angew. Chem. Int. Ed. Engl. 1996, 35, 2374-2376; Malda, et al., Org. Lett. 2001, 3, 1169-1171 ; Alexakis, et al., J. Am. Chem. Soc. 2002, 124, 5262-5263; Pena, et al., J. Am. Chem. Soc. 2002, 124, 14552-14553; Ohmura, et al., J. Am. Chem. Soc. 2002, 124, 15164-15165; Urbaneja, et al., Tetrahedron Lett.
• the monodentate ligands have a single ligating group and have demonstrated moderate to high enantioselecitivity for a variety of asymmetric catalytic reactions including asymmetric hydrogenations.
• the monodentate ligands are, in general, prepared by reacting a diol with phosphorus trichloride followed by reaction with an amine (de Vries, et al., Angew. Chem. Int. Ed. Engl. 1996, 35, 2374-2376).
• novel phosphine-phosphoramidite compounds which may be employed in combination with a catalytically- active metal to effect a wide variety of reactions such as asymmetric hydrogenations, asymmetric reductions, asymmetric hydroborations, asymmetric olefin isomerizations, asymmetric hydrosilations, asymmetric allylations, asymmetric conjugate additions, and asymmetric organometallic additions.
• the novel compounds of the present invention have the formula :
• R and R 3 are substituted or unsubstituted, branched- or straight- chain C-1-C-2 0 alkyl, substituted or unsubstituted C 3 -Cs cycloalkyl, substituted or unsubstituted C 6 -C 20 carbocyclic aryl, or substituted or unsubstituted C 4 - C 2O heteroaryl having one to three heteroatoms wherein the heteroatoms are selected from sulfur, nitrogen, and oxygen;
• R 1 and R 2 are, independently, achiral or substantially enantiomerically pure (i.e., an enantiomeric excess of 90% or greater) substituted or unsubstituted, branched- or straight-chain C 1 -C 20 alkyl, substituted or unsubstituted C 3 -C 8 cycloalkyl, substituted or unsubstituted C 6 -C 2 O carbocyclic aryl, substituted or unsubstituted C 4 -C 2 0 heteroaryl having one to three heteroatoms wherein the heteroatoms are selected from sulfur, nitrogen, and oxygen, or R 1 and R 2 collectively represent a substituted or unsubstituted achiral, chiral and racemic, or substantially enantiomerically pure divalent alkylene, cycloalkylene or arylene radical wherein the chain of carbon atoms in the main chain that joins the amidite oxygen atoms in formula 1 contains 2 to 8 carbon atoms;
• L is a divalent chiral radical selected from substituted or unsubstituted, branched- or straight-chain C1-C20 alkylene, substituted or unsubstituted C 3 -Cs cycloalkylene, substituted or unsubstituted C 6 -C 20 carbocyclic arylene, substituted or unsubstituted C 4 -C 2O heteroarylene having one to three heteroatoms wherein the heteroatoms are selected from sulfur, nitrogen, and oxygen, or substituted or unsubstituted metallocenylmethylene, wherein L is substantially enantiomerically pure.
• a second embodiment of our invention is a process for the preparation of phosphine-phosphoramidite compounds of formula 1 which comprises the steps of:
• R, R 1 , R 2 and R 3 are defined above;
• X is halogen, preferably bromo or, especially, chloro.
• a third embodiment of the present invention pertains to metal complex compounds comprising a phosphine-phosphoramidite compound of formula 1 and a catalytically-active metal selected from Group VIII metals.
• a fourth embodiment of the present invention pertains to a process for the hydrogenation of a hydrogenatable compound which comprises contacting the hydrogenatable compound with hydrogen in the presence of a catalyst complex of a phosphine-phosphoramidite compound of formula 1 and a catalytically-active metal.
• the alkyl groups that may represent each of R, R 1 , R 2 and R 3 may be straight- or branched-chain aliphatic hydrocarbon radicals containing from one up to 20 carbon atoms and may be substituted, for example, with one to three groups selected from Ci-C ⁇ -alkoxy, cyano, C 2 -C 6 - alkoxycarbonyl, C 2 -C 6 -alkanoyloxy, aryl and halogen.
