# Patent

## Title
Nitrogen-containing monodentate phosphines and their use in catalysis

## Abstract

The present invention relates to novel nitrogen-containing monodentate phosphane ligands of formula (I) and to their use in catalytic reactions, especially in the improvement of haloaromatic compounds.

## Background
The present invention relates to novel ligands for transition metals, to their preparation and to their use in catalytic reactions, especially for the improvement of haloaromatic compounds.
Haloaromatic compounds, including especially chloroaromatic compounds, are intermediates which can be used variously in the chemical industry and which serve as preliminary products for the production of agricultural intermediates, pharmaceuticals, colourings, materials, etc. Vinyl halides are also important intermediates which are used as starting materials for polymers and in the production of the above-mentioned products.
Catalysts which are frequently employed for the functionalisation of haloaromatic compounds or vinyl halides to aromatic olefins or dienes (Heck reaction, Stille reaction), biaryls (Suzuki reaction), alkynes (Sonogashira reaction), carboxylic acid derivatives (Heck carbonylation), amines (Buchwald-Hartwig reaction) are palladium catalysts and nickel catalysts. Palladium catalysts are generally advantageous, owing to the wide applicability of coupling substrates with in some cases good catalytic activities, while nickel catalysts have advantages in the field of the reaction of chloroaromatic compounds and vinyl chlorides. Moreover, nickel is more readily available than palladium.
Palladium and nickel catalysts used within the scope of the activation and further improvement of haloaromatic compounds are both palladium(II) and/or nickel(II) complexes as well as palladium(0) and/or nickel(0) complexes, although it is known that palladium(0) and nickel(0) compounds are the actual catalysts of the reaction. In particular, according to information in the literature, coordinatively-unsaturated 14- and 16-electron palladium(0) and nickel(0) complexes stabilised with donor ligands such as phosphanes are formulated as the active species.
When iodides are used as starting materials in coupling reactions it is also possible to dispense with phosphane ligands. However, aryl iodides and vinyl iodides are starting materials which are scarcely available and therefore very expensive, and their reaction additionally yields stoichiometric amounts of iodine salt waste products. If other starting materials are used in the Heck reaction, such as aryl bromides or aryl chlorides, the addition of stabilising and activating ligands is necessary if catalytically effective reaction of the starting materials is to be possible.
The catalyst systems described for olefinations, alkynylations, carbonylations, arylations, aminations and similar reactions frequently have satisfactory catalytic turnover numbers (TON) only with uneconomical starting materials such as iodoaromatic compounds and activated bromoaromatic compounds. Otherwise, in the case of deactivated bromoaromatic compounds and, especially, in the case of chloroaromatic compounds, large amounts of catalyst—usually more than 1 mol. %—must generally be added in order to achieve industrially usable yields (>90%). Moreover, owing to the complexity of the reaction mixtures, simple recycling of the catalyst is not possible, so that recovery of the catalyst also gives rise to high costs, which generally stand in the way of industrial implementation. Furthermore, it is undesirable to work with large amounts of catalyst, especially when preparing active ingredients or preliminary products for active ingredients, because catalyst residues otherwise remain in the product in this case.
More recent active catalyst systems are based on cyclopalladated phosphanes (W. A. Herrmann, C. BroBmer, K. Öfele, C.-P. Reisinger, T. Priermeier, M. Beller, H. Fischer, Angew. Chem. 1995, 107, 1989; Angew. Chem. Int. Ed. Engl. 1995, 34, 1844) or mixtures of sterically demanding arylphosphanes (J. P. Wolfe, S. L. Buchwald, Angew. Chem. 1999, 111, 2570; Angew. Chem. Int. Ed. Engl. 1999, 38, 2413) or tri-tert.-butylphosphane (A. F. Littke, G. C. Fu, Angew. Chem. 1998, 110, 3586; Angew. Chem. Int. Ed. Engl. 1998, 37, 3387) with palladium salts or palladium. complexes.
However, chloroaromatic compounds can generally not be activated in an industrially satisfactory manner even using these catalysts. Accordingly, in order to achieve high yields, comparatively large, amounts of catalyst must be used. Therefore, despite all the further developments which have been made to catalysts in recent years, only a small number of industrial reactions of the arylation, carbonylation, olefination, etc. of chloroaromatic compounds have hitherto become known.
For the mentioned reasons, the object underlying the present invention was to provide novel ligands and catalysts which are suitable for large-scale applications, are readily accessible and convert chloro- and bromo-aromatic compounds as well as corresponding vinyl compounds to the respective coupling products in high yield and with high purity, with high catalyst productivity.
This object is achieved according to the invention by novel phosphane ligands of formula (I)




wherein

    X independently of Y represents a nitrogen atom or a C—R2 group and
    Y independently of X represents a nitrogen atom or a C—R9 group,
    R1 for each of the two R1 groups independently of the other represents a radical selected from the group C1-C24-alkyl,
    
        C3-C20-cycloalkyl, which includes especially both monocyclic and also bi- and tri-cyclic cycloalkyl radicals,
        C5-C14-aryl, which includes especially the phenyl, naphthyl, fluorenyl radical,
        C2-C13-heteroaryl, wherein the number of hetero atoms, selected from the group N, O, S, may be from 1 to 2,
        wherein the two radicals R1 may also be linked to one another, there preferably being formed a 4- to 8-membered saturated, unsaturated or aromatic ring.
        The above-mentioned radicals R1 may themselves each be mono- or poly-substituted. These substituents, independently of one another, may be hydrogen, C1-C20-alkyl, C2-C20-alkenyl, C3-C8-cycloalkyl, C2-C9-hetero-alkyl C5-C10-aryl, C2-C9-heteroaryl, wherein the number of hetero atoms, especially from the group N, O, S, may be from 1 to 4, C1-C20-alkoxy, preferably C1-C10-alkoxy, particularly preferably OMe, C1-C10-halo-alkyl, preferably trifluoromethyl, hydroxy, secondary, tertiary amino groups of the forms NH—(C1-C20-alkyl), NH—(C5-C10-aryl), N(C1-C20-alkyl)2, N(C1-C20-alkyl) (C5-C10-aryl), N(C5-C10-aryl)2, N(C1-C20-alkyl/C5-C10-aryl3)3+, NH—CO—C1-C20-alkyl, NH—CO—C5-C10-aryl, carboxylato of the forms COOH and COOQ (wherein Q represents either a monovalent cation or C1-C8-alkyl), C1-C6-acyloxy, sulfinato, sulfonato of the forms SO3H and SO3Q (wherein Q represents either a monovalent cation, C1-C20-alkyl or C5-C10-aryl) tri-C1-C6-alkylsilyl, especially SiMe3,
        wherein two of the mentioned substituents may also be bridged with one another, there preferably being formed a 4- to 8-membered ring which can be further substituted preferably by linear or branched C1-C10-alkyl, C6-aryl, benzyl, C1-C10-alkoxy, hydroxy or benzyloxy groups.
    
