Raise the anchor! Synthesis, X-ray and NMR characterization of 1,3,5-triazinanes with an axial tert-butyl group

N-t-Bu-N’,N’’-disulfonamide-1,3,5-triazinanes were synthesized and characterized by X-ray single crystal structure analysis. In the course of the X-ray structure elucidation, the first solid experimental evidence of the axial position of the tert-butyl group in unconstrained hexahydro-1,3,5-triazacyclohexanes was obtained. Dynamic low-temperature NMR analysis allowed to fully investigate a rare case of crystallization-driven unanchoring of the tert-butyl group in the chair conformation of saturated sixmembered cycles. DFT calculations show that the use of explicit solvent molecules is necessary to explain the equatorial position of the t-Bu group in solution. Otherwise, the axial conformer is the thermodynamically stable isomer.Fil: Kletskov, Alexey V.. University of Russia; RusiaFil: Zatykina, Anastasya D.. University of Russia; RusiaFil: Grudova, Mariya V.. University of Russia; RusiaFil: Sinelshchikova, Anna A.. Academy of Sciences; RusiaFil: Grigoriev, Mikhail. Academy of Sciences; RusiaFil: Zaytsev, Vladimir P.. University of Russia; RusiaFil: Gil, Diego Mauricio. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Novikov, Roman A.. Academy of Sciences; RusiaFil: Zubkov, Fedor Ivanovich. University of Russia; RusiaFil: Frontera, Antonio. Universidad de las Islas Baleares; Españ

Synthesis, X-ray characterization and theoretical study of 3 a ,6:7,9 a-diepoxybenzo [de] isoquinoline derivatives: on the importance of F⋯O interactions

The synthesis, X-ray characterization and Hirshfeld surface analysis of a series of tetrahydrodiepoxybenzo[de]isoquinoline derivatives obtained by the tandem [4+2] cycloaddition between perfluorobut-2-yne dienophile (F3C–C≡C–CF3) and a row of N,N-bis(furan-2-ylmethyl)-4-Rbenzenesulfonamides (bis-dienes, R = Me, F, Cl, Br, I) are reported in this manuscript. The implementation of kinetic/thermodynamic control allowed to obtain both “pincer”- and “domino”-types adducts in good/moderate yields. In the solid state, most of the pincer adducts form self-assembled dimers (R = Me, Cl, Br, I) and, contrariwise, the domino adducts form 1D supramolecular chains, which are described in detail herein. Remarkably, in the self-assembled dimers, bifurcated halogen bonds involving one fluorine atom of the CF3 group and both O-atoms of sulfonamide are formed, which have been analyzed using DFT calculations, QTAIM and NCIplot computational tools.Fil: Grudova, Mariya V.. Peoples’ Friendship University; RusiaFil: Gil, Diego Mauricio. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química Orgánica; ArgentinaFil: Khrustalev, Victor N.. Peoples’ Friendship University; Rusia. Institute of Organic Chemistry ND. Zelinsky; RusiaFil: Nikitina, Eugeniya V.. Peoples’ Friendship University; RusiaFil: Sinelshchikova, Anna A.. Academy of Sciences. Frumkin Institute of Physical Chemistry and Electrochemistry; RusiaFil: Grigoriev, Mikhail S.. Academy of Sciences. Frumkin Institute of Physical Chemistry and Electrochemistry; RusiaFil: Kletskov, Alexey V.. Peoples’ Friendship University; RusiaFil: Frontera, Antonio. Universidad de las Islas Baleares; EspañaFil: Zubkov, Fedor I.. Peoples’ Friendship University; Rusi

Intramolecular sp2-sp3 disequalization of chemically identical sulfonamide nitrogen atoms: single crystal X-Ray diffraction characterization, hirshfeld surface analysis and DFT calculations of N-substituted hexahydro-1,3,5-triazines

