Herein, we report the synthesis and characterization of ESIPT-based benzothiazole substituted tetraphenylethylene molecules. We also studied their emission behavior in aggregation and solid state.

The reactions of lithiated ethynylferrocene, FcC[triple bond]CLi (Fc = ferrocenyl), with fluoro- and chlorocyclotriphosphazenes, N(3)P(3)X(6) (X = F, Cl), resulted in the formation of stable mono-FcC[triple bond]CP(3)N(3)X(5) [X = F (1), Cl (2)] and geminal bis[(FcC[triple bond]C)(2)PN](X(2)PN)(2) [X = F (3), Cl (4)], ethynylferrocene-substituted cyclophosphazenes. The reactions of 1 and 2 with CpCo(COD) were found to differ in the nature of the sandwich compounds (eta(5)-Cp)Co{eta(4)-C(4)[Fc(2)(N(3)P(3)X(5))(2)]} formed. While the fluorophosphazene-derived compound 1 yielded both cis and trans isomers of the cyclobutadiene complexes 5 and 6, the chlorophosphazene-derived compound 2 was found to give only the trans-cyclophosphazene-disubstituted cyclobutadiene compound 7. The reaction of 3 with CpCo(COD) was found to give the compound (eta(5)-Cp)Co{eta(4)-C(4)-1,3-(Fc)(2)-2,4-[NP(C[triple bond]CFc)(NPF(2))(2)](2)} (8) having one of the alkyne units of the cyclophosphazene moiety of 3 remaining unreacted even after reaction with an excess of CpCo(COD). The first click reactions of ethynylferrocene-derived cyclophosphazenes have been carried out by reacting 1 and 4 with benzyl azide, resulting in novel mono- and disubstituted cyclophosphazene-derived 1,2,3-triazoles. The reaction of 1 with benzyl azide yielded two positional isomers of the 1,2,3-triazole, (1-PhCH(2), 4-Fc, 5-P(3)N(3)F(5))C(2)N(3) (9), and (1-PhCH(2), 4-P(3)N(3)F(5), 5-Fc)C(2)N(3) (10), with the latter having a benzyl group in the vicinity of the ferrocene unit as the major product. A similar reaction of 4 with benzyl azide was found to yield five triazole-based products, with two, [(1-PhCH(2)-4-FcC(2)N(3))(C[triple bond]CFc)PN](PNCl(2))(2) (11) and [(1-PhCH(2)-5-Fc-C(2)N(3))(C[triple bond]CFc)PN](PNCl(2))(2) (12), having one unreacted alkyne unit in the molecule. Among the bis-triazole-derived chlorophosphazenes [(1-PhCH(2)-4-Fc-C(2)N(3))(2)PN](PNCl(2))(2) (13), [(1-PhCH(2)-4-Fc-C(2)N(3))(1-PhCH(2)-5-Fc-C(2)N(3))PN](PNCl(2))(2)] (14), and [(1-PhCH(2)-5-Fc-C(2)N(3))(2)PN](PNCl(2))(2) (15), the unsymmetrically disubstituted bis-triazole compound 14 was found to be the major product. The fluorophosphazene-derived triazole 10 was found to readily form a disubstituted square-planar complex trans-[(1-PhCH(2)-4-P(3)N(3)F(5)-5-Fc)C(2)N(3)](2)PdCl(2) (16) with PdCl(2)(PhCN)(2). All of the new ferrocene- and cyclophosphazene-derived compounds except 8 and 12 have also been structurally characterized.