    
    R2-R9 represent a hydrogen, alkyl, alkenyl, cycloalkyl, aromatic or heteroaromatic aryl, O-alkyl, NH-alkyl, N-(alkyl)2, O-(aryl), NH-(aryl), N-(alkyl) (aryl), O—CO -alkyl, O—CO-aryl, F, Si(alkyl)3, CF3, CN, CO2H, COH, SO3H, CONH2, CONH(alkyl), CON(alkyl)2, SO2(alkyl), SO(alkyl), SO(aryl), SO2(aryl), SO3(alkyl), SO3(aryl), S-alkyl, S-aryl, NH—CO(alkyl), CO2(alkyl), CONH2, CO(alkyl), NHCOH, NHCO2(alkyl), CO(aryl), CO2(aryl) radical,
    
        wherein two or more adjacent radicals, each independently of the other(s), may also be linked to one another so that a condensed ring system is present and
        wherein in R2 to R9 alkyl represents a hydrocarbon radical having from 1 to 20 carbon atoms which may in each case be linear or branched, alkenyl represents a mono- or poly-unsaturated hydrocarbon radical having from 2 to 20 carbon atoms which may in each case be linear or branched, and cycloalkyl represents a hydrocarbon having from 3 to 20 carbon atoms, wherein the alkyl, alkenyl and cycloalkyl groups may also carry further substituents as defined for R1. Preferred substituents in this connection are selected from the group Br, Cl, F, (C1-C12)-alkyl, O—(C1-C12)-alkyl, phenyl, O-phenyl, NH((C1-C12)-alkyl), N((C1-C12)-alkyl)2, and
        aryl represents a 5- to 14-membered aromatic radical in which from one to four carbon atoms may also be replaced by hetero atoms from the group nitrogen, oxygen and sulfur so that a 5- to 14-membered hetero-aromatic radical is present and wherein the aryl or heteroaryl radical may carry further substituents as defined for R1, preferred substituents being selected from the group Br, Cl, F, (C1-C12)-alkyl, O—(C1-C12) -alkyl, phenyl, O-phenyl, NH2, NH((C1-C12)-alkyl), N((C1-C12)-alkyl)2.
    
    


The mentioned alkyl radicals have preferably from 1 to 10 carbon atoms, particularly preferably from 1 to 5. The alkenyl radicals have preferably from 2 to 10 carbon atoms, particularly preferably from 2 to 5. The cycloalkyl radicals have preferably from 3 to 8 carbon atoms. The aryl radicals have preferably from 6 to 10 carbon atoms, the heteroaryl radicals from 4 to 9.
Preference is given to ligands wherein X is CR2 and Y is CR9, yielding compounds of formula (II)




wherein the radicals R1 to R9 are as defined above. In a further preferred embodiment, X is nitrogen and Y is a CR9 group.

Preferred ligands of formula (I) or (II) carry at least one radical R1 selected from the group consisting of phenyl, C1-C10-alkyl, cyclopentyl, cyclohexyl, cycloheptyl, 1-adamantyl, 2-adamantyl, 5H-dibenzophospholyl, 9-phospha-bicyclo[3.3.1]nonanyl, 9-phosphabicyclo[4.2.1]nonanyl radicals. Examples of preferred C1-C10-alkyl- radicals are methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methyl-propyl, 1,1-dimethylethyl, n-pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 2,2-dimethylpropyl, 1-ethyl-propyl, n-hexyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methyl-pentyl, 1,1-dimethylbutyl, 1,2-dimethylbutyl, 1,3-dimethyl-butyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethyl-butyl, 1-ethylbutyl, 2-ethylbutyl, 1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl, 1-ethyl-1-methylpropyl, n-heptyl, n-octyl, n-nonyl, n-decyl, particular preference being given especially to the isopropyl radical and the tert-butyl radical.
Preferred radicals R2 to R9 are selected from the group hydrogen, C1-C10-alkyl, C2-C10-alkenyl, C1-C10-haloalkyl, C3-C8-cycloalkyl, C6-C10-aryl, which includes especially also phenyl, naphthyl, fluorenyl, and C2-C6-heteroaryl, wherein from 1 to 3 nitrogen atoms or an oxygen or sulfur atom may be present as hetero atom, and wherein two adjacent radicals R2 to R9 may be bridged with one another, there preferably being formed a 4- to 8-membered, preferably aromatic ring.
The ligands according to the invention can be prepared by reacting the corresponding phenylpyrrole derivative in the presence of a strong base, such as, for example, an alkyl-lithium compound, and subsequently adding a halophosphane, in accordance with the following reaction scheme, which is given by way of example




According to the invention, the novel phosphane ligands are used as catalysts in combination with transition metal complexes or transition metal salts of sub-group VIII of the periodic system of the elements, such as, for example, palladium, nickel, platinum, rhodium, iridium, ruthenium, cobalt. The ligands according to the invention can generally be added in situ to corresponding transition metal precursor compounds and accordingly used for catalytic applications. However, it may occasionally be advantageous for specific mono-, di-, tri- or tetra-phosphane complexes of the mentioned transition metals to be prepared first and subsequently used for catalysis reactions. The catalytic activity can thereby be increased further in some catalyst systems.
As transition metal compounds there are preferably used palladium or nickel compounds and particularly preferably palladium compounds.
The ligands according to the invention are generally added in situ preferably to nickel(II) or palladium(II) salts or to nickel(II), palladium(II) or nickel(0) or palladium(0) complexes. Preferred palladium complexes are, for example, palladium(II) acetate, palladium(II) chloride, palladium(II) bromide, lithium tetrachloropalladate(II), palladium(II) acetylacetonate, palladium(0) -dibenzylidene-acetone complexes, palladium(0) tetrakis(triphenyl-phosphane), palladium(0) bis(tri-o-tolylphosphane), palladium(II) propionate, palladium (II) bis(triphenyl-phosphane) dichloride, palladium(0) diallyl ether complexes, palladium(II) nitrate, palladium(II) chloride bis(acetonitrile), palladium(II) chloride bis(benzo-nitrile).
In catalytic applications, the phosphane ligand is generally used in excess relative to the transition metal. The ratio of transition metal to ligand is preferably from 1:1 to 1;1000. Ratios of transition metal to ligand of from 1:1 to 1:100 are particularly preferred. The exact transition metal/ligand ratio to be used depends on the concrete application, but also on the amount of catalyst used. Accordingly, it is generally customary to use low transition metal/ligand ratios at very low transition metal concentrations (<0.01 mol. %) than at transition metal concentrations of from 0.5 to 0.01 mol. % transition metal.
The catalysts are preferably used at temperatures of from 20 to 200° C.; in many cases, it has proved advantageous to work at temperatures of from 30 to 180° C., preferably from 40 to 160° C. The ligands can also be used without any loss of activity in reactions under pressure, reactions usually being carried out only up to a pressure of 100 bar, but preferably in the range of from normal pressure to 60 bar.
When carrying out catalytic reactions using ligands of formula (I), high turnover rates (TON) can be achieved with a low catalyst concentration. The transition metal is preferably used in a ratio of from 5 mol. % to 0.001 mol. %, particularly preferably from 0.5 mol. % to 0.01 mol. %, relative to the substrate.
The phosphane ligands prepared in accordance with the invention have proved suitable especially as the ligand component for the catalytic preparation of arylated olefins (Heck reactions), biaryls (Suzuki reactions), α-aryl ketones and amines from aryl halides or vinyl halides. However, it is obvious to the person skilled in the art that the novel catalyst systems can also be used to catalyse other transition-metal-catalysed reactions, such as metathesis or hydrogenations of double bonds or carbonyl compounds, but especially palladium- and nickel-catalysed carbonylations of aryl halides, alkynylations using alkynes (Sonogashira couplings), cross-couplings using organometallic reagents, such as, for example, zinc reagents or tin reagents.
A particular advantage of the ligands according to the invention is the high degree of activity induced by the ligands in the activation of readily available but inert chloroaromatic compounds. The described catalyst and ligand systems can accordingly be used for large-scale purposes.
The phosphanes prepared in accordance with the invention can be used in the preparation of aryl olefins, dienes, diaryls, benzoic acid derivatives, acrylic acid derivatives, arylalkanes, alkynes, amines. The compounds so prepared are used, for example, as UV absorbers, as intermediates for pharmaceuticals and agrochemicals, as ligand precursors for metallocene catalysts, as perfumes, as active ingredients having biological activity and as structural units for polymers.


