Pd-catalyzed carbonylation of aryl tosylates and sulfonates

ORGN 271

Chaoxian Cai, chaoxian_cai@merck.com1, Nelo Rivera1, Jaume Balsells-Padros1, J. Chris McWilliams1, Rick Sidler1, Yongkui Sun2, and David J. Mathre3. (1) Process Research, Merck Research Laboratories, P.O.Box 2000, Rahway, NJ 07065, (2) Department of Process Research, Merck & Co, Rahway, NJ 07065, (3) Center for Physichochemical Characterization, Merck Research Laboratories, Process Research, P. O. Box 2000, Rahway, NJ 07065
Ethyl arylcarboxylates were synthesized by palladium-catalyzed carbonylation of various p-flurophenylsulfonates or tosylates. A unique Joshiphos type ligand was discovered through high throughput screening approach, which was the key for the successful carbonylation of various substrates. The catalyst is very effective and works for substrates with either electron withdrawing, neutral or donating functional groups. Isolated yields of greater than 90% were obtained for various types of p-flurophenylsulfonates in the reaction scope studies. The use of base and solvent is also crucial in order to obtain high conversions of starting materials. The additive effect will also be discussed. The addition of zirconium chloride can significantly facilitate the carbonylation process.

 

Metal-Mediated Reactions and Syntheses
8:00 AM-12:00 PM, Monday, 11 September 2006 Moscone Center -- Room 133, Oral

Division of Organic Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006