• Ci-C ⁇ -alkoxy cyano
• C 2 -C 6 - alkoxycarbonyl C 2 -C 6 -alkanoyloxy
• aryl and halogen aryl and halogen.
• C 3 - Cs-cycloalkyl is used to denote a saturated, carbocyclic hydrocarbon radical having three to eight carbon atoms.
• the aryl groups that each of R, R 1 , R 2 and R 3 may represent include phenyl, naphthyl, anthracenyl or phenyl, naphthyl, or anthracenyl substituted with one to three substituents selected from Ci-C 6 -alkyl, substituted CrC 6 -alkyl, C 6 -Ci O aryl, substituted C 6 -Ci 0 aryl, Ci-C 6 -alkoxy, halogen, cyano, Ci-C 6 -alkanoyloxy, Ci-C 6 -alkylthio, Ci-C 6 -alkylsulfonyl, trifluoromethyl, C 2 -C 6 -alkoxycarbonyl, C 2 -C 6 -alkanoylamino and -O-R 8 , S-R 8 -SO 2 -R 8 , -NHSO 2 R 8 and -NHCO 2 R 8 , wherein R 8
• the C 4 -C 20 heteroaryl radicals described herein include a 5- or 6- membered aromatic ring containing one to three heteroatoms selected from oxygen, sulfur and nitrogen.
• heteroaryl groups are thienyl, furyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, isothiazolyl, oxazolyl, isoxazolyl, triazolyl, thiadiazolyl, oxadiazolyl, tetrazolyl, pyridyl, pyrimidyl, benzoxazolyl, benzothiazolyl, benzimidazolyl, indolyl and the like.
• the heteroaryl radicals may be substituted, for example, with up to three groups such as Ci-C 6 -alkyl, Ci-C 6 -alkoxy, substituted Ci-C 6 -alkyl, halogen, CrC 6 - alkylthio, aryl, arylthio, aryloxy, C 2 -C 6 -alkoxycarbonyl and C- 2 -C6- alkanoylamino.
• the heteroaryl radicals also may be substituted with a fused ring system, e.g., a benzo or naphtho residue, which may be unsubstituted or substituted, for example, with up to three of the groups set forth in the preceding sentence.
• halogen is used to include fluorine, chlorine, bromine, and iodine.
• R 1 and R 2 collectively may represent a divalent alkylene, cycloalkylene or arylene radical wherein the chain of carbon atoms, e.g., an alkylene or alkenylene group, in the main chain that joins the amidite oxygen atoms in formula 1 contains 2 to 8 carbon atoms. More specifically, a divalent radical collectively represented by R 1 and R 2 may contain a total of 2 to 20 carbon atoms and may be substituted or unsubstituted and connects the two amidite oxgen atoms by a chain of 2 to 8 carbons. The divalent radical collectively represented by R 1 and R 2 may be substituted with the substituents described in the preceding paragraph.
• divalent radicals examples include 1 ,2-ethanediyl (ethylene), 1 ,3-propanediyl (trimethylene), 1 ,4-butanediyl (tetramethylene), 2,3-butanediyl, 2,2'-biphenyldiyl, 1 ,1'-binaphthyl-2,2'-diyl and the like wherein the divalent radical may be achiral, chiral and racemic, or chiral and substantially enantiomerically pure.
• each of the references herein to groups or moieties having a stated range of carbon atoms includes not only the Ci group (methyl) and C 6 group (hexyl) end points, but also each of the corresponding individual C 2 , C 3 , C 4 and C 5 groups.
• each of the individual points within a stated range of carbon atoms may be further combined to describe subranges that are inherently within the stated overall range.
• the term "Ci-C 6 -aIkyI” includes not only the individual moieties Ci through C 6 , but also contemplates subranges such as "C 2 -C 5 -alkyl.”
