Olefin metathesis catalysts and related methods
The present invention provides methods for the synthesis of catalysts and precursors thereof. Methods of the invention may comprise combining a catalyst precursor and at least one ligand to generate a catalytically active species, often under mild conditions and in high yields. In some cases, a wide variety of catalysts may be synthesized from a single catalyst precursor. Methods of the invention may also include the preparation of catalysts which, under reaction conditions known in the art, may have been difficult or impossible to prepare and/or isolate due to, for example, steric crowding at the metal center. The present invention also provides catalyst compositions, and precursors thereof, which may be useful in various chemical reactions including olefin metathesis. In some cases, methods of the invention may reduce the number of synthetic and purification steps required to produce catalysts and/or other reaction products, as well as reducing time, cost, and waste production.
1. A compound of formula:
wherein:
M is Mo or W;
R 1 is an optionally substituted alkyl group;
R 2 and R 3 can be the same or different and are hydrogen, or an optionally substituted group selected from alkyl, heteroalkyl, aryl, or heteroaryl; and
R 6 and R 7 can be the same or different and are an optionally substituted group selected from heteroalkyl or heteroaryl, or R 6 and R 7 are joined together to form an optionally substituted bidentate ligand with respect to M; and wherein at least one of R 6 and R 7 is an oxygen-containing ligand, wherein said compound is other than
2. The compound according to claim 1 , wherein each of R 6 and R 7 is an oxygen-containing ligand.
3. The compound according to claim 1 , wherein the oxygen-containing ligand coordinates M via an oxygen atom.
4. The compound according to claim 3 , wherein R 6 and R 7 are joined together to form a biphenolate or binaphtholate ligand.
5. The compound according to claim 1 , wherein R 1 is optionally substituted adamantyl.
6. The compound according to claim 3 , wherein one of R 2 and R 3 is hydrogen and the other of R 2 and R 3 is an optionally substituted group selected from alkyl, heteroalkyl, aryl, or heteroaryl.
7. The compound according to claim 3 , wherein:
M is Mo;
R 2 is optionally substituted alkyl; and
R 3 is hydrogen.
8. The compound according to claim 3 , wherein:
M is W;
R 2 is optionally substituted alkyl; and
R 3 is hydrogen.
9. The compound according to claim 3 , wherein the oxygen-containing ligand is chiral.
10. The compound according to claim 3 , wherein R 6 and R 7 are taken together to form an optionally substituted bidentate ligand with M wherein the bidentate ligand is chiral.
11. A compound selected from:
or Mo(N-2,6-Br 2 -4-MeC 6 H 2 )(CHCMe 3 )[rac-Biphen], wherein Biphen is 3,3′-di-t-butyl-5,5′,6,6′-tetramethyl-1,1′-biphenyl-2,2′-diolate.
12. The compound according to claim 1 , wherein M is Mo.
13. The compound according to claim 1 , wherein M is W.