After extensive screening of all relevant reaction parameters (see SI, section 5.1), we found that when a solution of 4-trifluoromethyl-phenylsulfonyl hydrazone 1a (1.0 equiv.) as radical acceptor, tetrahydrofuran (THF) as CH donor in the presence of 4, 4'-dichlorobenzophenone (4-Cl2-BP, 20 mol%) as a HAT photo-organocatalyst in trifluorotoluene (0.1 M) was subjected to 40W Kessil PR160L-390 nm irradiation, the targeted alkylated hydrazide 2a could be isolated in excellent yield (Table , Entry 1, 90% yield). In the absence of either the photocatalyst or light, no product formation was observed, thus verifying the photocatalytic nature of this transformation (Table , Entries 2-3). As expected, heating the reaction mixture in the dark also resulted in the quantitative recovery of 1a (Table , Entry 4). When dichloromethane was evaluated as solvent, reduced yields for 2a were observed (Table , Entry 5). A high yield for hydrazide 2a was obtained when equal volumes of THF and trifluorotoluene were used (Table , Entry 6, 91% yield). However, lowering the catalyst loading of 4-Cl2-BP from 20 to 10 mol% resulted in lower yields (Table , Entry 7). Also the electronic properties of the aryl sulfonyl group of the hydrazone were investigated: while the commonly used tosyl (Ar2) and mesityl (Ar4) variants resulted in lower yields (Table , Entries 8 and 10), the presence of a more electron-withdrawing ring completely shuts down the reaction (Table , Entry 9). Of particular note is the practical one-pot protocol in which the hydrazone is generated in situ from 4-(trifluoromethyl)benzaldehyde (70% yield, Table , Entry 11).