Spiral dibenzosiloles-linked silacycle as pluralistic building core: Facile synthesis, self-assembly and application in latent fingerprints

Abstract

Silacycloalkane molecules are very attractive due to the intriguing structures and properties yet impeded by very limited synthetic methods. Herein a new spiral eight-membered disilacycle linked with dibenzosiloles has been readily synthesized by one-step dimerization of the dibenzosilacyclobutane. As a pluralistic building core the disilacycle molecule with four Br groups provides rich and promising strategies to develop versatile multifunctional materials by classic cross-coupling reactions. The derivatives installed with a variety of aryl groups render them with prominent photoluminescent properties, thermal stability and self-assembly to highly emissive microspheres and microribbons. The emission colors can be finely tuned from deep blue to green with the quantum yield up to 0.96 in solution and 0.34 in the powder form. The compound 4c with four peripheral tetraphenylethylene substituents was demonstrated to have great potential for persistent latent fingerprints (LFPs) on various substrates. The FLPs readily developed by soaking method illustrate the all-round advantages of high sensitivity (25 μM), ultrafast development (3 s), details up to level−3 (mainly referring to the sweat pores), and outstanding stability, attributed to the novel disilacycle core and dendritic AIEgens. This work provides a facile synthetic strategy of the pluralistic silacycle and inspirations for design and development of high-performace multifunctional fluorescent organic materials in practical applications.