Using COB(OC)OC, Brc1ccc2c(-c3ccccc3)c(-c3ccccc3)oc2c1 to produce OB(O)c1ccc2c(-c3ccccc3)c(-c3ccccc3)oc2c1, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.