Synthetic Study Towards To3-alkyl-3-N-disubstituted Benzofuran-2(3H)-ones

The thesis is divided into two parts. Part one is a review of research progress ofbenzofuran derivatives. Part two described a research of synthetic method ofbenzofuran-2-(3H)ones.In Part One, a short review of synthetic approaches of benzofuran derivatives andtheir further applications in organic synthesis is delivered. Since various benzofuranderivatives could be implemented as intermediates in drug synthesis, it is a hotresearch field for chemists in decades. Methods reviewed in this part are delicatelydesigned and have good yields or compatability. However, limitations are still existedsuch as requirement of expensive catalysts or microwave procedures, or incompatiblewith a wider range of substrates.Part Two is experimental studies of synthetic approach to benzofuran-2-(3H)ones. Based on a new method of ortho-quinone methide generation strategyunder mild base condition, various N-substituted aryl glycine esters are obtained from(ortho-hydroxymethyl)aryl benzoates. In the process of explore the potential usage ofN-substituted aryl glycine esters, we discovered an unreported caesium carbonatemediated Michael-addition/lactonization cascade to synthesize3-alkyl-3-N-substituted benzofuran-2-(3H)ones.