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Three simple bisamide derivatives (G1, G2 and G3) with different structural modifications were synthesized with easy synthetic procedures in order to test their gel behaviour. The outcomes showed that hydrogen bonding was essential in gel formation; for this reason, only G1 provided satisfactory gels. The presence of methoxy groups in G2 and the alkyl chains in G3 hindered the hydrogen bonding between N-H and C=O that occurred G1. In addition, G1 provided thermally and mechanical stable gels, as confirmed with Tsol and rheology experiments. The gels of G1 were also responsive under pH stimuli and were employed as a vehicle for drug crystallization, causing a change in polymorphism in the presence of flufenamic acid and therefore providing the most thermodynamically stable form III compared with metastable form IV obtained from solution crystallization.

Formation of all-carbon-substituted quaternary carbons is a key challenge in organic and medicinal chemistry. We report a cobalt-catalyzed C(sp3)–C(sp3) cross-coupling that allows for the introduction of benzyl, heteroarylmethylzinc and allyl groups to halo-carbonyl substrates. The cross-coupling reaction is selective for C(sp3)-over C(sp2)-halides, in contrast to most used catalytic metals, and allows access to novel scaffolds of pharmaceutical interest. NMR mechanistic studies suggest the presence of Co(0) complexes as catalytic species., La formación de carbonos cuaternarios totalmente sustituidos con carbono es un desafío clave en la química orgánica y medicinal. Presentamos un acoplamiento cruzado C(sp 3 )–C(sp 3 ) catalizado por cobalto que permite la introducción de grupos bencilo, heteroarilmetilzinc y alilo en sustratos de halocarbonilo. La reacción de acoplamiento cruzado es selectiva para C(sp 3 )-sobre C(sp 2 )-haluros, en contraste con la mayoría de los metales catalíticos utilizados, y permite el acceso a nuevos andamios de interés farmacéutico. Los estudios mecanísticos de RMN sugieren la presencia de complejos de Co(0) como especies catalíticas.

A series of donor-π-acceptor-π-donor (D-π-A-π-D) benzoazole dyes with 2H-benzo[d][1,2,3]triazole or BTD cores have been prepared and their photophysical properties characterized. The properties of these compounds display remarkable differences, mainly as a result of the electron-donor substituent. Dyes with the best properties have visible-light absorption over λ=400 nm, large Stokes shifts in the range of about 3500-6400 cm-1 , and good fluorescence emission with quantum yields of up to 0.78. The two-photon absorption properties were also studied to establish the relationship between structure and properties in the different compounds synthesized. These results provided cross sections of up to 1500 GM, with a predominance of S2 ←S0 transitions and a high charge-transfer character. Time-dependent DFT calculations supported the experimental results.

2H-Benzo[d]1,2,3-triazole derivatives with a range of chemical functionalities showed significant organogel formation, particularly bis-amide derivative 4e which gave robust thermally stable gels, in a range of solvents down to 0.1 wt%. The gelators proved responsive under pH stimuli or to the presence of metal cations. The gels also proved to be useful vehicles to crystallize pharmaceutical drugs, resulting in a change in polymorphic outcome in the case of sulfathiazole compared to the solution crystallization outcome.