IMPLEMENTATION EXAMPLES
General
Reactions of compounds sensitive to air were carried out in an argon-filled glove-box or in standard Schlenk tubes. The solvents tetrahydrofuran (THF), diethyl ether and dichloromethane were degassed and rendered absolute by means of a solvent-drying installation (Innovative Technologies) by filtration through a column packed with activated aluminium oxide. Toluene and pentane were additionally freed of oxygen using a column packed with a copper catalyst.
The Examples which follow serve to explain the invention without limiting it thereto.
Preparation of Ligands 1 to 3 (L1 to L3):
10 mmol. of phenylpyrrole are dissolved under argon in 20 ml of absolute hexane. 10 mmol. of TMEDA and 10 mmol. of n-BuLi (1.6 M in hexane) are added at room temperature. After three hours' heating under reflux, a yellow suspension is obtained. It is cooled to room temperature, and 10 mmol. of C1-PR12 are slowly added thereto. After reacting for one hour under reflux, hydrolysis is carried out at room temperature using 15 ml of degassed water. The organic phase is transferred to a separating funnel, under argon, with the aid of a cannula. The aqueous phase is extracted twice using 15 ml of hexane each time. The hexane fractions are likewise transferred to the separating funnel. The combined organic phases are washed with 15 ml of degassed water and dried over degassed sodium sulfate. The solvents are distilled off and the viscous residue is dissolved in methanol with heating. After one day at room temperature, the mixture is cooled for four hours at 0° C. The resulting white solid is filtered off and dried in vacuo (purity 90-95%).
Yields:


    PR12=PCy2 72% (31P—NMR: −28.0 ppm) (L1; N—PHOS-Cy):
    PR12=PPh2 64% (31P—NMR: −29.8 ppm) (L2; N—PHOS-Ph)
    PR12=PtBu240% (31P—NMR: 3.6 ppm) (L3; N—PHOS-tBu)


CATALYSIS EXAMPLES 1 to 32
Suzuki Couplings
1.25 mmol. of phenylboronic acid and 2.00 mmol. of base are weighed into 2.5 ml glass bottles. These bottles are purged with argon and sealed. All further stock solutions are prepared under argon.

    Solution S-1: 147 mmol. of 2-chlorotoluene, 58 mmol. of tetradecane, 155 ml of abs. toluene
    Solution S-2: 150 mmol. of 4-chloroanisole, 57 mmol. of tetradecane, 154 ml of abs. toluene
    Solution M-1: 0.073 mmol.pd of palladium(II) acetate, 49 ml of abs. toluene
    Solution M-2: 0.065 mmol.pd of tris-(dibenzylideneacetone)-dipalladium(0), 49 ml of abs. toluene
    Solution L-1: 0.04 mmol. of N—PHOS-Cy (L1), 10 abs. toluene
    Solution L-2: 0.08 mmol. of N—PHOS-tBu (L3), 21 abs. toluene


The following solutions are mixed under Ar and stirred for about 1 hour at room temperature (reaction metal precursor with ligand):














Ligand
Metal precursor


















M-L-1
 5.0 ml L-1
 7.5 ml M-1


M-L-2
 5.0 ml L-1
 7.5 ml M-2


M-L-3
10.5 ml L-2
16.0 ml M-1


M-L-4
10.5 ml L-2
16.0 ml M-2









A Vantage synthesizer is used to pipette the following amounts of the resulting solutions into the Vantage vials:

    
    
        1. 1.25 ml of S-1 (No. 1-8), (No. 17-24) 1.25 ml of S-2 (No. 9-16), (No. 25-32)
        2. 1.25 ml of M-L-1 (No. 1-16) or 1.25 ml of M-L-2 (No. 17-32).
    
    


Using the Vantage mixing/heating unit, the Vantage vials so filled are heated for 4.0 hours at 110° C. (Vantage setting) with shaking (1000 rpm) (heating phase 0.5 h/internal temperature about 120° C.).
After the reaction, 1.0 ml of each reaction solution is filtered over silica gel. The solution so obtained is analysed by means of GC. The yields of the individual conversions are summarised in Table 1.







TABLE 1







Summary of the results of Catalysis Examples 1


to 32


















Base
















Starting


Ligand

Eq. to




material

Metal precursor
eq. to

starting
Yield















No.
[mmol.]
Lig.
Name
mol. %pd
Pd
Name
material
(%)


















