One-pot Synthesis Of Substituted Pyrrole Carboxylate Compounds Under The Microwave Background

With hydrobromic acid and hydrogen peroxide as the brominating agent, substitutedacetophenones were brominated to give three kinds of α-bromo acetophenone derivatives.And then studying on bromination reaction conditions, the results show that differentsubstituted acetophenones obtains different bromination products. Containing electron-richgroups on the benzene ring, and products with the α-carbonyl group and benzene ring werebrominated, on the contrary, it is only to obtain α-carbonyl brominated product.Using the general method, α-bromo acetophenone, ethyl acetoacetate and aniline asreaction materials, one pot synthesis of N-substituted-2-methyl-5-substitutedpyrrolyl-3-carboxylate derivatives. Discuss amount of reactants, reaction solvents, reactiontime, reaction temperature, and vary catalysts, the general method obtains the highest yieldof30%, and different amino compounds to the reaction, the desired results are not got.Therefore, the general method is not suitable for one pot synthesis ofN-substituted-2-methyl-5-substituted pyrrolyl-3-carboxylate derivatives.Using the microwave method, α-bromo acetophenone, ethyl acetoacetate and differentamines as reaction materials, a total of eighteen novle N-substituted-2-methyl-5-substitutedpyrrolyl-3-carboxylate derivatives had been synthesized and the structures of these productswere confirmed by IR and NMR. Discuss reaction solvents, reaction time, reactiontemperature, and microwave power, and then a optimal reaction condition was defined. Anddifferent substituted amine compounds are suitable for this reaction. Moreover,electron-rich groups and electron-poor groups on the benzene ring are also suitable for onepot synthesis of N-substituted-2-methyl-5-substituted pyrrolyl-3-carboxylate derivativesunder the microwave background.