In this manuscript, the synthesis and single crystal X-ray diffraction characterization of four N-substituted 1,3,5-triazinanes are reported along with a detailed analysis of the noncovalent interactions observed in the solid state architecture to these compounds, focusing on C–H···π and C–H···O H-bonding interactions. These noncovalent contacts have been characterized energetically by using DFT calculations and also by Hirshfeld surface analysis. In addition, the supramolecular assemblies have been characterized using the quantum theory of “atoms-in-molecules” (QTAIM) and molecular electrostatic potential (MEP) calculations. The XRD analysis revealed a never before observed feature of the crystalline structure of some molecules: symmetrically substituted 1,3,5-triazacyclohexanes possess two chemically identical sulfonamide nitrogen atoms in different sp2 and sp3-hybridizations.Fil: Kletskov, Alexey V.. University of Russia; RusiaFil: Gil, Diego Mauricio. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; ArgentinaFil: Frontera, Antonio. Universidad de las Islas Baleares; EspañaFil: Zaytsev, Vladimir P.. University of Russia; RusiaFil: Merkulova, Natalia L.. University of Russia; RusiaFil: Beltsova, Ksenia R.. University of Russia; RusiaFil: Sinelshchikova, Anna A.. University of Russia; RusiaFil: Grigoriev, Mikhail S.. University of Russia; RusiaFil: Grudova, Mariya V.. University of Russia; RusiaFil: Zubkov, Fedor I.. University of Russia; Rusi

Unexpected Supramolecular Induced Redox Switching in Sandwich Gd Bisphthalocyaninate

The redox state of the phthalocyanine in sandwich lanthanide complexes is crucial for their applications. In this work, we demonstrate that the cation-induced supramolecular assembly of crown-substituted phthalocyanine lanthanide complexes Ln[(15C5)4Pc]2 can be used to control the redox state of the ligand simultaneously with the coordination sphere of the central metal. We achieve unprecedented redox switching of phthalocyanine ligands in a double-decker Gd(III) complex, resulting from the intramolecular inclusion of potassium cations between the decks with simultaneous twisting of the ligands (the skew angle between them decreases from 44.61° to 0.21°). Such a structural change leads to an increase in the deck to deck distance and drastically facilitates ligand reduction. It was demonstated that this process is anion dependent. Thus, only potassium salts of weak acids (KOPiv, KOAc) induce intramolecular inclusion of cations with redox switching in contrast to salts of strong acids (KBr, KOPic, KSCN and KPF6), where such a redox process does not occur. This breakthrough opens new avenues for controlling the electrochromic properties of phthalocyanines, along with other properties, such as electrical conductivity, optics, etc

Application of New Efficient Hoveyda–Grubbs Catalysts Comprising an N→Ru Coordinate Bond in a Six-Membered Ring for the Synthesis of Natural Product-Like Cyclopenta[b]furo[2,3-c]pyrroles

The ring rearrangement metathesis (RRM) of a trans-cis diastereomer mixture of methyl 3-allyl-3a,6-epoxyisoindole-7-carboxylates derived from cheap, accessible and renewable furan-based precursors in the presence of a new class of Hoveyda–Grubbs-type catalysts, comprising an N→Ru coordinate bond in a six-membered ring, results in the difficult-to-obtain natural product-like cyclopenta[b]furo[2,3-c]pyrroles. In this process, only one diastereomer with a trans-arrangement of the 3-allyl fragment relative to the 3a,6-epoxy bridge enters into the rearrangement, while the cis-isomers polymerize almost completely under the same conditions. The tested catalysts are active in the temperature range from 60 to 120 °C at a concentration of 0.5 mol % and provide better yields of the target tricycles compared to the most popular commercially available second-generation Hoveyda–Grubbs catalyst. The diastereoselectivity of the intramolecular Diels–Alder reaction furan (IMDAF) reaction between starting 1-(furan-2-yl)but-3-en-1-amines and maleic anhydride, leading to 3a,6-epoxyisoindole-7-carboxylates, was studied as well

