Addressing Synthetic Complexity in Conjugated Polymers: New Synthetic Methods for the Acceptor Units 2,1,3‐benzothiadiazole, 2,3‐dihexylquinoxaline, and 2H‐benzotriazole

In an attempt to address the growing problem of synthetic complexity in conjugated organic polymers, the synthesis of the common acceptor units 2,1,3‐benzothiadiazole (BTD), quinoxaline (Qx), and 2H‐benzotriazole (BTA) have been revisited, along with their dibromo derivatives necessary for use in catalytic cross‐coupling. In addition to reducing the total number of synthetic steps, efforts have been made to reduce hazardous reagents and simplify purification. Synthetic complexity index values for both established and newly reported methods are then generated in order to provide a qualitative evaluation of the reduced contribution of these common building blocks to the synthetic complexity of all materials that contain them.