Visible-light-mediated decarboxylative alkylation of 2-pyridone derivatives via a C3-selective C-H functionalization
Worawat Niwetmarin1,2, Rungroj Saruengkhanphasit1, Chatchakorn Eurtivong1
1Program in Chemical Sciences, Chulabhorn Graduate Institute, Chulabhorn Royal Academy, Bangkok 10210, Thailand. worawat@cgi.ac.th.
Abstract:
A direct C-H functionalization approach to access C3-alkylated 2-pyridone derivatives is reported. This study utilizes N-hydroxyphthalimide (NHPI) esters of various carboxylic acids as sources of alkyl radicals by reductive cleavage under photocatalytic reaction conditions. The carbon-carbon bond formation occurred site-selectively at C3 of 2-pyridone to give the desired products in moderate to good yields. This method enables a faster access to C3-alkylated pyridone compounds which can be applied to the synthesis of small molecule drugs.
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