Using CC(O[Si](C)(C)C(C)(C)C)c1oc(=O)c2ccccc2c1Br, C=C(OCC)[Sn](CCCC)(CCCC)CCCC to produce C=Cc1c(C(C)O[Si](C)(C)C(C)(C)C)oc(=O)c2ccccc12, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.