• a preferred class of the novel compounds provided by the present invention have formulas 2 or 3 (the enantiomer of 2)
• R, R 1 , R 2 and R 3 are as defined above;
• R 4 , R 5 , and R 6 are, independently, hydrogen, substituted or unsubstituted, branched- or straight-chain C 1 -C2 0 alkyl, substituted or unsubstituted C3-C- 8 cycloalkyl, substituted or unsubstituted C 6 -C 2 O carbocyclic aryl, or substituted or unsubstituted C 4 -C 2O heteroaryl having one to three heteroatoms wherein the heteroatoms are selected from sulfur, nitrogen, and oxygen; n is O to 3; m is 0 to 5; and
• M is a metal selected from Groups IVB, VB, VIB, VIIB or VIII.
• R 4 , R 5 , and R 6 are set forth above in the description of the radicals that R, R 1 , R 2 and R 3 may represent.
• the metals represented by M include iron, ruthenium, and osmium.
• a more preferred group of the novel phosphine-phosphoramidite compounds have formulas 2 or 3 (the enantiomer of 2)
• R is aryl, most preferably phenyl
• R 1 is aryl, most preferably phenyl, 4-methoxyphenyl, or 4-trifluoromethylphenyl
• R 2 is aryl, most preferably phenyl, 4-methoxyphenyl, or 4-trifluoromethylphenyl, or R 1 and R 2 are collectively 1 ,2-ethanediyI, 1,3-propanediyl, 1,2-benzenediyl, 2,2'-biphenyldiyl, racemic 1,1'-binaphthyl-2,2'-diyl, (R 1 R)- 1 ,1'-binaphthyl- 2,2'-diyl, or (S 1 S)- 1 ,1'-binaphthyl-2,2'-diyl;
• R 3 is hydrogen, Ci-C 6 alkyl, or aryl, most preferably methyl
• R 4 is hydrogen or Ci-
• a further embodiment of our invention is a process for preparing phosphine-phosphoramidite compounds having formula 1
• R, R 1 , R 2 and R 3 are as defined above; and X is a halogen, preferably bromo or, especially, chloro.
• steps (1 ) and (2) may optionally be carried out in the presence of an acid acceptor.
• the process may be carried out in an inert, organic solvent such as a cyclic or acyclic ether, e.g., diethyl ether, diisopropyl ether, tert-butyl methyl ether, or tetrahydrofuran; aromatic hydrocarbons, e.g., benzene, toluene, or xylene; aliphatic and alicyclic hydrocarbons, e.g., hexane, heptane, or cyclohexane; or mixtures of any 2 or more of the foregoing.
• organic solvent such as a cyclic or acyclic ether, e.g., diethyl ether, diisopropyl ether, tert-butyl methyl ether, or tetrahydrofuran; aromatic hydrocarbons, e.g., benzene, toluene, or xylene; aliphatic and alicycl
• Step (1) of the process may be carried out at a temperature between -100 0 C and the boiling point of the solvent, preferably -80° to 40 0 C.
• Step (1) may optionally be carried out in the presence of an acid acceptor, preferably a C 3 -C 15 tertiary amine or a pyridine, with the preferred amine being triethylamine.
• the relative amounts of reactant 4 and phosphorus trihalide PX 3 employed in step (1) typically provides a reactant 4 to phosphorus trihalide PX 3 mole ratio of 0.5:1 to 4:1 , preferably 1:1 to 1.5:1.
• the amount of acid acceptor is at least 1.0 moles per mole of reactant 4, and is typically 1.0 to 2.0 moles of acid acceptor per mole of reactant 4.
• results obtained from subsequent reactions indicate that the intended dihaloaminophosphine 5 produced in this reaction (i.e., when L is a metallocenylmethylene) is substantially uncontaminated with monohalodiaminophosphine and triaminophosphine. This is surprising, as a statistical mixture of these species might be expected. Although not wishing to be bound by theory, these results may be due to the steric congestion engendered by the amine used which limits the number of amines that can react with the phosphorus trihalide. Although not necessary , dihalide intermediate 5 may be isolated before conducting the second step of the process.
• Step (2) of the process may be carried out at a temperature between -100 0 C and the boiling point of the solvent, and preferably at -80° to 40°C.
• This step may also be carried out in the optional presence of an acid acceptor, preferably a C 3 -C 15 tertiary amine or a pyridine, with the preferred amine being triethylamine.
