iron catalyzed cross-coupling reaction: recent advances and primary mechanism

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Iron Catalyzed Cross-Coupling Reaction: Recent Advances and Primary Mechanism. Wang Chao 2010.11.6. General:. Cheap Enviromentally benign Sustainable Unique reactivity. Genesis:. Kharasch: J. Am. Chem. Soc. 1941 , 63 , 2316. Kochi: J. Am. Chem. Soc. 1971 , 93 , 1487. - PowerPoint PPT Presentation

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  • Iron Catalyzed Cross-Coupling Reaction:Recent Advances and Primary MechanismWang Chao2010.11.6

  • General:CheapEnviromentally benignSustainableUnique reactivity

  • Genesis:Kochi: J. Am. Chem. Soc. 1971, 93, 1487Kharasch: J. Am. Chem. Soc. 1941, 63, 2316

  • Acid chlorides as electrophiles

  • Alkenyl electrophiles(-)-cubebene (5)

  • Furstner: Angew. Chem., Int. Ed. 2002, 41, 609Aryl electrophiles:

  • allyl, vinyl, and aryl Grignard reagents uniformly led to poor yields in reactions performed with FeX3 (X =Cl, acac) in THF/NMP

  • a valuable component of liquid-crystalline materialsspermidine alkaloid

  • Masaharu Nakamura: J. AM. CHEM. SOC. 2007, 129, 9844-9845

  • Alkyl halidesNakamura, Eiichi: J. AM. CHEM. SOC. 2004, 126, 3686-3687the high barrier to oxidative addition b-hydride elimination

  • Hayashi: Org. Lett. 2004, 6, 12971299.

  • Angew. Chem. Int. Ed. 2004, 43, 3955 3957L = TMEDA

  • [FeCl (salen)]Cahiez: Angew. Chem. Int. Ed. 2007, 46, 4364 4366Bedford: Chem. Commun.2004, 28222823.

  • Bedford: J. Org. Chem. 2006, 71, 1104-1110Iron-Phosphine, -Phosphite, -Arsine, and -Carbene Catalysts

  • Kochi, J. J. Org. Chem. 1976, 41, 502

    Mechanism for the cross coupling:

  • Bogdanovic:four-electron reduction, formal constitution [Fe(MgCl)2]n1:1 mixture of alkene and alkane is formed from the Grignard reagent in the reduction of FeX2, Bogdanovic proposed a -hydride elimination followed by a reductive elimination as two of the elementary steps

  • 1:1 mixture of alkene and alkane is formed from the Grignard reagent in the reduction of FeX2, Bogdanovic proposed a -hydride elimination followed by a reductive elimination as two of the elementary steps in the formation of [Fe(MgX)2]

  • J. AM. CHEM. SOC. 2008, 130, 87738787Ferrate:

  • Masaharu Nakamura: Hideo Nagashima: J. AM. CHEM. SOC. 2009, 131, 60786079

  • Radical cyclization rate 1.0x105M-1S-1Radical ring open rate 1.3x108M-1S-1

  • Possible catalytic cycle for the (TMEDA)FeAr2-catalyzed crosscoupling reaction.

  • Masaharu Nakamura: J. AM. CHEM. SOC. 2010, 132, 1067410676features: (1) divalent iron (+II oxidation state),(2) neutral complex, (3) coordinatively unsaturated,(4) having sufficient spin density on the iron center.

  • Shi, ZJ: J. AM. CHEM. SOC. 2009, 131, 1465614657

  • Oxidative homo-couplingCahiez: J. AM. CHEM. SOC. 2007, 129, 13788-13789

  • Angew. Chem. Int. Ed. 2009, 48, 2969 2972benzyl-, allyl-, or tertiary alkylzinc give low yields

  • J. AM. CHEM. SOC. 2008, 130, 58585859Cross-coupling based on C-H activation/C-C bond formation:Cheap iron and mild condition 0oC

  • Angew. Chem. Int. Ed. 2009, 48, 2925 2928

  • J. AM. CHEM. SOC. 2010, 132, 55685569

  • Yu, XQ: Angew. Chem. Int. Ed. 2008, 47, 8897 8900Lei AW: Angew. Chem. Int. Ed. 2010, 49, 2004 2008

  • Charette: J. AM. CHEM. SOC. 2010, 132, 15141516

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