Methods for preparing bridged bi-aromatic ligands
New methods for preparing bridged bi-aromatic ligands are disclosed. The methods employ aryl coupling of unprotected phenols. The ligands may be used to prepare transition metal compounds useful as catalysts in olefin polymerization.
1. A method for preparing a bridged bi-aromatic phenol ligand of formula (I) from a compound containing at least one phenol group wherein the at least one phenol group remains unprotected during all steps of the method and the method comprises at least one step of aryl coupling;
wherein each of R 1 , R 2 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 and R 14 is independently selected from the group consisting of hydrogen, halide, optionally substituted hydrocarbyl, heteroatom-containing optionally substituted hydrocarbyl, alkoxy, aryloxy, silyl, boryl, dialkyl amino, alkylthio, arylthio and seleno; optionally two or more R groups combine together into ring structures with such ring structures having from 3 to 100 non-hydrogen atoms in the ring; A is a bridging group having from one to 50 non-hydrogen atoms; Y and Y′ are independently selected from O, S, NR a and PR a wherein R a is optionally substituted hydrocarbyl; Ar is optionally substituted aryl or optionally substituted heteroaryl.
2. The method according to claim 1 comprising the step of:
treating an unprotected phenol of formula (II) with a compound of formula (III)
in the presence of a catalyst so as to form the compound of formula (I); wherein each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 and R 14 is independently selected from the group consisting of hydrogen, halide, optionally substituted hydrocarbyl, heteroatom-containing optionally substituted hydrocarbyl, alkoxy, aryloxy, silyl, boryl, dialkyl amino, alkylthio, arylthio and seleno; optionally two or more R groups combine together into ring structures with such ring structures having from 3 to 100 non-hydrogen atoms in the ring; A is a bridging group having from one to 50 non-hydrogen atoms; Y and Y′ are independently selected from O, S, NR a and PR a wherein R a is optionally substituted hydrocarbyl; X is halide; Ar is optionally substituted aryl or optionally substituted heteroaryl; Z and Z′ are independently selected from BR b 2 and BF 3 − M + , wherein R b is independently selected from hydrogen, alkyl, hydroxy and alkoxy, wherein when both of R b are alkoxy, optionally they combine to form a ring structure of formula BO 2 R b 2 , and wherein M + is an alkali metal cation.
3. The method according to claim 2 further comprising the steps of
a) treating a compound of formula (IV) with a compound of formula (V);
in the presence of a catalyst so as to yield a compound of formula (VI); and
b) treating the compound of formula (VI) with a source of halogen so as to yield the compound of formula (II);
wherein X is halide; R 1 , R 2 , R 3 , Ar, BR b 2 and M + are as defined in claim 2 .
4. The method according to claim 2 further comprising the steps of:
a) halogenating a compound of formula (VII) to yield a compound of formula (VIII); and
b) treating the compound of formula (VIII) with a compound of formula (V) in the presence of a catalyst to yield the compound of formula (II);
wherein X, R 1 , R 2 and R 3 are as defined in claim 2 .
5. The method according to claim 1 wherein the catalyst comprises a nickel or palladium catalyst.
6. The method according to claim 5 wherein the palladium catalyst comprises a palladium phosphine catalyst.
7. The method according to claim 5 wherein the palladium catalyst comprises bis(tri-tert-butylphosphine)palladium, tetrakis(triphenylphosphine)palladium(0) (Pd(PPh 3 ) 4 ), bis[1,2-bis(diphenylphosphino)ethane]palladium(0) (Pd(dppe) 2 ), 1,1′-bis(diphenylphosphino)ferrocene palladium (Pd(dppf)), or (2,2′-bis(diphenylphosphino)-1,1′-binaphthyl palladium (Pd(BINAP).
8. The method according to claim 2 wherein the catalyst further comprises a base.
9. The method according to claim 8 wherein the base comprises an alkali metal carbonate, alkali metal phosphate, alkali metal hydroxide, alkali metal alkoxide or an amine.
10. The method according to claim 2 wherein X is bromo or chloro.
11. The method according to claim 1 comprising the steps of:
a) treating a compound of formula (IV) with a compound of formula (V) in the presence of a catalyst so as to yield a compound of formula (VI);
b) treating the compound of formula (VI) with a source of halogen so as to yield the compound of formula (II); and
c) treating the unprotected phenol of formula (II) with a compound of formula (III) to yield the compound of formula (I);
wherein each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 and R 14 is independently selected from the group consisting of hydrogen, halide, optionally substituted hydrocarbyl, heteroatom-containing optionally substituted hydrocarbyl, alkoxy, aryloxy, silyl, boryl, dialkyl amino, alkylthio, arylthio and seleno; optionally two or more R groups combine together into ring structures with such ring structures having from 3 to 100 non-hydrogen atoms in the ring; A is a bridging group having from one to 50 non-hydrogen atoms; Y and Y′ are independently selected from O, S, NR a and PR a wherein R a is optionally substituted hydrocarbyl; X is halide; Ar is optionally substituted aryl or optionally substituted heteroaryl; Z and Z′ are independently selected from BR b 2 and BF 3 − M + , wherein R b is independently selected from hydrogen, alkyl, hydroxy and alkoxy, wherein when both of R b are alkoxy, optionally they combine to form a ring structure of formula BO 2 R b 2 , and wherein M + is an alkali metal cation.
12. The method according to claim 1 wherein each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 and R 14 is independently selected from the group consisting of hydrogen, halide, optionally substituted alkyl, heteroalkyl, aryl, heteroaryl, alkoxyl, aryloxyl, silyl, boryl, dialkylamino, alkylthio, arylthio, and seleno.
13. The method according to claim 1 wherein each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 and R 14 is independently selected from the group consisting of hydrogen, halide, optionally substituted alkyl, heteroalkyl, aryl, heteroaryl, alkoxyl, aryloxyl, silyl, dialkylamino, alkylthio, and arylthio.
14. The method according to claim 1 wherein each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 and R 14 is independently selected from the group consisting of hydrogen, and optionally substituted alkyl and aryl.
15. The method according to claim 1 wherein the bridging group A is selected from the group consisting of optionally substituted divalent hydrocarbyl and divalent heteroatom containing hydrocarbyl.
16. The method according to claim 1 wherein the bridging group A is selected from the group consisting of optionally substituted divalent alkyl, alkenyl, alkynyl, heteroalkyl, heteroalkenyl, heteroalkynyl, carbocycle, heterocarbocycle, aryl, heteroaryl and silyl.
17. The method according to claim 1 wherein the bridging group A is an optionally substituted divalent alkyl.
18. A method according to claim 1 wherein the bridging group A is represented by the general formula -(QR 15 2-z″ ) z′ — wherein each Q is either carbon or silicon and each R 15 is the same or different from the others such that each R 15 is selected from the group consisting of hydrogen and optionally substituted hydrocarbyl and heteroatom containing hydrocarbyl, and optionally two or more R 15 groups join into a ring structure having from 3 to 50 atoms in the ring structure not counting hydrogen atoms; z′ is an integer from 1 to 10; and z″ is 0, 1 or 2.
19. The method according to claim 1 wherein Ar is selected from optionally substituted phenyl, naphthyl, biphenyl, anthracenyl, and phenanthrenyl.
20. The method according to claim 1 wherein Ar is selected from thiophene, pyridine, isoxazole, pyrazole, pyrrole, furan or benzo-fused analogues of these rings.