1
1.0
L-1
Pd(OAc)2
0.1
2
K3PO4
2
83.8/89.1


2
1.0
L-1
Pd(OAc)2
0.1
2
K2CO3
2
78.4/85.0


3
1.0
L-1
Pd(OAc)2
0.1
2
NaOAc
2
9.1/7.8


4
1.0
L-1
Pd(OAc)2
0.1
2
Cs2CO3
2
51.0/60.8


5
1.0
L-1
Pd2(dba)3
0.1
2
K3PO4
2
94.0/89.8


6
1.0
L-1
Pd2(dba)3
0.1
2
K2CO3
2
94.8/93.0


7
1.0
L-1
Pd2(dba)3
0.1
2
NaOAc
2
34.4/35.2


8
1.0
L-1
Pd2(dba)3
0.1
2
Cs2CO3
2
57.7/53.7


9
1.0
L-1
Pd(OAc)2
0.1
2
K3PO4
2
60.3/64.8


10
1.0
L-1
Pd(OAc)2
0.1
2
K2CO3
2
28.0/40.5


11
1.0
L-1
Pd(OAc)2
0.1
2
NaOAc
2
3.6/3.7


12
1.0
L-1
Pd(OAc)2
0.1
2
Cs2CO3
2
36.3/10.0


13
1.0
L-1
Pd2(dba)3
0.1
2
K3PO4
2
84.8/95.8


14
1.0
L-1
Pd2(dba)3
0.1
2
K2CO3
2
65.5/68.2


15
1.0
L-1
Pd2(dba)3
0.1
2
NaOAc
2
23.5/24.0


16
1.0
L-1
Pd2(dba)3
0.1
2
Cs2CO3
2
34.7/27.2


17
1.0
L-2
Pd(OAc)2
0.1
2
K3PO4
2
61.4/84.5


18
1.0
L-2
Pd(OAc)2
0.1
2
K2CO3
2
52.5/50.1


19
1.0
L-2
Pd(OAc)2
0.1
2
NaOAc
2
19.4/16.5


20
1.0
L-2
Pd(OAc)2
0.1
2
Cs2CO3
2
18.1/12.8


21
1.0
L-2
Pd2(dba)3
0.1
2
K3PO4
2
98.9/96.1


22
1.0
L-2
Pd2(dba)3
0.1
2
K2CO3
2
93.4/91.3


23
1.0
L-2
Pd2(dba)3
0.1
2
NaOAc
2
17.4/6.1 


24
1.0
L-2
Pd2(dba)3
0.1
2
Cs2CO3
2
36.5/31.7


25
1.0
L-2
Pd(OAc)2
0.1
2
K3PO4
2
83.5/97.3


26
1.0
L-2
Pd(OAc)2
0.1
2
K2CO3
2
74.1/60.1


27
1.0
L-2
Pd(OAc)2
0.1
2
NaOAc
2
33.2/39.4


28
1.0
L-2
Pd(OAc)2
0.1
2
Cs2CO3
2
69.6/66.4


29
1.0
L-2
Pd2(dba)3
0.1
2
K3PO4
2
91.5/99.6


30
1.0
L-2
Pd2(dba)3
0.1
2
K2CO3
2
81.7


31
1.0
L-2
Pd2(dba)3
0.1
2
NaOAc
2
26.6/24.5


32
1.0
L-2
Pd2(dba)3
0.1
2
Cs2CO3
2
71.5/56.7









CATALYSIS EXAMPLES 33 to 59
Suzuki Reaction of Aryl Chlorides with Phenylboronic Acid/-pyrrolylphosphanes

R—Ar—Cl+PhB(OH)2→R—Ar—Ph

Reagents: 3 nmol. of ArCl, 4.5 mmol. of PhB(OH)2, 6 mmol. of K3PO4, Pd(OAc)2, Pd/L=1:2, 6 ml of toluene, 20 hours. The reaction is carried out as a one-pot reaction under protecting gas. Working-up is carried out with 10 ml of each of methylene chloride and 1N sodium hydroxide solution. The reaction is monitored by means of GC, internal GC standard: hexadecane.
The starting materials used and the results of the conversions are summarised in Table 2.







TABLE 2







Summary of the results of Catalysis Examples 33


to 59




















Yield






Conc.


(aver-





[mol.
T
C
aged)


No.
R
Ligand
%]
[° C.]
[%]
[%]
TON










Aromatic compounds














33
4-CF3
PtBu2
0.01
60
71-84
 74
7400


34
4-COMe
PtBu2
0.01
60
100
100
10,000


35
4-CN
PtBu2
0.01
60
100
100
10,000


36
H
PtBu2
0.01
60
83-98
 96
9600


37
4-Me
PtBu2
0.01
60
98-100
 99
9900


38
4-Ome
PtBu2
0.01
60
73-89
 80
8000


39
2-CF3
PtBu2
0.05
60
 91


40
2-CF3
PCy2
0.05
60
 99
 95


41
2-CF3
PAd2
0.05
60
 75


42
2-COMe
PtBu2
0.05
60
78-84
 85


43
2-COMe
PCy2
0.05
60
 55


44
2-COMe
PAd2
0.05
60
 70


45
2-CN
PtBu2
0.05
60
100
100
2000


46
2-CN
PCy2
0.05
60
100
100
2000


47
2-CN
PAd2
0.05
60
100
 99
1980


48
2-Me
PtBu2
0.01
60
80-87
 81
8100


49
2-Ome
PtBu2
0.01
60
97-100
 97
9700


50
2-F
PtBu2
0.01
60
100
 97
9700


51
2,6-Me2
PtBu2
0.05
60
20-22
 16
320


52
2,6-Me2
PCy2
0.05
60
 76
 72
1440


53
2,6-Me2
PAd2
0.05
60
 18
 15
300







Heterocycles














54
3-chloro-
PtBu2
0.01
60
99-100
 99
9900



pyridine


55
2-chloro-
PtBu2
0.05
60
100
 87
1740



quinoline


56
5-chloro-
PtBu2
0.05
100
97-100
 90



indole


57
2-chloro-
PtBu2
0.05
100
 99
 0a)
0



benzoxazole


58
3-chloro-
PtBu2
0.05
100
 11
 5
100



thiophene


59
5-chloro-
PtBu2
0.05
100
100
 99
1980



furfural





a)unknown (not visible in the GC) decomposition products. Both starting material and product withstand the basic working-up undamaged. Decomposition (>60%) but scarcely any product (<10%) is observed even at a reaction temperature of 60° C.






EXAMPLES 60 to 64
Examples of Ligand Syntheses
EXAMPLE 60
Synthesis of N-phenyl-2-(di-1-adamantyl-phosphino)pyrrole




1.6 ml of TMEDA (15 mmol.) are added to a suspension of 1.43 g (10 mmol.) of N-phenylpyrrole in 30 ml of hexane. 6.25 ml of 1.6 molar n-butyllithium solution (10 mmol.) are added at room temperature. The mixture is then heated for 2.5 hours at reflux temperature (solution 1). In another flask, 3.36 g (10 mmol.) of di-1-adamantylchlorophosphane are mixed with 40 ml of hexane and heated to 76° C. (solution 2). The boiling solution 1 is then slowly transferred into solution 2, which is at 76° C., by means of a cannula. The mixture is then boiled for a further 2 hours at reflux, the solution is cooled, and 20 ml of water are added thereto. The organic phase is filtered off over magnesium sulfate. The solution is concentrated in vacuo; 15 ml of toluene are added thereto, and the mixture is heated to 60° C. and then cooled. After one day at room temperature, the product is filtered off. Yield: 3.3 g (75%).
31P NMR (161 MHz, CDCl3): δ=−4.5.
1H NMR (400 MHz, CDCl3): δ=1.7 (bs, 16H), 1.7-2.0 (m, 22H), 6.4 (dd, J1=8.6, 12.8, J2=3.5, 1H), 6.75 (dd, J1=3.5, J2=1, 1H), 6.9-7.0 (m, 1H), 7.25-7.3 (m, 2H), 7.35-7.45 (m, 3H).
13C NMR (100.6 MHz, CDCl3): δ=28.6 (d, JPC=11.5), 37, 37.5 (d, JPC=17.2), 41.6 (d, JPC=11.5), 108.2, 119.5 (d, JPC=4.7), 125.8, 126 (d, JPC=10.8), 127.3, 128.2, 128.3 (d, JPC=3.8), 141.6 (d, JPC=1.9).
MS: m/z (%): 443 (68), 308 (13), 172 (14), 135 (100), 107 (7), 93 (19), 79 (17).
HRMS: C30H38NP: calc. 443.2742; found 443.26775.
EXAMPLE 61
Synthesis of 1-mesityl-2-(dicyclohexyl-phosphino)imidazole




