Quinolines center formation

A -acetyl groups attached to the aniline have been shown to withstand the Conrad-Limpach reaction. Phenols and alcohols also survived unless in proximity to a reactive center. Jaroszewski reported the formation of 64 by reaction of aniline 63 with ethyl acetoacetate (5). Cyclization under thermal conditions in paraffin gave a mixture of quinolone 65 and quinoline 66. 

For the formation of the 4-ethynylquinoline complexes a mechanism was proposed involving nucleophilic attack of the terminal carbon of the butatrienylidene ligand at the imine carbon, followed by C—C bond formation between the ortho carbon of the N-aryl group and C3 of the butatrienylidene ligand. Deprotonation finally affords 4-ethynylquinoline complexes (Scheme 3.27). Some preference was observed for quinoline formation with the more electron-rich metal centers, whereas... 

Flood looked at an intramolecular Pd(ii) C-H cleavage in which the stereochemistry of the C-H activation was determined. The cyclometallation of (i )-(—)-8-(a-deuterioethyl)quinoline by K2PdCl4 led to the formation of a product in which net retention of configuration at carbon was observed (Equation (20)). A large kinetic isotope effect (kii/k-a = 44) allowed selective activation of the C-H bond, and complexation with leucine provided a diastereotopic center for analysis. 

The quinoline derivative (70) reacts with AlMea to give complexes [(71)-(75)] in which the aluminum centers are coordinated to both the aromatic and imino nitrogen. Reaction temperature and molar ratio govern the product formation which includes methylation of the quinoline ring. ... 

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