Azepinium synthesis

Reaction of the cyclometallated derivative of phenyl-2-pyridylketone 73 leads to indenol-chelated, palladium-containing derivatives 74. Here, incorporating an electrophilic (CO) function in the starting palladacycle signifies that, following alkyne insertion in the Pd-C bond, an intramolecular attack of the vinyl palladated unit on the metal-bound, activated CO function occurs. This is in sharp contrast to the reaction described in Scheme 9 whereby incorporating a nucleophilic, masked, secondary amine function leads to indole derivatives 40 and to the azepinium synthesis from the metallated benzylpyridine complex 34. Therefore, these reactions are rather sensitive to the nature of other potentially reactive functions within the metallacyclic framework. 

H-Azepinium perchlorate, 6,7-dihydro-formation, 7, 512 Azepinoindoles synthesis, 7, 537 Azepin-2-one, hexahydro-chlorination, 7, 517 synthesis, 7, 530 Azepin-2-one, 3-hydroxy-methylation, 7, 518... 

Key Words Iminium, Oxaziridinium, Oxaziridine, Ketiminium, Oxone, Tetra-phenylphosphonium monoperoxysulphate, Isopinocampheylamine, Alkene, Epoxide, Enantiomeric excess. Asymmetric synthesis, Organocatalysis, 2-(2-Bromoethyl)benzaldehyde, Levcromakalim, Dihydroisoquinolinium, Spiro, Azepinium, Benzopyran, Dielectric constant, Binol. 2008 Elsevier B.v. 

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