1.6 ml of TMEDA (15 mmol.) are added to a suspension of 1.86 g (10 mmol.) of N-mesitylimidazole in 30 ml of hexane. 6.25 ml of 1.6 molar n-butyllithium solution (10 mmol.) are added at room temperature. The mixture is then heated for 2.5 hours at reflux temperature (solution 1). In another flask, 2.2 ml (10 mmol.) of dicyclohexylchlorophosphane are mixed with 20 ml of hexane and heated to 60° C. (solution 2). The boiling solution 1 is then slowly transferred into solution 2, which is at 60° C., by means of a cannula. The mixture is then boiled for a further 1 hour at reflux, the solution is cooled, and 20 ml of degassed water are added thereto. The organic phase is filtered off over magnesium sulfate. The solution is concentrated in vacua; 30 ml of pentane are added thereto, and the mixture is boiled for 1 hour at reflux. The product precipitates in crystalline form at −30° C. and is filtered off while cold. Yield: 2.48 g (65%)
31P NMR (161 MHz, CDCl3): δ=−18.9.
1H NMR (400 MHz, CDCl3): δ=0.9-1.2 (m, 11H), 1.5-1.7 (m, 11H), 1.9 (s, 6H), 1.9-2.0 (m, 2H), 2.2 (s, 3H), 6.8-6.9 (m, 3H), 7.3 (S, 1H).
13C NMR (100.6 MHz, CDCl3): δ=18.5, 20.9, 26.9, 27.5, 27.7 (d, J=9.5), 30.4 (d, J=14.3), 30.9 (d, J=10.5), 34.6 (d, J=9.5), 122.7, 129.2, 131.5, 134.9, 135.5, 138.2, 147.5 (d, J=16.2).
MS; m/z (%): 382 (11), 299 (100), 217 (24), 202 (7), 185 (27), 83 (7), 55 (21).
EXAMPLE 62
Synthesis of N-(2-methoxyphenyl)-2-(dicyclo-hexylphosphino)pyrrole


    a) Synthesis of N-(2-methoxyphenyl)pyrrole






Lit.: Faigl, F.; Fogassy, K.; Thuner, A.; Toke, L.; Tetrahedron 1997, 53, 4883.
10.95 g (83 mmol.) of 1 and 4.7 g (38 mmol.) of 2 are refluxed for 2 hours in 10 ml of glacial acetic acid. The colour of the solution changes from yellow through red to black. The mixture is then diluted with 75 ml of distilled water and extracted twice with 100 ml of CH2Cl2. Na2CO3 is added to the black organic solutions. After filtration and concentration (20 mbar, 50° C.), a black oil is obtained and is distilled in vacuo. Yield: 4.45 g (25.7 mmol.; 75%).
1H NMR (25° C., CDCl3): δ (ppm)=3.8 (s, 3H), 6.3 (t, J=2.2 Hz, 2H), 7.0 (m, 4H), 7.3 (m, 2H).

    b) Synthesis of N-(2-methoxyphenyl)-2-(dicyclohexyl-phosphino)pyrrole






3.14 ml (15 mmol.) of N,N,N′,N′,N′′-pentamethyldiethylene-triamine (PMDTA) are added to a solution of 1.73 g (10 mmol.) of 1 in 30 ml of hexane. A solution (1.6 M in hexane) of n-BuLi (6.25 ml, 10 mmol.) is added dropwise. After 3 hours under reflux (75° C.), the colour of the solution has changed from yellow to black. Without cooling this mixture, 2.2 ml (10 mmol.) of chlorodicyclohexyl-phosphane dissolved in 20 ml of hexane are added dropwise. Refluxing is carried out for a further one hour. The colour of the solution lightens to orange, and a white precipitate forms. After cooling to room temperature, 30 ml of water are added to the mixture. The orange organic phase is extracted 3 times using 20 ml of hexane each time. The combined organic phases are washed with 10 ml of water and filtered over Na2SO4. The solvent is removed in vacuo (45° C.). The viscous orange residue is refluxed for 30 minutes in 30 ml of MeOH. On cooling to RT, the product precipitates and is filtered off (1.1 g, 30%).
1H NMR (25° C., C6D6): δ (ppm)=1.1-1.9 (m, 22H), 3.2 (s, 3H), 7.0 (m, 4H), 6.5-7.2 (m, 3H).
13C NMR (25° C., C6D6): δ (ppm)=27.2, 27.7, 27.8, 29.6, 30.9, 34.9, 55.1, 109.8, 111.8, 116.5, 116.6, 120.2, 123.6, 129.3, 130.9, 136.3, 156.0.
31p NMR (25° C., C6D6): δ (ppm) −26.8.
EXAMPLE 63
Synthesis of N-phenyl-2-(dicyclohexyl-phosphino)indole


    a) Synthesis of N-phenylindole






Lit.: Synthesis: Klapars, A.; Antilla, J.; Huang, X.; Buchwald, S. J. Am. Chem. Soc. 2001, 123, 7721. Analysis: (a) Nishio, T. J. Org. Chem. 1988, 53, 1323. (b) Belier, M.; Breindl, C.; Riermeier, T.; Tillack, A. J. Org. Chem. 2001, 66, 1403.
0.19 g (0.1 nmol.) of CuI, 2.34 g (20 mmol.) of 1, 8.82 g (42 mmol.) of K3PO4, 0.48 ml (4 mmol.) of 1,2-diaminocyclo-hexane and 3.16 ml (30 mmol.) of 2 are stirred for 24 hours at 110° C. in 20 ml of dry dioxane. The mixture is then diluted with 50 ml of ethyl acetate. The violet precipitate is filtered off over silica gel, yielding a yellow solution, which is concentrated in vacuo (20 mbar, 50° C.). The orange oil that remains is purified by column chromatography (silica gel, hexane/ethyl acetate 98/2). Yield: 3.0 g (15.5 mmol.; 75%).
1H NMR (25° C., CDCl3): δ (ppm)=6.45 (m, 1H), 6.9-7.5 (m, 10H).
13C NMR (25° C., CDCl3): δ (ppm)=104.1, 111.1, 120.9, 121.7, 122.9, 124.9, 126.9, 128.5, 129.9, 130.1, 130.6, 132.1, 136.4, 140.3.

