Smart molecules with adjustable and reversible ACQ-AIE transformation which could be used as luminescence sensors both in solvent and solid-state are rarely reported. Planar luminophores with strong inter-molecular hydrogen bonds and a rotor might exhibit reversible ACQ-AIE conversion by modulating the inter-molecular hydrogen bonds. As a proof of concept, herein, two smart hydrogen bond dimers (Qufu-1 and Qufu-2) with reversible ACQ-AIE transformation were derived from the renewable bio-feedstock shikimic acid. Qufu-1 and Qufu-2 possessing a novel 4-oxo-3,4-dihydrobenzofuro[2,3-d]pyrimidine key structure and both exhibit crystallization induced ACQ (CIACQ) and precipitation induced AIE (PIAIE) in solid-state. Single crystal analysis indicates that the large planar configuration formed in the dimers of Qufu-1 and Qufu-2 due to the inter-molecular hydrogen bonds, which would result in the strong π-π stacking and ACQ in crystal. The AIE state could be facile realized by breaking the inter-molecular hydrogen bonds and changing the aggregation state from crystal to precipitation. Moreover, ACQ to AIE transformation could also accomplish for Qufu-1 and Qufu-2 in solution by modulating the inter-molecular hydrogen bonds with acid. In addition, three-level structures latent fingerprint identification in real environment and fluorescent sensing of hazardous biogenic amines in food samples were performed with Qufu-1.

具有可调节和可逆 ACQ-AIE 变换、可用作溶剂和固态发光传感器的智能分子很少有报道。具有强分子间氢键和转子的平面发光体可能通过调节分子间氢键表现出可逆的 ACQ-AIE 转换。作为概念证明，本文从可再生生物原料莽草酸中衍生出两种具有可逆 ACQ-AIE 转化的智能氢键二聚体（ Qufu-1和Qufu-2 ）。Qufu-1和Qufu-2拥有新型4-oxo-3,4-二氢苯并呋喃[2,3- d]嘧啶关键结构，并且在固态下均表现出结晶诱导的 ACQ (CIACQ) 和沉淀诱导的 AIE (PIAIE)。单晶分析表明，由于分子间氢键的作用，Qufu-1和Qufu-2二聚体中形成了大的平面构型，这将导致晶体中强烈的π-π堆积和ACQ。通过破坏分子间氢键并将聚集状态从晶体改变为沉淀，可以很容易地实现AIE状态。此外， Qufu-1和Qufu-2也可以完成ACQ到AIE的转换在溶液中通过用酸调节分子间氢键。此外，利用Qufu-1进行了真实环境中的三级结构潜指纹识别以及食品样品中有害生物胺的荧光传感。