In this combined computational and experimental study, the C−H functionalization of 2‐phenyl pyridine with diazoalkanes was investigated. Initial evaluation by computational methods allowed the evaluation of different metal catalysts and diazoalkanes and their compatibility in this C−H functionalization reaction. With these findings, suitable reaction conditions for the C−H methylation reactions were quickly identified by using highly reactive TMS diazomethane and C−H alkylation reactions with donor/acceptor diazoalkanes, which is applied to a broad scope on alkylation reactions of 2‐aryl pyridines with TMS diazomethane and donor/acceptor diazoalkane (51 examples, up to 98 % yield). [ABSTRACT FROM AUTHOR]