    b) Synthesis of N-phenyl-2-(dicyclohexylphosphino)indole






1.6 ml (15 mmol.) of TMEDA are added to 1.93 g (10 mmol.) of 1 in 30 ml of hexane. A solution (1.6 M in hexane) of n-BuLi (6.25 ml, 10 mmol.) is added dropwise. After 3 hours, reflux (75° C.), the colour has deepened from yellow to orange. Without cooling, a solution of 2.2 ml (10 mmol.) of chlorodicyclohexylphosphane in 20 ml of hexane is added dropwise. Refluxing is carried out for a further one hour, the colour of the mixture lightening again and a white solid precipitating. After cooling, 30 ml of water are added to the mixture. The aqueous phase is extracted 3 times using 20 ml of hexane each time. The combined organic phases are washed with 10 ml of water, dried over Na2SO4 and concentrated in vacuo (45° C.). The yellow residue is boiled for 30 minutes in 30 ml of MeOH. After cooling to RT, the resulting product is filtered off (660 mg, 17%).
31P NMR (25° C., C6D6): δ (ppm)=−24.8.
EXAMPLE 64
Synthesis of N-(naphthyl)-2-(dicyclohexyl-phosphino)pyrrole


    a) Synthesis of N-naphthylpyrrole






Lit.: Analysis: (a) Paredes, E.; Biolatto, B.; Kneeteman, M.; Mancini, P. Tetrahedron Lett. 2000, 41, 8079. (b) Gross, H. Chem. Ber. 1962, 95, 2270.
10.95 g (83 mmol.) of 1 are added to a violet solution of 5.44 g (38 mmol.) of 2 in 10 ml of glacial acetic acid. The resulting brown solution is refluxed for 3 hours under argon (120° C.), whereupon its colour changes to black. The solution is concentrated to half the volume in vacuo (20 mbar, 50° C.) before being hydrolysed with 20 ml of water. The organic phase is extracted with CH2Cl2 (3×30 ml), dried over Na2SO4 and concentrated (20 mbar, 50° C.), there being obtained a black oil which is purified by column chromatography (silica gel, hexane/ethyl acetate 85/15). Yield: 3.53 g (18.3 mmol.) of a red oil which, crystallises at −25° C. (pink crystals).
1H NMR (25° C., CDCl3): δ (ppm)=6.3 (t, J=2.2 Hz, 2H), 6.7 (t, J=2.2 Hz, 2H), 6.9-7.2 (m, 4H), 7.3 (d, 8.1 Hz, 1H), 7.4 (d, 8.1 Hz, 1H), 7.7 (d, 8.1 Hz, 1H).
13C NMR (25° C., CDCl3): δ (ppm)=110.0, 123.6, 123.8, 123.9, 125.7, 126.9, 127.4, 128.2, 130.7, 134.9, 139.0.
Elemental analysis: found (%) C 86.7 (th: 87.0), H 5.89 (5.70), N 7.29 (7.30).

    b) Synthesis of N-(naphthyl)-2-(dicyclohexylphosphino)-pyrrole






1.6 ml (15 mmol.) of TMEDA are added to a solution of 1.93 g (10 mmol.) of 1 in 30 ml of hexane. A solution (1.6 M in hexane) of n-BuLi (6.25 ml, 10 mmol.) is added dropwise. After 3 hours reflux (75° C.), the colour has changed from orange through green to black. Without cooling, a solution of 2.2 ml (10 mmol.) of chlorodicyclo-hexylphosphane in 20 ml of hexane is added dropwise and refluxing is carried out for a further one hour. The colour of the solution changes to yellow, and a white precipitate forms. After cooling to RT, 30 ml of water are added to the mixture. The aqueous phase is extracted 3 times using 20 ml of hexane each time. The combined organic phases are washed with 10 ml of water, dried over Na2SO4 and concentrated in vacuo (45° C.). The orange oil that remains is refluxed for 30 minutes in 30 ml of MeOH (60° C.). On cooling to −25° C., the product precipitates in the form of a yellow solid and is filtered off (0.9 g, 24%).
31p NMR (25° C., C6D6): δ (ppm)=−23.3.
EXAMPLE 65
Ligands:




General Procedure:

In a three nacked 100 ml round bottom flask with reflux condenser, N-arylpyrrole (or N-arylindole or N-arylimidazole) (10 mmol) was dissolved in 20 ml of freshly distilled n-hexane under argon. TMEDA (15 mmol) was added followed by n-BuLi (10 mmol, 1.6 M in hexane) at room temperature. The reaction mixture was refluxed for 3 h. A solution of the corresponding chlorophosphine (10 mmol in 5 ml hexane) was slowly added via syringe. The mixture was further refluxed for 1 h. After cooling to room temperature, degassed water (15 ml) was added and the mixture was stirred to get a clear solution. The aqueous layer was extracted with hexane (2×15 ml) and the combined organic layers were washed with degassed water (15 ml). The solution was dried over Na2SO4 and concentrated at 45° C. to get a viscous liquid which was recrystallized from methanol or toluene.
EXAMPLE 66
Catalytic Amination of Aryl Chlorides
A 30 mL pressure tube was loaded with Pd(OAc)2 (0.025 mol), the ligand (0.050 mmol), NaOtBu (6.0 mmol) and was purged by argon for 30 minutes. Then, were successively added under argon, toluene (5 mL), the aryl chloride (5 mmol) and the amine (6 mmol). The mixture was stirred under argon at 120° C. for 20 hours. After reaction, it was diluted with diethylether (15 mL) and washed with water (10 mL). After extraction, the organic phase was dried over MgSO4, concentrated under vacuum and the final product was isolated by column chromatography (silicagel, hexane/ethyl acetate 90/10). Alternatively, diethyleneglycol-di-n-butylether or hexadecane was added as internal standard, and quantitative analysis was done by gas chromatography.







TABLE 1







Amination of chloro-benzene with aniline using


ligands 1 to 10: comparison of the activity.













Conv.
Yield



Entry
Ligand
[%][a]
[%][a]
T.O.N.














1




2
1
2


 


2




11
9
18


 


3




97
68
136


 


4




77
76
152


 


5




91
87
174


 


6




69
68
136


 


7




62
62
124


 


8




13
9
18


 


9




94
87
174


 


10




49
46
92





5 mmol aryl chloride, 6 mmol amine, 6 mmol NaOtBu, 0.5 mol % Pd(OAc)2, 1 mol % ligand, 5 mL toluene, 48 h, 120° C.


[a]Average of 2 runs, determined by GC using diethyleneglycol di-n-butyl ether as internal standard.













TABLE 2







Various aminations of chloro-benzene using ligand 9.













