One-Pot Synthesis of 4-Amino-1,2-dihydro-3-quinolinecarboxylic Acid Derivatives

When 2-(methylamino)benzonitrile was treated successively with magnesium bis(diisopropylamide), generated in situ from the reaction of ethylmagnesium bromide and diisopropylamine, and α,β-unsaturated carboxylic acid esters in diethyl ether at 0 °C, conjugate addition and enolate–nitrile coupling proceeded sequentially to give the corresponding 4-amino-1,2-dihydro-3-quinolinecarboxylates in isolated yields ranging from 36 to 79%.