Using CCCC[Sn](CCCC)(CCCC)c1cnccn1, COc1cnc(Br)c2[nH]ccc12 to produce COc1cnc(-c2cnccn2)c2[nH]ccc12, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.