Moiety effect on the luminescent property of star-shaped triphenylamine (TPA) derivatives as mechanochromic materials

Abstract

Introducing small moieties, such as –COOH/–COOCH3, on TPA will form supramolecular interactions with different self-assemblies, demonstrating different effects on the MCF luminescent property.

Flanking-donor-controlled diversity in mechanical-force-induced reversible fluorochromism and enhanced emission for carboxylic acid and ester linked solid-state emitters

“…33,34 Typically, as identified earlier, a small amount of pressure could only generate a trivial (10%) increase in the emission Φ f . 22,34…”

“…1. The carboxylic acid derivative AA of a conformationally non-planar triphenylamine (TPA) was reported to have more red-shifted (18 nm) MFC behavior with a reduced quantum yield ( φ f ) than ester analog AE , 22 which displayed an almost-negligible emission shift upon grinding. However, only ester AE exhibited a significant enhancement (1.15 times) in φ f (39.69% to 45.90%) upon applying gentle mechanical force/grinding (MIEE).…”

Multi-stimuli distinct responsive D–A based fluorogen oligomeric tool and efficient detection of TNT vapor

“…Most of the TPA derivatives exhibited twisted conformation. [103][104][105][106] The ordered P1 lattices may have collapsed upon grinding due to the probable formation of the twisted conformation of D-A moieties. The possible p-p stacking in the coplanar conformation between the two oligomeric layered moieties might weaken while grinding P1, resulting in enhanced emission intensity.…”

Crystal structure of tris[4-(naphthalen-1-yl)phenyl]amine

“…Limiting the search to non-polymeric triphenylamines with the same aromatic ring at the three para-positions, there were 19 hits (16 compounds), which included eleven hits (nine compounds) with heteroaromatic rings and eight hits (seven compounds) with phenyl rings. The seven compounds with phenyl rings at the three para-position of the triphenylamine skeleton include tris(biphenyl-4-yl)amine [WEHLIE (Inada et al, 1994); WEHLIE01 (Nieger et al, 2017) Zhang et al, 2017). It is notable that there is only one reported example where the three polycyclic aromatic groups on the periphery of the tripenylamine skeleton are the same, viz.…”