A method for producing platform molecules comprising: forming a mixture comprising first and second phenylene rings comprising halogenated carboxylic groups, and a third phenylene ring comprising a desired substituent and a first functionality at a para-position to a second funcitonality; and exposing the mixture to conditions effective to react the first halogenated carboxylic group with the first functionality to produce a first ester bond, and the second halogenated carboxylic group with the second functionality to produce a second ester bond; producing platform molecules comprising terminal groups comprising the first functional group at a position para to first ester bond and the second functional group at a position para to the second ester bond.