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Understanding the structure–property and structure–morphology correlations of organic luminescent materials is essential in order to employ such materials for desired applications. In this regard, we prepared a library of novel triarylboron-tethered N-boryl-1,8-naphthalimides (TAB-NPIs) 1–6 with variations in their steric and electronic factors. Compounds 1–6 are weakly luminescent in molecularly dispersed state; however, they are strongly luminescent in the aggregated state (THF–H2O mixture). The presence of sterically hindered triarylboryl units in 1–6 endowed these molecules with aggregation-induced emission (AIE) characteristics by preventing cofacial arrangements of NPI moieties, as shown by the supramolecular interactions in the crystal lattice. These structural features preclude excimer formation which can be detrimental to the radiative process in these molecules. Promisingly, these compounds undergo self-assembly and form interesting morphologies such as sheets (1), fibers (2), tubes (3), vesicle...

Reported herein are the synthesis, structure, and intriguing optical characteristics of four new polyaromatic aminoboranes (1–4) bearing dimesitylboron (Mes2B) as electron-accepting unit(s) and diphenylamine (Ph2N) as electron-donating unit(s). These compounds are strongly fluorescent in the solid state. Crystalline samples of 1 and triarylborane-decorated aminoboranes 3 and 4 were found to be blue emitters in the solid state. Compounds 1 and 2 showed aggregation-induced emission (AIE) and aggregation-induced emission color switching, respectively, while 3 and 4 exhibited aggregation-induced emission enhancement. Compounds 1 and 2 showed fascinating mechanofluorochromism upon grinding, and such fluorescence changes are due to a crystalline–amorphous phase transition, as confirmed by powder X-ray diffraction studies (PXRD). Interestingly, a ground sample of 2 was found to be stable and did not revert back upon removal of external stress even after the sample was kept over a long period of time under ambien...

The structure and photophysical properties of two known borylanilines, 4-(dimesitylboryl)aniline (1) and 4-(dimesitylboryl)-3,5-dimethylaniline (2), have been investigated. 1 and 2 have similar don...

The boronic acid (pS)-1,2-NpFcB(OH)2 (1) was obtained by treatment of the lithiated species (pS)-1,2-NpFcLi with B(OiPr)3, followed by acidic workup; subsequent dehydration gave the enantiomericall...

A phosphine-rich hexameric organostannoxanne, [n-BuSn(O)COOL]6 (PDrum; L = p-PPh2-C6H4−), has been synthesized by a 6:6 reaction between [n-BuSn(O)OH]n and p-Ph2PC6H4COOH. 119Sn{1H} NMR of PDrum revealed a single resonance at −481.0 ppm, indicating that it possesses the characteristic drum structure that is well-known among organostannoxanes. Reduction of PdCl2 with NaBH4 in the presence of PDrum afforded a palladium nanocomposite, NP-1. HRTEM of NP-1 indicates that the average nanoparticle size is about 3 nm. The latter has been shown to be very effective in mediating Suzuki-coupling reactions involving a number of different substrates. NP-1 can be recycled, and HRTEM analysis of the used catalyst reveals some agglomeration. Treatment of NP-1 with n-hexane and cooling to −25 °C afforded another palladium nanocomposite, NP-2. The latter also is very effective in catalyzing the Suzuki-coupling reaction. HRTEM of NP-2 shows an average nanoparticle size of about 4.3 nm, which remains nearly unchanged even af...

The binding behavior of the bifunctional Lewis acid (η5-C5H5Fe)2[μ-(C5H3(BPh))2] (3) toward different pyridine derivatives as the Lewis base has been investigated. The 1:1 and 1:2 adducts, 3·D and 3·D2 (donor, D = 4-tert-butylpyridine (tBupy) and 4-dimethylaminopyridine (DMAP)), were obtained by low-temperature crystallization or slow solvent evaporation techniques. The complexes were fully characterized by multinuclear NMR, IR, and elemental analysis. Single-crystal X-ray diffraction data were collected for the 1:1 adduct with DMAP and for both 1:2 adducts, and the marked structural changes upon pyridine binding are discussed in detail. In solution, the 1:2 adducts were found to readily undergo dissociation with formation of the 1:1 adducts as the dominant species at room temperature. Variable-temperature NMR and UV−visible titration studies demonstrate that the first binding process is more than 5 orders of magnitude more favorable than the second binding process.

The reaction of bis(triphenyl)tin oxide, (Ph3Sn)2O, with 2,6-diisopropylphenylphosphate, (ArO)PO3H2 (Ar = 2,6-i-Pr2-C6H3), leads to the formation of a novel double-bicapped hexanuclear monoorganooxotin cage, [(PhSn)6(μ-OH)2(μ3-O)2(μ-OEt)4{(ArO)PO3}4]. This reaction proceeds by a de-arylation reaction involving the cleavage of Sn−C bonds.