Research On The Synthesis And Photophysical Properties Of Phenyl Isocyanide Pentafluorophenyl Gold(Ⅰ) Complexes With Different Length Of Alkyl Chain

Color and luminescence switching materials mean that the materials can change their luminescence color and/or intensity under external stimulus signals such as light,electricity,temperature,vapour and pressure.These materials possess abilities of sensing,response,self-recovering under external stimulus.Such new smart materials enjoy broad application prospects in chemical sensors,artificial intelligence,constructions,military affairs,and medical fields.Recently,fluorogens with aggregation-induced emission(AIE)properties have shown great potential to be developed as bioprobe,which are highly emissive in aggregation state.Therefore,it is of great significance to design a series of photoluminescence materials with multiple stimulus responses.In this work,using phenyl isocyanide as ligand,we designed and synthesized seventeen mono-and bis-pentafluorophenyl gold(Ⅰ)complexes Ⅰ-1～Ⅰ-8 and Ⅱ-1-Ⅱ-9 with different alkyl chains.The effects of the alkyl chain lengths on the photophysical properties of these complexes in solution and solid-state were studied as follows:Firstly,we designed and synthesized eight pentafluorophenyl(phenyl isocyanide)gold(Ⅰ)complexes Ⅰ-1-Ⅰ-8 with different alkyl chains.All complexes were characterized by 1H NMR,13C NMR,19F NMR and elemental analysis.Complexes 1-2 and 1-5 were confirmed by X-ray single crystal diffraction.The photophysical properties of these complexes were studied systematically by ultraviolet spectra,fluorescence spectra,and X-ray powder diffraction.The results indecated that different alkyl chain lengths can hardly effect on the solution photophysical properties of these complexes,but have more or less effects on their solid-state photophysical properties.All complexes showed reversible mechanochromic properties.A "polymorph doping" concept of complex 1-5 represents a promising design strategy to prepare white-emissive materials from single compounds.Secondly,we designed and synthesized nine[(C6F5Au)2(μ-1,4-diisocyanobenzene)]derivatives Ⅱ-1-Ⅱ-9 with different alkyl chains.All complexes were characterized by 1H NMR,13C NMR,19F NMR and elemental analysis.Complexes Ⅱ-3,Ⅱ-5,Ⅱ-6,Ⅱ-7,Ⅱ-8,and Ⅱ-9 were confirmed by X-ray single crystal diffraction.The results indicated that all of them with aggregation-induced emission properties.And the maximum aggregation luminescence intensities of these complexes were decreased with the increasing of their alkyl chain length.Complexes Ⅱ-1 and Ⅱ-2 showed reversible thermochromic properties.All complexes showed mechanochromic properties,in which the complexes Ⅱ-4-Ⅱ-9 showed self-recovering mechanochromic properties,and the rates of their recovery were increased by increasing their alkyl chain length.