PHENYL-2-BENZOTHIAZOLE-BASED Α-Aminophosphines: SYNTHESIS, CRYSTAL STRUCTURE, AND PHOTOPHYSICAL PROPERTIES

Dual emission of ESIPT-capable 2-(2-hydroxyphenyl)-4-(1H-pyrazol-1-yl)pyrimidines: interplay of fluorescence and phosphorescence

“…The synthetic flexibility of such molecules is based on established synthetic methods of organic chemistry and provides researchers with almost unlimited options for the rational design and modification of various ESIPT-capable scaffolds. [70][71][72][73][74] The tuneability of the properties of ESIPT-fluorophores coupled with their extreme sensitivity to external and internal stimuli makes them an appealing platform for a plethora practical applications. For example, these fluorophores are widely used in analytical chemistry, and the design of ESIPT-capable sensors for analytes of different nature (cations, anions, molecules) has become one of the highly grown interdisciplinary areas in recent years.…”

Pd(II)- and Pt(II)-Assisted P–C Activation/Cyclization Reactions with a Luminescent α-Aminophosphine

“…Relative orientation of N -phenyl and benzothiazole moieties in compound 5 (Figure S9, SI and description therein) differs from that in other reported NH-Pbt derivatives ,,,, due to the absence of intramolecular hydrogen bonds and the presence of shortened N···S contact. − This conformational feature allows the protonated NH-Pbt moiety to be easily recognizable from the nonprotonated N-Pbt.…”

“…41,57,58 The latter transition appears to be the common process for derivatives containing {NH-Pbt} moieties. 38,44,45,59 The relative intensity of the bands in 1 negligibly changes in the excitation wavelength range of 250−400 nm (Figure S12, SI). The UV−vis absorption spectrum of compound 5 resembles that for 1 with the exception for a less-pronounced long wavelength band in the former.…”

“…36−39 They reveal interesting photophysical features, such as excitedstate intramolecular proton transfer (ESIPT) 40,41 and aggregate-induced emission (AIE). 42,43 A new Pbt-based αmethylaminophosphine (PCN, 1) designed in our work has not been synthesized to date, although an oxidized congener, α-methylaminophosphine oxide, 44 and its luminescent Zn complexes were reported recently. 45 Benefiting from coordination to harder Lewis acids, phosphine oxides, however, are generally less prone to coordinate with softer Pd(II) and Pt(II) ions.…”

“…Metal ions in these cases are Ru­(II), Rh­(III), Ir­(III), or Ni­(II); α-aminophosphines bear morpholine, piperazine, or carboxyphenyl substituents at the N atom. ,, Meantime, metal-assisted synthesis can facilitate transformations in ligands, yielding novel architectures, which are otherwise difficult to access. , Therefore, our motivation in this work is to find novel metal-assisted P–C bond activation paths for aminophosphines, especially for luminescent ones, which comprise a photophysically active sulfur–nitrogen heterocycle. In this context, we chose a 2-phenylbenzothiazolyl ( Pbt ) chromophore, whose derivatives are widely used in the design of photoluminescent materials. − They reveal interesting photophysical features, such as excited-state intramolecular proton transfer (ESIPT) , and aggregate-induced emission (AIE). , A new Pbt -based α-methylaminophosphine ( PCN , 1 ) designed in our work has not been synthesized to date, although an oxidized congener, α-methylaminophosphine oxide, and its luminescent Zn complexes were reported recently . Benefiting from coordination to harder Lewis acids, phosphine oxides, however, are generally less prone to coordinate with softer Pd­(II) and Pt­(II) ions.…”