Supramolecular Assembly of Organophosphonate Diesters Using Paddle-Wheel Complexes: First Examples in Porphyrin Series

The reactions of dicopper tetrapivalate complex Cu₂(μ-OOC-<i>t-</i>Bu)₄­(NCMe)₂ (<b>1</b>) with triphenylphosphine oxide and diethyl phosphite allow paddle-wheel (PW) copper­(II) complexes with phosphorus-containing axial ligands (<b>2</b>, <b>3</b>) to be obtained. When <i>meso</i>-bis­(diethoxyphosphoryl)­porphyrins <b>4M</b> were employed in this ligand exchange reaction, a series of one-dimensional (1D) homo- and heterometallic coordination polymers <b>5M</b> composed of PW subunits and organophosphonate diesters were prepared and characterized by means of single crystal X-ray analysis. Planar porphyrinate <b>4Pd</b> and nonplanar metalloporphyrinates <b>4Cu</b> and <b>4Ni</b> proved to be appropriate molecular structural blocks for assembly of coordination polymers. The structural parameters of the tetrapyrrolic macrocycles incorporated into the polymer chain are determined by the nature of the metal center of the porphyrin moiety. While the geometry of palladium­(II) and nickel­(II) porphyrinates <b>4Pd</b> and <b>4Ni</b> does not change significantly in the polymer chain, saddle-shaped Cu­(II) porphyrinate <b>4Cu</b> exhibits a nearly planar core configuration, being coordinated to the copper centers of PW fragments by two peripheral phosphoryl groups in the polymer chain. The geometry of the tetrapyrrolic core is a key parameter influencing the structural properties of the polymeric materials. For <b>5Pd</b> and for isostructural <b>5Cu</b>, all metal centers of the polymeric chain are aligned. The planar macrocycles of adjacent chains are parallel and are shifted one to another in such a way that the angle between the Pd···P and Pd···Pd directions is 40.4°, and the distance between the nearest palladium­(II) atoms of neighboring chains is 11.668 Å. There is no free volume in these crystals. In the crystals of <b>5Ni</b>, formed by nonplanar porphyrinates, only copper atoms of the PW pivalate moiety are located in one plane, and zigzag chains are formed so that two adjacent tetrapyrrolic macrocycles are located in alternating positions with respect to this plane, the nickel atoms being displaced from this plane by 1.548 Å. This arrangement naturally leads to the formation of regular pores. The resulting channels have an effective cross-section of about 10 × 12 Å and represent ca. 18% of the volume of the crystal. The exchange reaction between the free-base porphyrin <b>4H</b>_<b>2</b> and an excess of copper­(II) pivalate complex <b>1</b> is accompanied by the metalation of the porphyrin core affording the polymer <b>5Cu</b>. Moreover, self-assembly of metalloporphyrinate <b>4Zn</b> is observed under studied experimental conditions, which interferes with the formation of the target mixed coordination polymers

Unusual Formation of a Stable 2D Copper Porphyrin Network

Copper­(II) 5,15-bis­(diethoxyphosphoryl)-10,20-diphenylporphyrin was obtained and characterized by means of cyclic voltammetry, electron paramagnetic resonance, Fourier transform infrared, and UV–visible spectroscopy. Three crystalline forms were grown and studied by means of X-ray diffraction methods (single crystal and powder). The highly electron-withdrawing effect of phosphoryl groups attached directly to the porphyrin macrocycle results in a self-assembling process, with formation of a stable 2D coordination network, which is unusual for copper­(II) porphyrins. The resulting 2D structure is a rare example of an assembly based on copper­(II) porphyrins where the copper­(II) central metal ion is six-coordinated because of a weak interaction with two phosphoryl groups of adjacent porphyrins. The other polymorph of copper­(II) 5,15-bis­(diethoxyphosphoryl)-10,20-diphenylporphyrin contains individual (isolated) porphyrin molecules with four-coordinated copper­(II) in a distorted porphyrin core. This polymorph can be obtained only by slow diffusion of a copper acetate/methanol solution into solutions of free base 5,15-bis­(diethoxyphosphoryl)-10,20-diphenylporphyrin in chloroform. It converts to the 2D structure after dissolution in chloroform followed by consecutive crystallizations, using slow diffusion of hexane. A six-coordinated copper­(II) porphyrin containing two axially coordinated dioxane molecules was also obtained and characterized by X-ray diffraction crystallography. The association of copper­(II) 5,15-bis­(diethoxyphosphoryl)-10,20-diphenylporphyrin in solution was also studied

