“…The naphthalene bis(4,8‐diamino‐1,5‐dicorboxyl)amide (NBA, Figure 1B) building block, pioneered by this Laboratory to address the conformational pitfall of NDI‐arene backbone twisting induced by the imide group steric bulk, is an ideal structural platform for harmonizing both strategies i) and ii) above. [ 22 ] In our initial communication, crystal structures of the isomeric di(thein‐2‐yl) NBA small molecules, 3,7‐NBA‐T 2 and 2,6‐NBA‐T 2 , revealed NBA‐thiophene dihedral angles (θs) of ≈50° versus ≈ 10°, respectively, demonstrating that NBA regioconnectivity can either drive or frustrate backbone planarity. Subsequently, corresponding regioisomeric NBA copolymers with 2,2'‐bithiophene (T2), 3,7‐P(NBA2OD‐T2) and P(NBA2OD‐T2) (Figure 1B), were synthesized, and computational modeling, optical absorption, and X‐ray diffraction indeed reveal that P(NBA2OD‐T2) has significantly greater backbone planarity than 3,7‐P(NBA2OD‐T2) and the NDI‐based P(NDI2OD‐T2).…”