Methods and systems for preparing fused heterocyclic compounds using copper(I) catalysts
A copper(I)-catalyzed procedure for the synthesis of benzo[b]heterocycles. This protocol can be used to synthesize a variety of 2-arylbenzo[b]furans and indoles in good to excellent yields. This method can tolerate a variety of functional groups, does not require the use of expensive additives and is palladium-free.
1. A method of using a Cu(I) compound for benzo[b]heterocycle preparation, said method comprising:
providing an aryl acetylene, and one of an o-halophenol and an o-haloaniline; and
contacting said acetylene and one of said aniline and said phenol with a Cu(I) bi-dentate ligand compound, said method absent a palladium catalyst.
2. The method of claim 1 wherein said bi-dentate ligand is selected from 1,10-phenanthroline and 2,9-dimethyl-1,10-phenanthroline.
3. The method of claim 2 wherein said Cu(I) compound comprises the reaction product of a Cu(I) halide and one of said bi-dentate ligands.
4. The method of claim 1 further comprising a base component.
5. The method of claim 1 wherein said o-haloaniline is selected from o-iodoaniline, and said o-halophenol is selected from o-iodophenols.
6. A method for preparing benzo[b]heterocycles from acetylenes, said method comprising:
providing an aryl acetylene, and one of an o-halophenol and an o-haloaniline;
contacting said acetylene and one of said aniline and said phenol with a medium comprising a Cu(I) bi-dentate ligand compound said medium absent a palladium catalyst and comprising a solvent component.
7. The method of claim 6 wherein said bi-dentate ligand is selected from 1,10-phenanthroline and 2,9-dimethyl-1,10-phenanthroline.
8. The method of claim 7 wherein said Cu(I) compound is selected from Cu(phen)(PPh 3 ) 2 NO 3 and Cu(neocuproine)(PPh 3 )Br.
9. The method of claim 8 wherein said solvent is selected from toluene and isopropyl alcohol.
10. The method of claim 8 wherein said medium further comprises a base component.
11. A method of using a Cu(I) compound for benzofuran synthesis, said method comprising:
providing an aryl acetylene;
providing an o-halophenol; and
contacting said acetylene and phenol compounds with a medium comprising a Cu(I) bi-dentate ligand compound, said method absent a palladium catalyst.
12. The method of claim 11 comprising a catalytic amount of said Cu(I) compound.
13. The method of claim 11 wherein said bi-dentate ligand is selected from 1,10-phenanthroline and 2,9-dimethyl-1,10-phenanthroline.
14. The method of claim 11 further comprising a base component.
15. A method of using a Cu(I) compound for indole synthesis, said method comprising:
providing an aniline compound comprising one of a halide substituent and an acetylenic substituent at a position ortho to the N-moiety of said aniline compound;
providing an aryl compound, said aryl compound comprising an acetylenic substituent where said ortho substituent is halide and a halide substituent where said ortho substituent is acetylenic; and
contacting said compounds with a Cu(I) bi-dentate ligand compound said method absent a palladium catalyst.
16. The method of claim 15 comprising a catalytic amount of said Cu(I) compound.
17. The method of claim 15 wherein said bi-dentate ligand is selected from 1,10-phenanthroline and 2,9-dimethyl-1,10-phenanthroline.
18. The method of claim 15 further comprising a base component.