▁Following ▁Maz a ' s ▁execution , ▁however , ▁Te jed or ▁joined ▁Un itar ian ▁Party ▁leader ▁General ▁Juan ▁Lav alle , ▁and ▁fled ▁to ▁Chile , ▁where ▁he ▁res umed ▁his ▁law ▁practice ▁and ▁became ▁a ▁friend ▁and ▁al ly ▁of ▁future ▁Chile an ▁President ▁Manuel ▁Mont t . ▁ ▁He ▁returned ▁to ▁Buenos ▁Aires ▁following ▁Ros as ' ▁over throw ▁after ▁the ▁Battle ▁of ▁Cas eros ▁of ▁ 1 8 5 2 , ▁and ▁became ▁a ▁central ▁figure ▁in ▁the ▁movement ▁led ▁by ▁Valent ín ▁Als ina ▁against ▁the ▁Federal ization ▁of ▁Buenos ▁Aires ▁as ▁the ▁national ▁capital ▁through ▁his ▁position ▁of ▁editor - in - ch ief ▁of ▁El ▁Nacional . ▁He ▁opposed ▁the ▁San ▁Nicol ás ▁Ag re ement , ▁Entre ▁R íos ▁leader ▁Just o ▁José ▁de ▁Ur qu iza ' s ▁bid ▁for ▁national ▁unity , ▁and ▁pl otted ▁the ▁assass ination ▁of ▁Ur qu iza ▁with ▁the ▁Log ia ▁Juan - J uan . ▁The ▁attempt ▁on ▁Ur qu iza ▁a ▁failure , ▁a ▁revol t ▁er upt ed ▁in ▁Buenos ▁Aires ▁on ▁September ▁ 1 1 , ▁ 1 8 5 2 , ▁and ▁the ▁latter ▁province ▁became ▁independent ▁of ▁the ▁Confeder ation ▁for ▁the ▁remainder ▁of ▁the ▁de cade . ▁Te jed or ▁then ▁collabor ated ▁with ▁Dal ma cio ▁Vé lez ▁S ars field ▁in ▁the ▁draft ing ▁of ▁a ▁Provin cial ▁Constitution ▁for ▁Buenos ▁Aires , ▁the ▁following ▁year . ▁▁ ▁Te jed or ▁negoti ated ▁the ▁surrender ▁of ▁Buenos ▁Aires