• the amount of acid acceptor is typically 2.0 to 5.0 moles of acid acceptor per mole of intermediate 5.
• the amount of hydroxyl reactant(s) employed normally should provide at least 2 equivalents of hydroxyl and up to 10 equivalents of hydroxyl per mole of dihalide intermediate 5.
• the preferred amount is 2 equivalents of hydroxyl reactant(s) per mole of dihalide 5.
• the hydroxyl reactants 6 and 7 preferably are the same, and preferably are phenol, 4-methoxyphenol, or 4- trifluoromethylphenol.
• the diol reactant 8 preferably is ethylene glycol, 1 ,3- propylene glycol, 1 ,2-benzenediol, 2,2'-biphenol, racemic 1 ,1 '-bi-2-naphthol, (S)-1 , 1 '-bi-2-naphthol, or (R)-1 , 1 '-bi-2-naphthol.
• Product 1 may be isolated from the reaction mixture according to procedures well-known to those skilled in the art. Examples of such procedures include extraction, filtration and crystallization. Product 1 may be purified if necessary using conventional methods, e.g., extraction, chromatography and crystallization processes.
• the present invention also relates to complexes of the phosphine- phosphoramidite compounds of formula 1 with a catalytically-active metal.
• Such complexes are effective catalysts for promoting a large number of possible reactions employing a wide variety of reactants. Examples of possible reactions include asymmetric hydrogenations, asymmetric reductions, asymmetric hydroborations, asymmetric olefin isomerizations, asymmetric hydrosilations, asymmetric aliylations, asymmetric conjugate additions and asymmetric organometallic additions.
• the particular metal selected for complexation with the phosphine- phosphoramidite compounds of formula 1 depends on the desired reaction.
• the metal may be selected from Group VIII metals, with rhodium, ruthenium, and iridium being preferred.
• the complexes may be prepared and isolated prior to use, it is preferable to prepare a solution of the complex in situ from phosphine-phosphoramidite compound 1 and a metal pre-catalyst in a solvent, and use this solution directly in subsequent reactions.
• the relative amounts of phosphine-phosphoramidite compound 1 and catalytically-active metal employed typically provide a phosphorus:metal atomic ratio of 1:1 to 5:1 , preferably 2:1 to 3:1.
• the complexes of the present invention are generally prepared by mixing the metal precatalyst and phosphine-phosphoramidite compound 1 in an inert solvent chosen from aliphatic hydrocarbons, e.g., hexane, heptane, octane and the like; aromatic hydrocarbons, e.g., toluene, xylenes and the like; cyclic and acyclic ethers, e.g., tert-butyl methyl ether, diisopropyl ether, tetrahydrofuran (THF) and the like; lower alkanols, e.g., methanol, ethanol, n-propanol, isopropanol, n-butanol and the like; halogenated aliphatic or aromatic hydrocarbons, e.g., dichloromethane, tetrachloroethylene, chloroform, chlorobenzene and the like; dial
• the present invention includes a process for the hydrogenation of a hydrogenatable compound, which comprises contacting the hydrogenatable compound with hydrogen in the presence of a catalyst complex of a phosphine-phosphoramidite compound of formula 1 and a catalytically-active metal under hydrogenation conditions of temperature and pressure.
• the catalytically-active metal complexed with the compound of formula 1 preferably is rhodium, iridium, or ruthenium, and most preferably is rhodium.
• the amount of complex utilized in the hydrogenation process may vary between 0.00005 and 0.5 molar equivalents based on the hydrogenatable starting material, with more complex usually providing faster reaction rates.
• the reaction atmosphere is hydrogen, but may also contain other materials that are inert to the reaction conditions.
• the reaction can be run at atmospheric pressure or at elevated pressure, e.g., from 0.5 to 200 bars gauge (barg).
• the reaction is run at a temperature which affords a reasonable rate of conversion, which can be as low as -50 0 C but is usually between ambient temperature and the boiling point (or apparent boiling point at elevated pressure) of the lowest boiling component of the reaction mixture.
