Preparative and regiochemical aspects of the palladium-catalyzed carbonylative coupling of 2-hydroxyaryl iodides with ethynylarenes

The title reaction has been conveniently carried out in DMF at 60°C unakr 1 atm of CO pressure using DBU as the base and Pd(OAc)z(DPPF)2 as the catalyst to t@ord generally muhtres offlavones 4 and atuones 5 in varying yields, dependtng on the mbstituents in the both reactants. Factors controlling the regioselectivtty for 4 or 5 formation in thts and in sunilar, previotuly reported . coupling procedwes have been examined

A new versatile solvatochromic amino-macrocycle. From metal ions to cell sensing in solution and in the solid state

A new fluorescent NBD-polyaza-macrocycle sensor (L) was synthesized and studied. The coordination of Cu(II) and Zn(II) in acetonitrile switches on the fluorescence with different emission wavelengths. Crystalline Cu(II) complexes showed solid-state fluorescence. Both the free L and Cu-complexes interact with human leukemic monocyte lymphoma cell line (U937) and both are able to highlight the cell membrane by fluorescence microscopy

The templating effect of diammonium cations on the structural and optical properties of lead bromide perovskites: a guide to design broad light emitters

The templating role in the formation of 2D metal halide perovskites of diammonium cations, such as 1,3-phenylenediammonium (1,3-PDA), 1,3-xylylenediammonium (1,3-XDA), 1,4-phenylenediammonium (1,4-PDA), and 1,4-xylylenediammonium (1,4-XDA) cations, has been investigated. Single-crystal X-ray diffraction confirms the formation of 2D Dion-Jacobon (DJ) perovskites for all the cations except for the 1,3-XDA cation leading to a so-called 0D perovskitoid. The analysis of the structural data showed a higher distortion degree for the systems containing a shorter cation, namely 1,4-PDA. A detailed spectroscopic investigation, with both static and time-resolved photoluminescence spectroscopy, revealed a broadband emissive component at room temperature with hundreds of nanometers of bandwidth when 1,3-PDA and 1,4-PDA cations are present, while a narrow peak is found for the longer cation, i.e. 1,4-XDA. A broadband emission arises in this last sample as well by decreasing temperature. Such a broad emission, as indicated by the analysis of the power and temperature dependence of the PL, can be attributed to trap-mediated excitonic recombination or STEs, and the trend in emissive properties can be correlated with the different levels of octahedral distortions. The novel systems reported in this work enlarge the family of broadband emitters and add further insights to develop efficient perovskite-based broadband and white light emitters

A New Approach to the Synthesis of Heteronuclear Propeller-like Single Molecule Magnets

Propeller-like [Fe4(L)2(dk)6] complexes, in which Hdk is a β-diketone and H3L is a tripodal alcohol, R–C-(CH2OH)3, exhibit tunable magnetic anisotropy barriers and retain their magnetic memory effect when chemically anchored on metal surfaces. Heteronuclear analogues of these M4 complexes have been sought to afford a library of compounds with different total spin (S) values, but synthetic efforts described so far gave solid solutions containing M4 in addition to the desired M3M’ species. We now present a novel synthetic route to M3M’ complexes featuring a central chromium(III) ion. The three-step preparation goes through coordination of CrIII by two equivalents of tripodal alkoxide (R = Et and Ph), followed by reaction of this complex “core” with the peripheral +III metal ions. Products have been characterised by chemical analyses together with 1H-NMR, FTIR, W-band EPR, DC/AC magnetic susceptibility measurements and single crystal X-ray diffractometry. Due to the chemical inertness of CrIII, this route yields 100% pure Fe3Cr complexes without metal scrambling; what is more, it is suitable for designing novel heteronuclear single molecule magnets (SMMs) with a variety of d- and f-metals and R groups