Shortly after he went to Barcelona to visit his father's family, but the ship he was traveling in sank off Santa Catarina Island, in Brazil.

In 1851 Molinas represented governor Justo José de Urquiza to the Corrientes government, to coordinate legal and public steps that both governments would make before and after Urquiza's "statement" against the dictator Juan Manuel de Rosas.

Molinas also represented Urquiza to the government of Domingo Crespo, who succeeded Rosa's supporter Pascual Echagüe as governor of Santa Fe Province shortly before the Battle of Caseros.

On 18 March 1857 governor Francisco Domingo Díaz of San Juan Province was overthrown in a revolution.

After the Battle of Pavón (17 September 1861) he remained loyal to Urquiza, and was a member of the Entre Ríos provincial legislature.