• Our novel hydrogenation process normally is operated in the presence of an inert organic solvent such as aliphatic hydrocarbons, e.g., hexane, heptane, octane and the like; aromatic hydrocarbons, e.g., toluene, xylenes and the like; cyclic and acyclic ethers, e.g., tert-butyl methyl ether, diisopropyl ether, tetrahydrofuran (THF) and the like; lower alkanols, e.g., methanol, ethanol, n-propanol, isopropanol, n-butanol and the like; halogenated aliphatic or aromatic hydrocarbons, e.g., dichloromethane, tetrachloroethylene, chloroform, chlorobenzene and the like; dialkyl ketones, e.g., acetone, 2-butanone, 3-p
• a hydrogenation that is of particular interest to the pharmaceutical industry that may be performed using the inventive complexes is an asymmetric hydrogenation of a dehydroamino acid derivative ("enamide") to produce the corresponding amino acid derivative.
• Catalyst complexes of the phosphine-phosphoramidite compounds of formula 1 and a catalytically- active metal exhibit particularly high enantioselectivity for the asymmetric hydrogenation of enamides to produce the corresponding amino acid derivatives.
• our novel hydrogenation process involves, for example, the preparation of a compound having formula 9
• R 9 , R 10 , and R 12 are independently, hydrogen, substituted or unsubstituted, branched- or straight-chain Ci to C 20 alkyl, substituted or unsubstituted C 3 to C 8 cycloalkyl, substituted or unsubstituted C 6 to C 20 carbocyclic aryl, or substituted or unsubstituted C4 to C 20 heteroaryl having one to three heteroatoms wherein the heteroatoms are selected from sulfur, nitrogen, or oxygen; and
• R 11 is hydrogen, substituted or unsubstituted Ci to C 20 alkyl, substituted or unsubstituted Ci to C 2 o alkoxy, substituted or unsubstituted C 3 to C 8 cycloalkyl, substituted or unsubstituted C 3 to C 8 cycloalkoxy, substituted or unsubstituted carbocyclic Ce to C 2 o aryl, substituted or unsubstituted carbocyclic C 6 to C 20 aryloxy, substituted or unsubstituted C 4 to C 2 o heteroaryl having one to three heteroatoms wherein the heteroatoms are selected from sulfur, nitrogen, or oxygen or substituted or unsubstituted C 4 to C 20 heteroaryloxy having one to three heteroatoms wherein the heteroatoms are selected from sulfur, nitrogen, and oxygen.
• Examples of the substituents represented by R 9 , R 10 , R 11 and R 12 are set forth above in the descriptions of R, R 1 , R 2 and R 3
• the enamide starting material having formula 10 may be prepared using the methodology described by Schmidt et al., Synthesis 1984, 53-60; and Schmidt et al., Synthesis 1992, 487-490.
• the products having formula 9 generally are produced with very high enantioselectivity (>90% ee), with the particular enantiomer produced depending upon which enantiomer or diastereomer of phosphine-phosphoramidite compound 1 is used.
• Another preferred embodiment of our novel hydrogenation process involves the preparation of a compound having formula 11
• R 13 , R 14 , and R 15 are independently, hydrogen, substituted or unsubstituted, branched- or straight-chain CrC 2O alkyl, substituted or unsubstituted C 3 -C8 cycioalkyl, substituted or unsubstituted C 6 -C 2O carbocyclic aryl, or substituted or unsubstituted C 4 -C 20 heteroaryl having one to three heteroatoms wherein the heteroatoms are selected from sulfur, nitrogen, and oxygen.
• Itaconate starting materials of formula 12 are generally commercially available or can prepared by methods known to those skilled in the art.
• Compounds 11 typically are produced with very high enantioselectivity (>90% ee), with the particular enantiomer produced depending upon which enantiomer or diastereomer of phosphine- phosphoramidite compound 1 is used.
• reaction mixture was allowed to warm to ambient temperature overnight to completely consume 4a according to thin layer chromatography (tic) analysis.
• Heptane (30 mL) was added and the reaction mixture was filtered through celite and eluted with heptane and ethyl acetate. The resulting filtrate was stripped and the residue was filtered through a pad of flash silica gel and eluted with 1:9 ethyl acetate:heptane with 5% added triethylamine to afford 1.52 g (79%) of 2a.
