Aromatic carbon-nitrogen bond

Jiang L, Buchwald SL (2004) Palladium-catalyzed aromatic carbon-nitrogen bond formation. In de Meijere A, Diedeiich F (eds) Metal-catalyzed cross-coupling reactions, 2nd edn. Wiley-VCH, Weinheim... 

A few stoichiometric reactions that formed aromatic carbon nitrogen bonds in the presence of stoichiometric amounts of Pd(PPh3)4 had been reported by Boger and co-workers (Equation (3)).24-26 In the absence of base, the palladium(0) was apparently not regenerated. Pd(PPh3)4 failed to catalyze these reactions when used in a 1 mol.% quantity, but it did induce cyclization in good yield when it was used in stoichiometric amounts 24-26... 

Wolfe, J. P., Wagaw, S., Buchwald, S. L. An Improved Catalyst System for Aromatic Carbon-Nitrogen Bond Formation The Possible Involvement of Bis(Phosphine) Palladium Complexes as Key Intermediates. J. Arrr. Chem. Soc. 1996,118,7215-7216. 

Palladium-Catalyzed Aromatic Carbon-Nitrogen Bond Formation... 

I 13 Palladium-Catalyzed Aromatic Carbon-Nitrogen Bond Formation Pd(OAc)2 (1 mol%)... 

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