Due to the instability and quick hydrolysis of the intermediates, the purity of each isophthaloyl chloride could not be checked. Since the isophthalic acids were partially insoluble under the reaction conditions, the reaction was deemed complete only once the reaction mixture was completely translucent with no noticeable starting material suspended in solution. Once the reactions were complete, an extra 1 h was added to the reaction time before the residual oxalyl chloride and CH2Cl2 was evaporated, collected in a cold trap, and the oxalyl chloride quenched. The reaction mixture was dried in vacuo for 3-12 h. The isolated isophthaloyl chloride intermediates were kept under N2(g) and often used immediately in the next step without further purification. An example has been provided below.