Dithiacyclophanes incorporating thieno[2,3-b]thiophene have been synthesized, in order to investigate the nonlinear optical properties of donor–acceptor cyclophane 7. Cyclophane 7 displayed significantly higher first hyperpolarizability β (21.6×10 −30 esu) compared to model 10 (9.58×10 −30 esu). Relatively higher β in 7 presumably arises from an extra electron redistribution arising from through-space charge transfer, a feature lacking in 10. Moreover, the thermal decomposition temperature of 7 (300°C) is higher than that reported for the NLO prototype DANS (295°C).