Unusual Formation of a Stable 2D Copper Porphyrin Network

Copper­(II) 5,15-bis­(diethoxyphosphoryl)-10,20-diphenylporphyrin was obtained and characterized by means of cyclic voltammetry, electron paramagnetic resonance, Fourier transform infrared, and UV–visible spectroscopy. Three crystalline forms were grown and studied by means of X-ray diffraction methods (single crystal and powder). The highly electron-withdrawing effect of phosphoryl groups attached directly to the porphyrin macrocycle results in a self-assembling process, with formation of a stable 2D coordination network, which is unusual for copper­(II) porphyrins. The resulting 2D structure is a rare example of an assembly based on copper­(II) porphyrins where the copper­(II) central metal ion is six-coordinated because of a weak interaction with two phosphoryl groups of adjacent porphyrins. The other polymorph of copper­(II) 5,15-bis­(diethoxyphosphoryl)-10,20-diphenylporphyrin contains individual (isolated) porphyrin molecules with four-coordinated copper­(II) in a distorted porphyrin core. This polymorph can be obtained only by slow diffusion of a copper acetate/methanol solution into solutions of free base 5,15-bis­(diethoxyphosphoryl)-10,20-diphenylporphyrin in chloroform. It converts to the 2D structure after dissolution in chloroform followed by consecutive crystallizations, using slow diffusion of hexane. A six-coordinated copper­(II) porphyrin containing two axially coordinated dioxane molecules was also obtained and characterized by X-ray diffraction crystallography. The association of copper­(II) 5,15-bis­(diethoxyphosphoryl)-10,20-diphenylporphyrin in solution was also studied

Unusual Formation of a Stable 2D Copper Porphyrin Network

Copper­(II) 5,15-bis­(diethoxyphosphoryl)-10,20-diphenylporphyrin was obtained and characterized by means of cyclic voltammetry, electron paramagnetic resonance, Fourier transform infrared, and UV–visible spectroscopy. Three crystalline forms were grown and studied by means of X-ray diffraction methods (single crystal and powder). The highly electron-withdrawing effect of phosphoryl groups attached directly to the porphyrin macrocycle results in a self-assembling process, with formation of a stable 2D coordination network, which is unusual for copper­(II) porphyrins. The resulting 2D structure is a rare example of an assembly based on copper­(II) porphyrins where the copper­(II) central metal ion is six-coordinated because of a weak interaction with two phosphoryl groups of adjacent porphyrins. The other polymorph of copper­(II) 5,15-bis­(diethoxyphosphoryl)-10,20-diphenylporphyrin contains individual (isolated) porphyrin molecules with four-coordinated copper­(II) in a distorted porphyrin core. This polymorph can be obtained only by slow diffusion of a copper acetate/methanol solution into solutions of free base 5,15-bis­(diethoxyphosphoryl)-10,20-diphenylporphyrin in chloroform. It converts to the 2D structure after dissolution in chloroform followed by consecutive crystallizations, using slow diffusion of hexane. A six-coordinated copper­(II) porphyrin containing two axially coordinated dioxane molecules was also obtained and characterized by X-ray diffraction crystallography. The association of copper­(II) 5,15-bis­(diethoxyphosphoryl)-10,20-diphenylporphyrin in solution was also studied