Aryl


Conv.
Yield


Entry
chloride
Amine
Product
[%][a]
[%][a]















1












94
87


 


2[b]












81
57


 


3












100
97


 


4












100
91


 


5












100
94


 


6[c]












100
99


 


7












100
95





5 mmol aryl chloride, 6 mmol amine, 6 mmol NaOtBu, 0.5 mol % Pd(OAc)2, 1 mol % ligand, 5 mL toluene, 20 h, 120° C. Reaction time has not been minimized.


[a]Average of 2 runs, determined by GC using diethyleneglycol di-n-butyl ether or hexadecane as internal standard.


[b]The reaction was conducted within 48 hours.


[c]Ligand 5 was used (2 equiv/Pd).













TABLE 3







Various aminations of functionalized aryl-chlorides


and chloro-pyridines using ligand 9.













Aryl-


Conv.
Yield


Entry
chloride
Amine
Product
[%][a]
[%][a]





 1












100
99


 


 2












100
88


 


 3












100
95


 


 4












100
95


 


 5












100
92


 


 6












100
95


 


 7












100
91


 


 8[b]












100
75


 


 9












100
88


 


10












100
90


 


11












100
97


 


12












100
98


 


13












100
98


 


14












100
60/Lig. 9 99/Lig. 8


 


15[b]












100
92


 


16












100
77/Lig. 9 99/Lig. 8


 


17












100
99/Lig. 8


 


18












100
90


 


19[b]












100
99





5 mmol aryl chloride, 6 mmol amine, 6 mmol NaOtBu, 0.5 mol % Pd(OAc)2, 1 mol % ligand, 5 mL toluene, 20 h, 120° C. Reaction time has not been minimized.


[a]Average of 2 runs, determined by GC using diethyleneglycol di-n-butyl ether or hexadecane as internal standard.


[b]1 mol % Pd(OAc)2, 2 mol % ligand.













TABLE 4







Amination of 3-chloro-toluene with N-methyl-


aniline: variations of temperature and catalyst


loading
















Temp.
Conv.
Yield



Entry
mol % Pd
L/Pd
[° C.]
[%][a]
[%][a]
TON
















1
0.5
2
120
100
95
190


2
0.5
2
100
100
92
184


3
0.5
2
80
100
90
180


4
0.5
2
60
100
89
178


5
0.5
2
40
100
90
180


6
0.25
2
120
100
91
364


7
0.1
2
120
98
86
860


8
0.05
2
120
83
73
1460


9
0.025
2
120
70
62
2480


10
0.025
10
120
78
67
2680


11
0.01
2
120
24
23
2300


12
0.01
25
120
39
33
3300


13
0.01
50
120
45
37
3700





5 mmol aryl chloride, 6 mmol amine, 6 mmol NaOtBu, 5 mL toluene, 20 h. Reaction time has not been minimized.


[a]Average of 2 runs, determined by GC using diethyleneglycol di-n-butyl ether as internal standard.













TABLE 5







Various aminations of aryl-chlorides at low


temperature using ligand 9.













Aryl-


Temp.
Yield


Entry
chloride
Amine
Product
[° C.]
[%][a]





1[b]












25
97


 


2[b]












25
98


 


3












60
91


 


4












60
98


 


5












60
97


 


6












60
91





5 mmol aryl chloride, 6 mmol amine, 6 mmol NaOtBu, 0.5 mol % Pd(OAc)2, 1 mol % ligand, 5 mL toluene, 20 h. Reaction time has not been minimized.


[a]Average of 2 runs, determined by GC using diethyleneglycol di-n-butyl ether or hexadecane as internal standard.


[b]1 mol % Pd(OAc)2, 2 mol % ligand.

## Claims

1. A phosphane ligand of formula (I)



wherein
X independently of Y represents a nitrogen atom or a C-R2 group and
Y independently of X represents a nitrogen atom or a C-R9 group,
R1 for each of the two R1 groups independently of the other represents a radical selected from the group consisting of
a C1-C24-alkyl radical,
a C3-C20-cycloalkyl radical,
which comprises monocyclic, bicyclic, and tricyclic cycloalkyl radicals,

a C5-C14-aryl radical,
which comprises a phenyl radical, a naplithyl radical, and a fluorenyl radical, with the proviso that if one R1 is a non-substituted phenyl, the second R1 cannot be a non-substituted phenyl,

and a C2-C13-heteroaryl radical,

wherein the heteroatoms comprise nitrogen, oxygen, sulfur, or a combination thereof and wherein the number of heteroatoms is from 1 to 2,
wherein the two radicals R1 may be linked to one another,
wherein the above-mentioned radicals R1 may each be mono- or poly-substituted independently of one another by substituents selected from the group consisting of hydrogen, a C1-C20-alkyl radical, a C2-C20-alkenyl radical, a C3-C8-cycloalkyl radical, a C2-C9-hetero-alkyl radical, a C5-C10-aryl radical, a C2-C9-heteroaryl radical,
wherein the heteroatoms comprise nitrogen, oxygen, sulfur, or a combination thereof
and wherein the number of hetero atoms is from 1 to 4,
a C1-C20-alkoxy radical, a C1-C10-haloalkyl radical, a hydroxyl radical, a NH—(C1-C20-alkyl) radical, a NH—(C5-C10-aryl) radical, a N (C1-C20-alkyl)2 radical, a N (C1-C20-alkyl) (C5-C10-aryl) radical, a N(C5-C10-aryl)2 radical, a N(C1-C20-alkyl/C5-C10-aryl3)3+ radical, a NH—CO—C1-C20-alkyl radical, a NH—CO—C5-C10-aryl radical, a COOH radical, a COOQ′ radical, a C1-C6-acyloxy radical, a sulfinato radical, a —SO3H radical, a SO3Q′′ radical and a tri-C1-C6-alkylsilyl radical,
wherein Q′ represents either a monovalent cation or a C1-C8-alkyl radical and Q′′ represents either a monovalent cation, a C1-C20-alkyl radical, or a C5-C10-aryl radical,
wherein two of the mentioned substituents may be bridged with one another,
R2-R9 independently represent hydrogen, an alkyl radical, an alkenyl radical, a cycloalkyl radical, an aromatic or heteroaromatic aryl radical, an O-alkyl radical, an NH-alkyl radical, an N-(alkyl)2 radical, an O-(aryl) radical, an NH-(aryl) radical, an N-(alkyl)(aryl) radical, an O—CO-alkyl radical, a O—CO-aryl radical, a F, a Si(alkyl)3 radical, a CF3 radical, a CN radical, a CO2H radical, a COH radical, an SO3H radical, a CONH2 radical, an CONH(alkyl) radical, a CON(alkyl)2 radical, an SO2(alkyl) radical, a SO(alkyl) radical, a SO(aryl) radical, a SO2(aryl) radical, a SO3(alkyl) radical, a SO3(aryl) radical, an S-alkyl radical, an S-aryl radical, a NH—CO(alkyl) radical, a C2(alkyl) radical, a CONH2 radical, a CO(alkyl) radical, a NHCOH radical, a NHCO2(alkyl) radical, a CO(aryl) radical, or a C2(aryl) radical,
wherein two or more adjacent radicals, each independently of the other(s), may also be linked to one another so that a condensed ring system is present and
wherein in R2 to R9 
an alkyl radical comprises a hydrocarbon radical comprising from 1 to 20 carbon atoms which may be linear or branched, an alkenyl radical represents a mono- or poly-unsaturated hydrocarbon radical comprising from 2 to 20 carbon atoms which may in be linear or branched, a cycloalkyl radical comprises a hydrocarbon comprising from 3 to 20 carbon atoms, an aryl radical comprises a 5- to 14-membered aromatic radical, wherein from one to four carbon atoms in the aryl radical may be replaced by hetero atoms wherein the heteroatoms are nitrogen, sulfur, and oxygen so that a 5- to 14-membered heteroaromatic radical is present, wherein the radicals R2 to R9 may also carry further substituents as defined for R1.