• Toluene (5 ml_) was added to a 100-mL 3-necked flask which was cooled to ⁇ 5°C in an ice-water bath.
• Phosphorus trichloride (0.26 ml_; 3.0 mmol; 1.0 equiv) was added followed by triethylamine (0.50 mL; 3.6 mmol; 1.2 equiv).
• (R)- ⁇ /-Methyl-1-[(S)-2-(diphenylphosphino)ferrocenyl]ethylamine (4a)(1.28 g; 3.0 mmol) dissolved in 15 mL of toluene was added dropwise such that the temperature remained below 15°C.
• reaction mixture was stirred in ice-water for 15 minutes, then allowed to warm to ambient temperature for 45 minutes.
• the reaction mixture was cooled to ⁇ 5°C in ice-water and triethylamine (1.05 mL; 7.7 mmol; 2.5 equiv) was added followed by 4-methoxypheno! (745 mg; 6.0 mmol; 2 equiv) in 10 mL of toluene at a rate such that the temperature remained below 15°C.
• the reaction mixture was allowed to warm to ambient temperature overnight to almost completely consume 4a according to tic analysis.
• Heptane (30 mL) was added and the reaction mixture was filtered through celite and eluted with heptane and ethyl acetate.
• reaction mixture was cooled to ⁇ 5°C in ice-water and triethylamine (1.05 mL; 7.7 mmol; 2.5 equiv) was added followed by 4-trifluoromethylphenol (973 mg; 6.0 mmol; 2 equiv) in 10 mL of toluene at a rate such that the temperature remained below 15 0 C.
• the reaction mixture was allowed to warm to ambient temperature overnight to almost completely consume 4a according to tic analysis.
• Heptane (30 mL) was added and the reaction mixture was filtered through celite and eluted with heptane and ethyl acetate.
• Toluene (5 ml_) was added to a 100-mL 3-necked flask which was cooled to below -70 0 C in a dry ice-acetone bath.
• Phosphorus trichloride (174 ⁇ l_; 2.0 mmol; 1.0 equiv) was added followed by triethylamine (0.33 ml_; 2.4 mmol; 1.2 equiv).
• reaction mixture was cooled to below -70 0 C and triethylamine (0.70 ml_; 5.0 mmol; 2.5 equiv) was added followed by a warm toluene (15 ml_) solution of (R)- 1 ,1'-bi-2-naphthol (573 mg; 2.0 mmol; 1 equiv). This was washed in with 5 ml_ of toluene.
• the reaction mixture was allowed to warm to ambient temperature overnight to almost completely consume 4a according to tic analysis. Heptane (30 mL) was added and the reaction mixture was filtered and eluted with heptane and ethyl acetate.
• reaction mixture was stirred in dry ice-acetone for 1 hour, then allowed to warm to ambient temperature over 1.5 hours and stirred for 2 hours at ambient temperature.
• the reaction mixture was cooled to below -70°C and triethylamine (0.70 mL; 5.0 mmol; 2.5 equiv) was added followed by a warm toluene (15 mL) solution of (S)- 1 ,1'-bi-2-naphthol (573 mg; 2.0 mmol; 1 equiv). This was washed in with 5 mL of toluene.
• the reaction mixture was allowed to warm to ambient temperature overnight to almost completely consume 4a according to tic analysis.
• Bis(1 ,5- cyclooctadiene)rhodium trifluoromethanesulfonate (2.3 mg; 5 ⁇ mol; 0.01 equiv) and ligand 2a from Example 1 (3.9 mg; 6 ⁇ mol; 0.012 equiv) were combined and argon-degassed anhydrous THF (1.0 ml_) was added.
• Bis(1 ,5-cyclooctadiene)rhodium trifluoromethanesulfonate (2.3 mg; 5 ⁇ mol; 0.01 equiv) and ligand 2a from Example 1 (3.9 mg; 6 ⁇ mol; 0.012 equiv) were combined and argon- degassed anhydrous THF (1.0 mL) was added. This solution was stirred at 25°C under argon for 15 minutes and then added to the solution of 10b.
