The Directphotoarylation Of Aryl Halides With Unactivated Arenes

Substituted biaryls are omnipresent in the areas of natural products, organicmaterials, as well as biologically active molecules. As a consequence, thedevelopment of much greener and more efficient arylation reactions about thebiaryls formation are still in urgent need under the background of increasingenvironmental concerns.The research work during my Master’s studyis mainly focused on the arylationof aryl halides withunactivated arenes without any additives, which is a greenmethod for the synthesis of biaryls.My research includes the following sections:Part I: Based on the published literatures, the main idea was proposed.Part II:We examined the idea by the specific experiment. In the presence ofUV-irritation,4-Methoxyphenyl iodide can smoothly react with unactived benzeneto afford4-Methoxybiphenyl.PartIII: The optimized reaction conditions of the direct C-H arylation undersimple UV-irradiation wereachieved.Part IV: The substrates scope with a series of aryl halides (iodides, bromidesand chlorides) was studied. Electronic and steric effect on the benzene ring wasexamined. And the law was summed up.Part V: The possible mechanism was proposed based on the experiment dataand reported literatures.The direct arylation of unactivated arenes with aryl halides under simpleUV-irradiation at rt proceeds smoothly to form biaryls. This protocol avoids the useof toxic transition metal catalysts, strong bases, or large amounts of other organic additives. This method provides a new insight into the realization of cost-effectiveand environmentally benign access to biaryls.