The Studies Of Pd-catalysed C-H And N-H Bonds Double Activation For The Preparation Of Isoquinolinones And Analogues

Isoquinolinone is a basic structural unit, it has been found in many natural plantalkaloid. The study of synthesis of isoquinolinone has drawn great attention bychemists beacause of its unique biological activity. In last two years, chemists wereinterested in the strategy of C-H activation methods to build isoquinolinone unit.Rhodium（III）-catalyzed and Ruthenium（II）-catalyzed synthesis of isoquinolinone andanalogues had been widely reported, and they contain the advantages of efficiencyand atom economy.A novel method about palladium catalyzed synthesis of isoquinolinones has beendeveloped, N-alkoxy benzamide and internal alkyne were used as starting material,Pd（OAc）₂/NaI was the catalytic system, the reaction was carried out in DMF at120oC, under the conditions, a series of isoquinolinones were obtained in good toexcellent yields. Good regioselectivities were also observed during the activationreactions with unsymmetrical alkynes. The structure of the compounds werecharacterized by1H NMR spectra,13C NMR spectra, MS and X-ray analysis.In addition, a novel method of the removal of methoxy group from N-alkoxyisoquinolinone was also described. The method was successfully applied to theone-pot synthesis of N-H isoquinolinones, and achieved good results. We also studiedthe mechanism of the reaction process, and one possible mechanism was proposed.