title: Palladium-Catalyzed Defluorinative Coupling of 1-Aryl-2,2-Difluoroalkenes and Boronic Acids: Stereoselective Synthesis of Monofluorostilbenes.
abstract: The palladium-catalyzed defluorinative coupling of 1-aryl-2,2-difluoroalkenes with boronic acids is described. Broad functional-group tolerance arises from a redox-neutral process by a palladium(II) active species which is proposed to undergo a β-fluoride elimination to afford the products. The monofluorostilbene products were formed with excellent diastereoselectivity (≥50:1) in all cases, and it is critical, as traditional chromatographic techniques often fail to separate monofluoroalkene isomers. As a demonstration of this method's unique combination of reactivity and functional-group tolerance, a Gleevec® analogue, using a monofluorostilbene as an amide isostere, was synthesized.
authors: Department of Chemistry, University of California, Berkeley, Berkeley, CA, 94720, USA.
authors: Richard T
authors: RT
authors: Thornbury
authors: Department of Chemistry, University of California, Berkeley, Berkeley, CA, 94720, USA. fdtoste@berkeley.edu.
authors: F Dean
authors: FD
authors: Toste
mesh_terms: D000475:Alkenes / Q000737:chemistry*; D001897:Boronic Acids / Q000737:chemistry*; D002384:Catalysis; D005461:Fluorine / Q000737:chemistry; D000068877:Imatinib Mesylate / Q000031:analogs & derivatives / Q000138:chemical synthesis; D010165:Palladium / Q000737:chemistry*; D013237:Stereoisomerism; D013267:Stilbenes / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D000475:Alkenes; D001897:Boronic Acids; D013267:Stilbenes; D005461:Fluorine; D010165:Palladium; D000068877:Imatinib Mesylate
keywords: C−C coupling; alkenes; fluorine; palladium; synthetic methods