Cross-coupling reactions catalyzed by transition metals are currently among the most widely used transformations in organic synthesis. In most of these reactions, the coupling involves the reaction of two complementary functional groups, particularly boronates and halides. For the sake of atom economy and simplicity of the starting materials, it is more advantageous when the coupling involves C–H activation of one substrate lacking a reactive functional group. The present review focuses on the use of metal organic frameworks (MOFs) as solid reusable catalysts to promote cross-coupling reactions involving C–H activation. After general considerations, the review is organized according to the bond formed in the coupling, either C–C or C–heteroatom (N, O, B and X). The purpose of this mini review is to show the performance of MOFs as heterogeneous catalysts in these reactions, combining a high activity due to the large percentage of accessible metal sites and high stability allowing the reuse of the material in consecutive cycles. Comparison with homogeneous analogous catalysts indicates that this improved performance derives from the porosity, large surface area and site isolation and immobilization occurring in the MOFs. Considering the growing interests in these reactions the last section forecasts future developments in these areas in near future.
The addition of an aqueous solution of palladium chloride to an aqueous acetonitrile solution of 4-acetylpyridine (4-Acpy) and KSCN or NaN3 produces new complexes, [Pd(SCN)2(4-Acpy)2] (1) and [Pd(N3)2(4-Acpy)2] (2), at ambient conditions. Complexes 1 and 2 were characterized by elemental analysis, FT-IR, and UV-Visible spectra. The structures of 1 and 2 were determined by single crystal X-ray diffraction. The coordination geometry around the palladium center is distorted square planar in 1 and 2 as the palladium is coordinated with two 4-acetylpyridine and two thiocyanates in 1 or two azide groups in 2. The discrete units of 1 and 2 extend along the a-axis creating a 1 D-chain via non-covalent hydrogen bonds. The extensive non-covalent hydrogen bonds extend the structure of 1 and 2 to 3D-networks. Using MTT assay, the cytotoxic activities of 1 and 2 were screened against two cancer cell lines, HePG-2 (liver cancer) and MCF-7 (breast cancer). The MTT assay revealed that the cytotoxic activity of 1 is stronger than 2 for HePG-2 and MCF-7. Antioxidant and anti‐hemolytic activities of 1 and 2 were examined. Furthermore, the luminescence spectra in the solid state of 1 and 2 are discussed.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Abstract: This study aims to formulate and evaluate Fexofenadine Oral Disintegration Tablets (ODTs), focusing on overcoming patient compliance issues related to taste and swallowing difficulties, especially in elderly and pediatric patients. Fexofenadine, a first-line treatment for type 2 diabetes, is used to enhance rapid dissolution, absorption, and bioavailability. Objectives included preparing tablets using direct compression and evaluating formulations through in-vitro tests such as weight variation, thickness, hardness, friability, drug content, wetting time, dispersion time, disintegration time, and dissolution studies. FTIR spectral analysis confirmed the presence of principal peaks and interactions between drugs and polymers. Results indicated a strong correlation (r = 0.998) between fexofenadine concentration and absorbance values. Tablets exhibited weight and thickness within pharmacoeial limits, with hardness, friability, and drug content meeting acceptable standards. Wetting time and water absorption ratio varied among formulations, with Cross povidone and Croscarmellose sodium showing superior performance. Disintegration times ranged from 17.66±0.51 to 171.83±1.16 seconds, with tablet formulations containing Cross povidone or combinations of super disintegrants (CP + CCS, CP + SSG) demonstrating rapid disintegration. In-vitro dispersion and dissolution studies reaffirmed these findings, suggesting these ODT formulations can significantly improve patient adherence, providing a quick onset of action and enhanced drug bioavailability. Further studies are recommended to establish extended in vivo performance and safety profiles, supporting the efficacy of fexofenadine ODTs in clinical settings.
The structures of 5,5′-bis(naphth-2-yl)- 2,2′-bithiophene (NaT2), 5,5″-bis(naphth-2-yl)-2,2′:5′,2′-terthiophene (NaT3), 5,5‴-bis(naphth-2-yl)-2,2′:5′,2″:5″,2‴-tetrathiophene (NaT4), 5,5″″-bis(naphth-2-yl)-2,2′:5′,2″:5″,2‴:5‴,2″″-quinquethiophene (NaT5) and 5,5′″″-bis(naphth-2-yl)-2,2′:5′,2″:5″,2‴:5‴,2″″:5″″,2′″″-sexithiophene (NaT6) have been optimized at PBE1PBE/6-31G* level of theory. By increasing the chain length (thiophene units) energy gap decreases. The hole reorganization energy also decreases from NaT2–NaT6 . We have observed that mobility of NaT5 and NaT6 can be enhanced by minimizing the polarization and relaxation. The end-capped naphthyl groups have been rotated from 0°–60° in the case study of NaT2 , it was found that hole reorganization energy increases with the increment in angle. Furthermore the charge transport properties of 5,5′-bis(thionaphth-2-yl)-2,2′-bithiophene (TNT2), 5,5″-bis(thionaphth-2-yl)-2,2′:5′,2″-terthiophene (TNT3), and 5,5‴-bis(thionaphth-2-yl)-2,2′:5′,2″:5″,2‴-quaterthiophene (TNT4) have been investigated at the same level of theory. It has been studied that cis isomers have higher hole reorganization energies as compared to trans ones thus these isomers would diminish the mobility.
Advanced poly(O-Toluidine) Sn(II) silicotungstate (POTSn(II)SiO2WO3) ternary nanocomposite synthesized by the extremely well-known simple sol–gel method. We have selected a low-cost o-toluidine monomer initiator and abundantly available metal of divalent tin with the silicon tungstate moieties that may work as the exchange sites for the metal ions. The poly(O-toluidine) Sn(II) silicotungstate was prepared by the oxidative polymerization of o-toluidine by potassium persulphate in situ mixings of the Sn(II) tungstate prepared in the separate conical flask at 5 pH. The obtained composite was characterized by various spectrophotometric techniques viz, SEM-EDX, XRD, TGA, FTIR, and its physicochemical characterization was carried out by determining its potential as an ion-selective membrane electrode. The ion-selective membrane was prepared and characterized for, porosity, swelling, and thickness. Based on high porosity and low thickness, the membrane was selected for further studies for the preparation of the selective membrane electrode and found selective for Cd2+. Based on the calibration curve, the Nernstian response was found near the Nernstian response (29.74), good pH range, and broad selectivity range of the metal ion. This ion-selective membrane electrode would be utilized for the determination of metal in unknown samples.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
