Using BrC1=CC=CC(Br)(c2ccccn2)N1, CCCC[Sn](CCCC)(CCCC)c1ccc(-c2ccccn2)nn1 to produce Brc1cccc(-c2ccc(-c3ccccn3)nn2)n1, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.