Method for manufacturing ruthenium carbene complexes
View Patent ↗A method of manufacturing ruthenium carbene complexes and novel aryl alkylidene ruthenium complexes based on the method, the complexes able to used as catalysts in metathesis reactions.
1. A process for preparing ruthenium complexes of the general formula (I)
RuX 2 (═CH—CH 2 R)L 2 (I),
wherein
X is an anionic ligand,
R is hydrogen or a (C 1 -C 18 )-alkyl, (C 3 -C 8 )-cycloalkyl, (C 2 -C 7 )-heterocycloalkyl, (C 6 -C 14 )-aryl or (C 3 -C 14 )-heteroaryl radical and
L is selected from the group consisting of phosphanes, phosphinites, phosphonites and phosphites,
which comprises
A) reacting an Ru metal salt of the general formula (II):
RuX x N y (II),
wherein
x is an integer greater than or equal to 2 and
X is as defined above,
y is an integer greater than or equal to 0
and y>=1;
the ligands N are identical or different coordinating uncharged ligands;
with L in the presence of a base and a reducing agent and
B) subsequently reacting with a silylalkyne of the general formula III
R—C≡CSiR′ 3 (III),
wherein
R is as defined above,
the radicals R′ are identical or different radicals which can be selected from the group consisting of hydrogen, (C 1 -C 8 )-alkyl, (C 1 -C 8 )-alkoxy, (C 6 -C 10 )-aryloxy, (C 6 -C 10 )-aryl.
2. A process for preparing ruthenium complexes of the general formula
RuX 2 (═R 1 R 2 )L 2 ,
where
X is an anionic ligand,
L is selected from the group consisting of phosphanes, phosphinites, phosphonites and phosphites,
R 1 is hydrogen or a (C 1 -C 18 )-alkyl or (C 3 -C 8 )-cycloalkyl or (C 2 -C 7 )-heterocycloalkyl, (C 6 -C 14 )-aryl or (C 3 -C 14 )-heteroaryl radical and R 2 is a (C 6 -C 14 )-aryl or (C 3 -C 14 )-heteroaryl radical and the radicals R 1 and R 2 can have a 5-7-membered ring, which comprises
A) reacting an Ru metal salt of the general formula (II):
RuX x N y (II),
wherein
x is an integer greater than or equal to 2 and
X is as defined above,
y is an integer greater than or equal to 0
and y>=1;
the ligands N are identical or different coordinating uncharged ligands;
with L in the presence of a base and a reducing agent and
B) subsequently reacting with a silylalkyne of the general formula III
R—C≡CSiR′ 3 (III),
wherein
R and R′ have the meanings given in claim 1 , and
C) subsequently reacting with an alkene of the general formula IV
H 2 C═CR′R 2 (IV),
wherein
R 1 and R 2 have the meanings given above.
3. The process according to claim 1 , wherein L is selected from the group consisting of triphenylphosphane, triisopropylphosphane, tricyclohexylphosphane and 9-cyclohexyl-9-phosphabicyclo[3.3.1]nonane.
4. The process according to claim 1 , wherein x=3 and y=0 for the Ru metal salt of the general formula RuX x N y and that the reduction of the Ru metal salt is carried out by means of hydrogen in the presence of metallic reducing agent.
5. The process according to claim 3 , wherein said reducing agent is magnesium.
6. The process according to claim 1 , wherein an excess of basic ligand is used as base.
7. The process according to claim 1 , wherein x>=2 and y>0 for the Ru metal salt of general formula RuX x N y and that the reduction of the Ru metal salt is carried out by means of alcohol or the formic acid-triethylamine complex.
8. The process according to claim 7 , wherein said reducing agent is a secondary alcohol.
9. The process according to claim 1 , wherein said base is an amine.
10. The process according to claim 9 , wherein said base is triethylamine or 1,8-diazobicyclo[5.4.0]undec-7-ene.
11. The process according to claim 2 , wherein L is selected from the group consisting of triphenylphosphane, triisopropylphosphane, tricyclohexylphosphane and 9-cyclohexyl-9-phosphabicyclo[3.3.1]nonane.