The first examples of ring-closing metathesis (RCM) reactions of a series of terminal alkene-derived cyclic phosphazenes have been carried out. The tetrakis-, hexakis-, and octakis(allyloxy)cyclophosphazenes (NPPh(2))(NP(OCH(2)CH=CH(2))(2))(2) (1), N(3)P(3)(OCH(2)CH=CH(2))(6) (2), and N(4)P(4)(OCH(2)CH=CH(2))(8) (3) and the tetrakis(allyloxy)-S-phenylthionylphosphazene (NS(O)Ph)[NP(OCH(2)CH=CH(2))(2)](2) (4) were prepared by the reactions of CH(2)=CHCH(2)ONa with the cyclophosphazenes (NPPh(2))(NPCl(2))(2), N(3)P(3)Cl(6), and N(4)P(4)Cl(8) and the S-phenylthionylphosphazene (NS(O)Ph)(NPCl(2))(2). The reactions of 1-4 with Grubbs first-generation olefin metathesis catalyst Cl(2)Ru=CHPh(PCy(3))(2) resulted in the selective formation of seven-membered di-, tri-, and tetraspirocyclic phosphazene compounds (NPPh(2))[NP(OCH(2)CH=CHCH(2)O)](2) (5), N(3)P(3)(OCH(2)CH=CHCH(2)O)(3) (6), and N(4)P(4)(OCH(2)CH=CHCH(2)O)(4) (7) and the dispirocyclic S-phenylthionylphosphazene compound (NS(O)Ph)[NP(OCH(2)CH=CHCH(2)O)](2) (8). X-ray structural studies of 5-8 indicated that the double bond of the spiro-substituted cycloalkene units is in the cis orientation in these compounds. In contrast to the reactions of 1-4, RCM reactions of the homoallyloxy-derived cyclophosphazene and thionylphosphazene (NPPh(2))[NP(OCH(2)CH(2)CH=CH(2))(2)](2) (9) and (NS(O)Ph)[NP(OCH(2)CH(2)CH=CH(2))(2)](2) (10) with the same catalyst resulted in the formation of 11-membered diansa compounds NPPh(2)[NP(OCH(2)CH(2)CH=CHCH(2)CH(2)O)](2) (11) and (NS(O)Ph)[NP(OCH(2)CH(2)CH=CHCH(2)CH(2)O)](2) (13) and the intermolecular doubly bridged ansa-dibino-ansa compounds 12 and 14. The X-ray structural studies of compounds 11 and 13 indicated that the double bonds of the ansa-substituted cycloalkene units are in the trans orientation in these compounds. The geminal bis(homoallyloxy)tetraphenylcyclotriphosphazene [NPPh(2)](2)[NP(OCH(2)CH(2)CH=CH(2))(2)] (15) upon RCM with Grubbs first- and second-generation catalysts gave the spirocyclic product [NPPh(2)](2)[NP(OCH(2)CH(2)CH=CHCH(2)CH(2)O)] (16) along with the geminal dibino-substituted dimeric compound [NPPh(2)](2)[NP(OCH(2)CH(2)CH=CHCH(2)CH(2)O)(2)PN][NPPh(2)](2) (17) as the major product. The dibino compound 17, upon reaction with the Grubbs second-generation catalyst, was found to undergo a unique ring-opening metathesis reaction, opening up the bino bridges and partially converting to the spirocyclic compound 16.

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Epoxy resins of different molecular weights were prepared from epichlorohydrin and 4,4'-sulfonyldiphenol (SDP) and from epichlorohydrin and bisphenol A (BA). They were cured at high temperatures with four different crosslinking agents, including aliphatic and aromatic amines. The thermal behaviour of these cured epoxy resins was studied. From the IPDT and IDT data it was observed that sulfone epoxy resins were thermally more stable than bisphenol A epoxy resins. The activation energies of thermal degradation of the resins were calculated and the implications of these results are discussed. ZUSAMMENFASSUNG :Es wurden Epoxidharze mit unterschiedlichen Molekulargewichten aus Epichlorhydrin und 4,4'-Sulfonyldiphenol (SDP) und aus Epichlorhydrin und Bisphenol A (BA) hergestellt . Sie wurden bei hohen Temperaturen mit vier verschiedenen Vernetzern, einschlieBlich aliphatischer und aromatischer Amine, gehktet. Das thermische Verhalten dieser geharteten Epoxidharze wurde untersucht. Aus den Zersetzungstemperaturen wurde entnommen, dalj Sulfon-Epoxidharze thermisch stabiler als Bisphe-no1 A-Epoxidharze sind. Die Aktivierungsenergien des thermischen Abbaus dieser Harze wurden berechnet, und die Folgerungen aus diesen Ergebnissen werden diskutiert .

We have developed a novel isonicotiamide-based fluorescent "turn-on" chemosensor 1 for the selective detection of Zn(2+) and HSO4(-). The sensor 1 can detect Zn(2+) and HSO4(-) with a detection limit down to the nanomolar level by forming a complex in 1 : 1 stoichiometry in the presence of other anions and 2 : 1 in presence of cations in aqueous solution. Density functional theory calculations on 1 and the 1-Zn(2+)/HSO4(-) complexes are consistent with the experimental results. We have successfully utilized the above cation and anion for the fabrication of INHIBIT molecular logic gates. Furthermore the receptor 1 successfully detected the Zn(2+) and HSO4(-) ions in HeLa cells cultured in Zn(2+) and HSO4(-) enriched medium.

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