Catalyst
A process for the preparation of a compound of formula (V): comprising at least the step of reacting a compound of formula (VI) with a compound (VII) wherein; R 2 is hydrogen or a C1-C20 hydrocarbyl radical provided that at least one R 2 is not hydrogen; R 5 is hydrogen or a C1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16; R 6 is hydrogen or a C1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16; n is 1, 2 or 3; each R 8 is a C1-20 hydrocarbyl group; and Hal is a halide; in the presence of a nickel imidazolidin-2-ylidene compound.
1. A process for the preparation of a compound of formula (V):
comprising at least the step of reacting a compound of formula (VI)
with a compound (VII)
wherein;
R 2 is hydrogen or a C1-C20 hydrocarbyl radical provided that at least one R 2 is not hydrogen;
R 5 is hydrogen or a C1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16;
R 6 is hydrogen or a C1-20 hydrocarbyl group optionally containing one or more heteroatoms from groups 14-16;
n is 1, 2 or 3;
each R 8 is a C1-20 hydrocarbyl group; and
Hal is a halide;
in the presence of a nickel imidazolidin-2-ylidene compound.
2. A process as claimed in claim 1 wherein said compound of formula (V) is
3. A process as claimed in claim 1 , wherein said nickel imidazolidin-2-ylidene compound is PPh 3 IPrNiCl 2 , wherein IPr represents 1,3-bis(2,6-diisopropylphenyl)imidazolidin-2-ylidene or 1,3-bis(2,4,6-trimethylphenyl)imidazolidin-2-ylidene.
4. A process as claimed in claim 1 , further comprising a step of contacting the reaction product of compounds (VI) and (VII) with an acid catalyst.
5. A process as claimed in claim 4 , wherein said acid catalyst is tosyl alcohol.
6. A process as claimed in claim 1 , wherein the alkoxy group at the 1-position in formula (VI) is MeO—.
7. A process as claimed in claim 1 , wherein
R 2 is hydrogen or a C1-C20 hydrocarbyl radical provided that at least one R 2 is not hydrogen;
R 5 is hydrogen or an aliphatic C1-20 hydrocarbyl group;
R 6 is hydrogen or an aliphatic C1-20 hydrocarbyl group;
n is 1, 2 or 3; and
each R 8 is an aliphatic C1-20 hydrocarbyl group.
8. A process as claimed in claim 1 , wherein
R 2 is a C1-10 alkyl group;
R 5 is hydrogen or a C1-10 alkyl group;
R 6 is hydrogen or a C1-10 alkyl group;
n is 1 to 3;
and each R 8 is a C1-20 hydrocarbyl group.
9. A process as claimed in claim 1 , wherein
R 2 is a C1-10 alkyl group;
n is 1 to 3;
R 5 is hydrogen;
R 6 is hydrogen;
and each R 8 is a C1-10 alkyl group or C6-10 aryl group.
10. A process as claimed in claim 1 , wherein
R 5 is hydrogen;
R 6 is hydrogen;
R 2 is methyl;
n is 2; and
R 8 is C3-8 alkyl and R 8 is in the 3,5-position on the ring.
11. A process as claimed in claim 1 , wherein the halide is Br.