New ammonia equivalents for the Pd-catalyzed amination of aryl halides

Organic Letters

Volumn 3, Issue 21, 2001, Pages 3417-3419

  Huang, Xiaohua ^a   Buchwald, Stephen L ^a  

^a MASSACHUSETTS INSTITUTE OF TECHNOLOGY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

AMINE; AMMONIA; ANILINE DERIVATIVE; BENZENE DERIVATIVE; HALOGEN; PALLADIUM;

AMINATION; ARTICLE; CATALYSIS; CHEMISTRY; COMBINATORIAL CHEMISTRY; SYNTHESIS;

AMINATION; AMINES; AMMONIA; ANILINE COMPOUNDS; BENZENE DERIVATIVES; CATALYSIS; COMBINATORIAL CHEMISTRY TECHNIQUES; HALOGENS; PALLADIUM;

EID: 0035909622     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol0166808     Document Type: Article

References (18)

1. (a) Hartwig, J. F. Angew. Chem., Int. Ed. Engl. 1998, 37, 2046-2067.
2. (b) Hartwig, J. F.; Kawatsura, M.; Hauck, S. I.; Shaughnessy, K. H.; Alcazar-Roman, L. M. J. Org. Chem. 1999, 64, 5575-5580.
3. (c) Yang, B. H.; Buchwald, S. L. J. Organomet. Chem. 1999, 576, 125-146.
4. (d) Wolfe, J. P.; Buchwald, S. L. J. Org. Chem. 2000, 65, 1144-1157.
5. (e) Wolfe, J. P.; Tomori, H.; Sadighi, J. P.; Yin, J.; Buchwald, S. L. J. Org. Chem. 2000, 65, 1158-1174 and references therein.
6. Ammonia has been used in the Cu-catalyzed animation of 2-bromopyridines: Lang, F.; Zewge, D.; Houpis, I. N.; Volante, R. P. Tetrahedron Lett. 2001, 42, 3251-3254.
7. (a) Wolfe, J. P.; Åhman, J.; Sadighi, J. P.; Singer, R. A.; Buchwald, S. L. Tetrahedron Lett. 1997, 38, 6367-6370. See also:
8. (b) Mann, G.; Hartwig, J. F.; Driver, M. S.; Fernandez-Rivas, C. J. Am. Chem. Soc. 1998, 120, 827-828.
9. For other ammonia equivalents in Pd-catalyzed aminations, see: (a) Hori, K.; Mori, M. J. Am. Chem. Soc. 1998, 120, 7651-7652.
10. (b) Jaime-Figueroa, S.; Liu, Y.; Muchowski, J. M.; Putman, D. G. Tetrahedron Lett. 1998, 39, 1313-1316.
11. (c) Lim, C. W.; Lee, S. Tetrahedron 2000, 56, 5131-5136.
12. (d) Bolm, C.; Hildebrand, J. P. Tetrahedron Lett. 1998, 39, 5731-5734
13. In situ generated CuHMDS has been used in the stoichiometric amination of aryl iodides: King, F. D.; Walton, R. M. J. Chem. Soc., Chem. Commun. 1974, 256-257.
14. Lee, S.; Jørgensen, M.; Hartwig, J. F. Org. Lett. 2001, 3, 2729-2732.
15. 4, filtered, and concentrated in vacuo. The product was purified by flash chromatography.
16. 3 (4.6 mg, 5.0 μmol, 0.50 mol %), 2-dicyclohexylphosphinobiphenyl (1) (4.2 mg, 12 μmol, 1.2 mol %), and 1,1,1-triphenylsilylamine (330 mg, 1.2 mmol). The Schlenk tube was evacuated and back-filled with argon, and aryl halide (1.0 mmol) was added via syringe. The Schlenk tube was sealed with a Teflon screw cap and brought into a glovebox. Lithium bis(trimethylsilyl)amide (220 mg, 1.3 mmol) and toluene (1 mL) were added in the glovebox. The Schlenk tube was then sealed with a Teflon screw cap, brought out of the glovebox and placed in a 100°C oil bath for 16-20 h. After the reaction mixture was cooled to room temperature, the workup described in General Procedure A was performed and the product was purified by flash chromatography.
17. For a Pd-based route to unsymmetrical triarylamines, see: Harris, M. C.; Buchwald, S. L. J. Org. Chem. 2000, 65, 5327-5333.
18. 3 (9.2 mg, 10 μmol, 1.0 mol %) and 2-(di-tert-butylphosphino)biphenyl (2) (7.2 mg, 24 μmol, 2.4 mol %). The Schlenk tube was evacuated and back-filled with argon, and aryl halide was added via syringe. The Schlenk tube was sealed with a Teflon screw cap and brought into a glovebox. Lithium amide (23 mg, 1.0 mmol), sodium tert-butoxide, and solvent (1 mL) were added in the glovebox. The Schlenk tube was then sealed with a Teflon screw cap, brought out of the glovebox, and placed in a preheated oil bath for 19 h. The reaction mixture was cooled to room temperature, diluted with ether, passed through a pad of Celite, and concentrated in vacuo. The residue was purified by flash chromatography.