• Bis(1,5-cyclooctadiene)rhodium trifluoromethanesulfonate (2.3 mg; 5 ⁇ mol; 0.01 equiv) and ligand 2b from Example 2 (4.2 mg; 6 ⁇ mol; 0.012 equiv) were combined and argon- degassed anhydrous THF (0.75 ml_) was added. This solution was stirred at 25°C under argon for 15 minutes and then added to the solution of 10a.
• Bis(1 ,5-cyclooctadiene)rhodium trifluoromethanesulfonate (2.3 mg; 5 ⁇ mol; 0.01 equiv) and ligand 2c from Example 3 (4.7 mg; 6 ⁇ mol; 0.012 equiv) were combined and argon- degassed anhydrous THF (0.50 mL) was added.
• Bis(1,5-cyclooctadiene)rhodium trifluoromethanesulfonate (2.3 mg; 5 ⁇ mol; 0.01 equiv) and ligand 2c from Example 3 (4.7 mg; 6 ⁇ mol; 0.012 equiv) were combined and argon- degassed anhydrous THF (0.50 mL) was added. This solution was stirred at 25°C under argon for 15 minutes and then added to the solution of 10b.
• Bis(1 ,5-cyc!ooctadiene)rhodium trifluoromethanesulfonate (2.3 mg; 5 ⁇ mol; 0.01 equiv) and ligand 2c from Example 3 (4.7 mg; 6 ⁇ mol; 0.012 equiv) were combined and argon- degassed anhydrous THF (0.50 mL) was added. This solution was stirred at 25 0 C under argon for 15 minutes and then added to the solution of 10c.
• Chiral GC conditions Cyclosil-B [J&W Scientific] 30 m x 0.25 mm ID, 0.25 ⁇ m film thickness, 40-100 0 C 70°C/min, 100°C 15 min, 100-170°C 15°C/min, 17O 0 C 7 min, 6 psig He 6 min, 6-20 psig He 80 psig/min, 20 psig 22 min.
• t R (f?- ⁇ /-acetylalanine methyl ester) 19.36 min
• t R methyl 2-acetamidoacrylate
• Bis(1 ,5-cyclooctadiene)rhodium trifluoromethanesulfonate (2.3 mg; 5 ⁇ mol; 0.01 equiv) and ligand 2d from Example 4 (4.4 mg; 6 ⁇ mol; 0.012 equiv) were combined and argon- degassed anhydrous THF (0.50 mL) was added.
• Bis(1 ,5-cyclooctadiene)rhodium trifluoromethanesulfonate (2.3 mg; 5 ⁇ mol; 0.01 equiv) and ligand 2d from Example 4 (4.4 mg; 6 ⁇ mol; 0.012 equiv) were combined and argon- degassed anhydrous tetrahydrofuran (THF, 0.50 mL) was added.
• Bis(1,5- cyclooctadiene)rhodium trifluoromethanesulfonate (2.3 mg; 5 ⁇ mol; 0.01 equiv) and ligand 2d from Example 4 (4.4 mg; 6 ⁇ mol; 0.012 equiv) were combined and argon-degassed anhydrous THF (0.50 ml_) was added.
• Chiral GC conditions Chirasil L-Valine [VarianJ 25 m x 0.25 mm ID, film thickness 0.12 ⁇ m, 175°C 25 min, 20 psig He, t R (R-9d) 7.29 min, t R (S-9d) 7.76 min, t R (10d) 15.72 min.
• Bis(1 ,5- cyclooctadiene)rhodium trifluoromethanesulfonate (2.3 mg; 5 ⁇ mol; 0.01 equiv) and ligand 2d from Example 4 (4.4 mg; 6 ⁇ mol; 0.012 equiv) were combined and argon-degassed anhydrous THF (0.50 ml_) was added.
• Chiral GC conditions Chirasil L-Valine [Varian] 25 m x 0.25 mm ID, film thickness 0.12 ⁇ m, 185°C 30 min, 15 psig He, t R (R-9e) 22.02 min, t R (S-9e) 23.26 min.

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