2. The phosphane ligand according to claim 1, wherein X is a CR2 group and Y is a CR9 group.

3. The phosphane ligand of claim 1, wherein X is nitrogen and Y is a CR9 group.

4. The phosphane ligand of claim 1, which comprises at least one radical R1 selected from the group consisting of a phenyl radical, a C1-C10-alkyl radical, a cyclopentyl radical, a cyclohexyl radical, a cyclo-heptyl radical, a 1-adamantyl radical, a 2-adamantyl radical, a 5H-dibenzo-phospholyl radical, a 9-phosphabicyclo[3.3.1]nonanyl radical, and a 9-phospha-bicyclo[4.2.1]nonanyl radicals,
wherein if one R1 is a non-substituted phenyl, the second R1 cannot be a non-substituted phenyl.

5. The phosphane ligand of claim 1, wherein the ligand radicals R2 to R9 are selected from the group consisting of hydrogen, a C1-C10-alkyl radical, a C2-C10 alkenyl radical, a C1-C10-haloalkyl radical, a C3-C8-cycloalkyl radical, a C6-C10-aryl radical, and a C2-C6-heteroaryl radical, wherein from 1 to 3 nitrogen atoms an oxygen atom, a sulfur atom, or a combination thereof may be present and wherein two adjacent radicals R2 to R9 may be bridged with one another.

6. A catalyst comprising at least one metal of sub-group VIII and at least one phosphane ligand of claim 1.

7. The catalyst of claim 6, wherein the catalyst comprises at least one selected from the group consisting of palladium, nickel, platinum, rhodium, iridium, ruthenium a cobalt atom, and a cobalt ion.

8. The catalyst according to claim 6, wherein the catalyst is a mono-, di-, tri- or tetra-phosphane ligand complex of the metal.

9. A catalytic process for converting a chloro or bromo aromatic or vinyl compound to a coupling product comprising:
preparing a reaction mixture comprising a bromo- or chloro aromatic compound or a bromo- or chloro vinyl compound and a second reactant to be coupled to the bromo- or chloro aromatic compound or the bromo- or chloro vinyl compound, and
reacting the bromo- or chloro aromatic compound or the bromo- or chloro vinyl compound with the second reactant to be coupled to the bromo- or chloro aromatic compound or the bromo- or chloro vinyl compound in the presence of the catalyst of claim 6 to form the coupling product
wherein
the catalyst is either fed to the reaction mixture in the form of a complex compound or the catalyst is produced in situ in the reaction mixture.

10. The process of claim 9, wherein the the reaction of the bromo- or chloro aromatic compound or the bromo- or chloro vinyl compound with the second reactant to be coupled to the bromo- or chloro aromatic compound or the bromo- or chloro vinyl compound is at a temperature in a range of from 20 to 200° C.

11. The process of claim 9 wherein a molar ratio of metal to phosphane ligand in the catalyst is from 1:1 to 1:1000.

12. The process according to claim 11, wherein the ratio of metal to ligand is from 1:1 to 1:100.

13. The process of claim 9 wherein a ratio of the metal relative to the bromo- or chloro aromatic compound or the bromo- or chloro vinyl compound is from 5 mol. % to 0.001 mol. %.

14. The ligands of claim 2, wherein the ligands carry at least one radical R1 selected from the group consisting of a phenyl radical, a C1-C10-alkyl radical, a cyclopentyl radical, a cyclohexyl radical, a cyclo-heptyl radical, a 1-adamantyl radical, a 2-adamantyl radical, a 5 H-dibenzo-phospholyl radical, a 9-phosphabicyclo [3.3.1]nonanyl radical, and a 9-phospha-bicyclo[4.2.1]nonanyl radical,
with the proviso that if one R1 is a non-substituted phenyl, the second R1 cannot be a non-substituted phenyl.

15. The ligands of claim 3, wherein the ligands carry at least one radical R1 selected from the group consisting of a phenyl radical, a C1-C10-alkyl radical, a cyclopentyl radical, a cyclohexyl radical, a cyclo-heptyl radical, a 1-adamantyl radical, a 2-adamantyl radical, a 5 H-dibenzo-phospholyl radical, a 9-phosphabicyclo [3.3.1]nonanyl radical, and a 9-phospha-bicyclo[4.2.1]nonanyl radical,
with the proviso that if one R1 is a non-substituted phenyl, the second R1 cannot be a non-substituted phenyl.

16. The ligands of claim 2, wherein the ligand radicals R2 to R9 are selected from the group consisting of hydrogen, a C1-C10-alkyl radical, a C2-C10 alkenyl radical, a C1-C10-haloalkyl radical, a C3-C8-cycloalkyl radical, a C6-C10-aryl radical, and a C2-C6-heteroaryl radical, wherein from 1 to 3 nitrogen atoms an oxygen atom, a sulfur atom, or a combination thereof may be present and wherein two adjacent radicals R2 to R9 may be bridged with one another.

17. The ligands of claim 3, wherein the ligand radicals R2 to R9 are selected from the group consisting of hydrogen, a C1-C10-alkyl radical, a C2-C10 alkenyl radical, a C1-C10-haloalkyl radical, a C3-C8-cycloalkyl radical, a C6-C10-aryl radical, and a C2-C6-heteroaryl radical, wherein from 1 to 3 nitrogen atoms an oxygen atom, a sulfur atom, or a combination thereof may be present and wherein two adjacent radicals R2 to R9 may be bridged with one another.

18. The ligands of claim 4, wherein the ligand radicals R2 to R9 are selected from the group consisting of hydrogen, a C1-C10-alkyl radical, a C2-C10 alkenyl radical, a C1-C10-haloalkyl radical, a C3-C8-cycloalkyl radical, a C6-C10-aryl radical, and a C2-C6-heteroaryl radical, wherein from 1 to 3 nitrogen atoms an oxygen atom, a sulfur atom, or a combination thereof may be present and wherein two adjacent radicals R2 R9 may be bridged with one another.