Structural Control of the Photoluminescence of Silole Regioisomers and Their Utility as Sensitive Regiodiscriminating Chemosensors and Efficient Electroluminescent Materials

Abstract

We synthesized a group of silole regioisomers 1(x,y), whose photoluminescence varied dramatically with its regiostructure. By internally hindering the intramolecular rotation, we succeeded in creating a novel silole (1(3,4)) that is strongly luminescent in solutions and whose fluorescence quantum yield in acetone is as high as 83%. We revealed that 1(3,4) was a sensitive chemosensor capable of optically discriminating nitroaromatic regioisomers of p-, o-, and m-nitroanilines. Against general belief, crystal formation of 1(2,4) blue-shifted its emission color and boosted its emission efficiency. The light-emitting diode based on the crystal of 1(2,4) emitted a strong blue light (464 nm) in a high current efficiency (5.86 cd/A).

Aggregation-induced emissions of tetraphenylethene derivatives and their utilities as chemical vapor sensors and in organic light-emitting diodes

“…[12][13][14][15][16] A number of AIE molecules with different structures have subsequently been developed by various research groups. [1][2][3][4][5][6][7][17][18][19][20][21] Many of these AIE dyes, however, are difficult to prepare, involving multistep reactions under stringent conditions.…”

Light-Up of Rhodamine Hydrazide to Generate Emissive Initiator for Polymerization and to Afford Photochromic Polypeptide Metal Complex

“…R-PLG 23 contains higher α-helical chain and its R-O moiety should be more hampered in rotation compared to R-O in R-PLG 13 . Since RIR [23,31,32] is the mechanism responsible for AIE, R-PLG 23 with high content of α-helical chains should be more efficient in emission compared to R-PLG 13 . …”

“…Because of short lifetime and low quantum efficiency of the photoinduced reaction, few investigations [26][27][28][29] were aimed at the photochromic properties of rhodamine amides over the next 30 years. However, recent progress suggested that metal complex (RhM-C, Scheme 1) of rhodamine B salicylaldehyde hydrazine [30] Effective restriction [23,31,32] on the intramolecular rotation of AIE-active luminogens is the main mechanism behind AIE phenomenon. Many luminogens [17][18][19][20][21][22][23] with inherent rotational restriction have been characterized to exhibit AIE activity.…”

“…Investigation of the photochromic properties is therefore the third goal of this study. Effective restriction [23,31,32] on the intramolecular rotation of AIE-active luminogens is the main mechanism behind AIE phenomenon. Many luminogens [17][18][19][20][21][22][23] with inherent rotational restriction have been characterized to exhibit AIE activity.…”

Synthesis of 1,1-Bis(n-butyl, t-butyl)-2,3,4,5-Tetraphenyl-1-Silacyclopentadiene and NMR Study of Their 2,5-Carbodianions

“…C α , C β ,C αi , C βi atoms of 2,3,4,5-tetraphenyl substituted group 14 metallole anions/dianions are participate in π-delocalization of the negative charge on Si atom to give chemical shift changes ongoing from group 14 metalloles to their anions/dianion [9,10,12] . Lately siloles have been attracted by the unique electronic structures [32] and novel aggregation-induced emission (AIE) characteristics [33] . Recently the reduced silole species of 2,5-dilithio-1-silacyclopenta-3-ene have been utilized as a new route to synthesize a silole-containing hyperbranched poly(silylenevinylene) [34,35] .…”