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Palladium-catalyzed couplings: Literature examples

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1 Palladium-catalyzed couplings: Literature examples
Heck and Sonogashira couplings (alkenes & alkynes) Negishi, Stille, Suzuki-Miyaura, Hiyama (Zn, Sn, B, Si) Martin A. Walker, SUNY Potsdam CC-BY-SA 3.0 license

2 Simple Heck coupling alkene Heck, R. F. Org. React. 1982, 27, 345.

3 An intramolecular Heck coupling
alkene An intramolecular Heck coupling Heck coupling to a trisubstituted alkene is difficult, hence a more active trifluoroacetate catalyst is used. Note also how the double bond “migrates”; this quite often occurs. Hong, C. Y.; Kado, N.; Overman, L. E. J. Am. Chem. Soc. 1993, 115,

4 The Sonogashira coupling
alkyne The Sonogashira coupling Use of the Sonogashira coupling to couple an alkyne with a vinyl iodide. The product (after removal of the TMS group) is (+)-obtusenyne, a metabolite of Laurencia red algae. Crimmins MT, Powell MT. " Enantioselective Total Synthesis of (+)-Obtusenyne", Journal of the American Chemical Society, 2003, 125 (25), 7592– doi: /ja029956v

5 Negishi coupling organozinc dppe is a bidentate phosphine ligand
Herbert, John M. Tetrahedron Lett. 2004, 45(4), 817–819.

6 Stille coupling: organotin
Preparation of an aryl triflate, followed by a Stille coupling. Furstner A, Seidel G, Kindler N. "Macrocydes by Ring-Closing-Metathesis, XI 1: Syntheses of (R)-(+)-Lasiodiplodin, Zeranoi and Truncated Salicylihalamides", Tetrahedron 1999, 55, doi: /S (99)

7 The Suzuki-Miyaura reaction
organoboron The Suzuki-Miyaura reaction The arylboronic acids & esters are often prepared from aryllithiums. Denton TT, Zhang X, Cashman JR. "5-Substituted, 6-Substituted, and Unsubstituted 3-Heteroaromatic Pyridine Analogues of Nicotine as Selective Inhibitors of Cytochrome P-450 2A6", Journal of Medicinal Chemistry, 2005, 48 (1), 224– doi: /jm049696n

8 Suzuki-Miyaura coupling in synthesis
organoboron Suzuki-Miyaura coupling in synthesis A typical use of the Suzuki-Miyaura coupling in synthesis is shown in Mandal's 2002 synthesis of (-)-ebelactone A. Note that here an alkylborane is used, easily prepared by hydroboration. dppf is a bidentate phosphine ligand. Mandal, AK. "Stereocontrolled Total Synthesis of (-)-Ebelactone A", Organic Letters, 2002, 4, doi: /ol020058d

9 Molander variation of the Suzuki-Miyaura coupling
organoboron Molander variation of the Suzuki-Miyaura coupling This uses an alkyltrifluoroborate salt. Molander GA, Petrillo DE. "Suzuki-Miyaura Cross-Coupling of Potassium Trifluoroboratohomoenolates", Organic Letters, 2008, 10, doi: /ol800357c

10 Hiyama coupling organosilane
Pierrat P, Gros P, Fort Y. "Hiyama Cross-Coupling of Chloro-, Fluoro-, and Methoxypyridyltrimethylsilanes: Room-Temperature Novel Access to Functional Bi(het)aryl", Organic Letters, 2005, 7(4), doi: /ol047482u


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