Cost effective method of producing triarylamine compounds having two alkly alcohols
The present invention provides a simple, cost effective and time saving one step method for synthesizing triarylamines comprising two alkyl alcohol without the need for the protection and the deprotection steps. More particularly, the invention provides an improved method of producing triarylamine compounds having two alkyl alcohol groups by reaction of a primary arylamine (aniline) with a halogenated aryl alkyl alcohol. The reaction proceeds in one step, whereby a primary arylamine is reacted with two equivalents of a halogenated aryl alkyl alcohol in the presence of a catalytic amount of palladium, ligand, solvent and base.
1. A method for forming triarylamine compounds comprising two alkyl alcohol groups comprising the steps of reacting a halogenated aryl alkyl alcohol with a primary aryl amine in the presence of a base having an alkaline metal salt of a bis(trialkylsilyl)amide, represented by the general formula MN(SiR 3 ) 2 ,
wherein:
M is an lithium ion,
N is a nitrogen atom; and
R is an methyl group,
solvent, palladium precursor and ligand(s).
2. The method of claim 1 , where in the halogenated aryl alkyl alcohol is represented as follows:
X—Ar((C n H 2n )—OH) 2
wherein:
X is a halogen,
Ar is an aryl group; and
C n H 2n is an alkyl group.
3. The method of claim 2 , wherein Ar is a phenyl group.
4. The method of claim 2 , wherein X is selected from the group consisting of chlorine, bromine and iodine.
5. The method of claim 4 , wherein X is chlorine.
6. The method of claim 4 , wherein X is bromine.
7. The method of claim 2 wherein C n H 2n is a lower alkyl group having between 1 and 12 carbon atoms.
8. The method of claim 2 , wherein is (C n H 2n )—OH is a primary alkyl alcohol.
9. The method of claim 1 , wherein the palladium precursor is selected from the group consisting of tris(dibenzylideneacetone)dipalladium (Pd 2 (dba) 3 ) and palladium acetate.
10. The method of claim 9 , wherein the palladium precursor is tris(dibenzylideneacetone)dipalladium (Pd 2 (dba) 3 ).
11. The method of claim 1 , wherein the ligand is selected from the group consisting of 2-Di-tert-butylphosphino-2′,4′,6′-triisopropylbiphenyl (tBuXPhos), 1,1′-Ferrocenediyl-bis(diphenylphosphine) (DPPF) and tri tert-butylphosphine.
12. The method of claim 11 , wherein the ligand is 2-Di-tert-butylphosphino-2′,4′,6′-triisopropylbiphenyl (tBuXPhos).
13. The method of claim 1 , wherein the ligand is a mixture of 2-Dicyclohexylphosphino-2′,6′-diisopropoxybiphenyl (RuPhos) and 2-(Dicyclohexylphosphino)3,6-dimethoxy-2′,4′,6′-triisopropyl-1,1′-biphenyl (BrettPhos).
14. The method of claim 1 , wherein the solvent is selected from the group consisting of: cyclic ethers such as tetrahydrofuran (THF), ethers such as diethyl ether or tert-butyl methyl ether, aromatic solvents such as toluene or xylene, acetate solvents such as ethyl acetate or butyl acetate, aliphatic solvents such as hexane or decane, and amide solvents such as dimethyl formamide (DMF), dimethyl acetamide (DMAc) and N-methylpyrrolidone (NMP).
15. The method of claim 14 , wherein the solvent is tetrahydrofuran THF.
16. The method of claim 13 wherein the ratio of the of 2-Dicyclohexylphosphino-2′,6′-diisopropoxybiphenyl (RuPhos) to 2-(Dicyclohexylphosphino)3,6-dimethoxy-2′,4′,6′-triisopropyl-1,1′-biphenyl (BrettPhos) is about 1:4.