Search

A series of coordination polymers (CPs), some of them featuring an unusual architecture, have been constructed by treatment of RSCH2C≡CCH2SR (R = C6H11L1, t-Bu L2) with CuX (X = Cl, Br, I) and CuX2. The outcome of the reaction of L1 with CuI depends on the metal-to-ligand ratio. Treatment of CuI with L1 in a 2 : 1 ratio affords the luminescent 2D CP [Cu4I4(μ-L1)2]n (CP1), whose grid-shaped network is built upon Cu4(μ3-I)4 cubane-like clusters as secondary building units (SBUs), interconnected via bridging L1 ligands. The use of a 1 : 1 ratio gives a material, whose particularity is the coexistence of two topological isomers within the unit cell. The first one, [{Cu(μ2-I)2Cu}(μ-L1)2]n (CP2), consists of 1D ribbons. The second isomer having a 0D topology, [{Cu(μ2-I)2Cu}(μ-L1)2] D1, is built upon discrete molecular complexes, whose dinuclear [Cu(μ2-I)2Cu] rhomboid-shaped core is spanned by two bridging L1 ligands. Mixing CuBr with L1 in MeCN solution leads to an isostructural material incorporating both 0D [{Cu(μ2-Br)2Cu}(μ-L1)2] complex D2 along with the 1D isomer [{Cu(μ2-Br)2Cu}(μ-L1)2]n (CP3). However, only the 1D CP [{Cu(μ2-Cl)2Cu}(μ-L1)2]n (CP4) results from complexation of L1 with CuCl. A stoichiometry-dependence is also noticed upon treatment of CuI with L2. Conducting the reaction in a 2 : 1 ratio yields the luminescent 2D CP [Cu4I4(μ-L2)2]n (CP5), whereas mixing equimolar amounts of the reactants produces 2D CP [{Cu(μ2-I)2Cu}(μ-L2)2]n (CP6). Structurally similar 2D CPs [{Cu(μ2-X)2Cu}(μ-L2)2]n (CP8 and CP9) result from complexation of L2 on CuBr or CuCl, respectively. Treatment of L2 with an excess of CuBr or CuBr2 in refluxing acetonitrile led to the transfer of Br to the acetylenic triple bond, generating an olefinic halogenated dithioether ligand Bu L3 that coordinates to CuBr to generate a 1D network [{Cu(μ2-Br)2Cu}(CH3CN)(μ-L3)]n (CP9). Using different conditions (propionitrile at 293 K), the reaction of L2 and excess CuBr led to the formation of a 2D network [{Cu(μ2-Br)2Cu}(μ-L2)(μ-L3)]n (CP10) incorporating both L2 and L3 in an alternating manner as assembling ligands. An isostructural chloro-analogue 2D [{Cu(μ2-Cl)2Cu}(μ-L2)(μ-L4)]n (CP11) was obtained using CuCl or CuCl2. The crystallographic work is completed by thermal analyses and investigation of the luminescence properties of CP1 and CP5 at 77 and 298 K. [ABSTRACT FROM AUTHOR]

With the aim to elaborate novel and inexpensive sulphur-rich materials featuring unusual network architectures, the coordination chemistry of the tetradentate thiaheterocycle 1,2-di(1,3-dithian-2-yl)ethane L1 ligand toward CuX and HgX2 salts was investigated. When L1 is reacted with CuI in a 1 : 1 ratio, a two-dimensional CP [{Cu(μ2-I)2Cu}(μ2-L1)]n (CP1) is formed, in which two out of four S atoms of L1 remain non-coordinated. Upon treatment of L1 with CuI in a 1 : 2 ratio, [{Cu(μ2-I)2Cu}(μ4-L1)]n (CP2) is obtained, in which each S atom of L1 coordinates to one copper centre forming a 2D layer. Raising the ligand-to-CuI ratio to 1 : 4 affords the 2D material [{Cu(μ4-I)(μ2-I)Cu}2(μ4-L1)]n (CP3), in which [Cu(μ4-I)(μ2-I)Cu]n ribbons are interconnected through μ4-bridging L1 ligands. Upon the reaction of L1 with CuBr in a 1 : 2 ratio, a 2D CP [{Cu(μ2-Br)}2(μ2-L1)(μ4-L1)0.5]n (CP4) is formed at room temperature and a 2D CP [{Cu(μ2-Br)}2(μ4-L1)]n (CP5) is obtained in refluxing propionitrile. In CP4 and CP5 Cu atoms are bridged by a single μ2-Br ligand giving rise to [Cu(μ2-Br)Cu]n ribbons but CP4 differs from CP5 from the metal to ligand ratio and the presence of non-coordinated S atoms. Employing a 1 : 3 ratio, a 1D ribbon [{Cu(μ2-Br)}3(MeCN)(μ4-L1)]n (CP6) is generated, that contains both tetrahedral and trigonal copper atoms. CP6 also presents two different L1 ligands that differ by the coordination mode of the sulphur atoms (S acting as 2 or as 4 electron-donor). With CuCl, a 2D network [{Cu(μ2-Cl)2Cu}(μ4-L1)]n (CP7) is generated. L1 coordinates also on HgX2 salts to yield CPs whose architecture depends on the ligand-to-metal ratio. The meander-shaped 1D CP [(HgI2)(μ2-L1)]n (CP8) and the linear 1D ribbons of CP9 and CP12 [(HgX2)(μ2-L1)]n (X = Br, Cl) result from treatment with L1 in a 1 : 1 ratio. In the case of HgBr2, using a 2 : 1 metal-to-ligand ratio, 1D polymeric [{BrHg(μ2-Br)2HgBr}(μ2-L1)] (CP10) is produced. HgI2 and HgBr2 have also been reacted with 2-methyl-1,3-dithiane L2 yielding the molecular complexes [{IHg(μ2-I)2HgI}(κ1-L2)2] (D1) and [HgBr2(κ1-L2)2] (M1). Two heterometallic 1D materials [{IHg(μ2-I)2HgI(μ2-I)2{Cu(RCN)2}2(μ2-L1)]n (CP13) and (CP14) result from the treatment of CP1 with HgI2 in MeCN or EtCN. Performing the reaction of CP1 with HgBr2 in acetonitrile produces the zwitterionic 2D material [Cu(MeCN)}(HgIBr2)(μ2-L1)1.5]n (CP15). [ABSTRACT FROM AUTHOR]

The polymeric title compound, [Cu2(C2H3N)2(C3H6S2)2](PF6)2, represents an example of a one-dimensional coordination polymer resulting from the reaction of [Cu(MeCN)4][PF6] with 1,3-dithiolane. The cationic one-dimensional ribbon consists of two copper(I) centers each ligated by one acetonitrile molecule and interconnected through two bridging 1,3-dithiolane ligands. One S-donor site of each ligand is κ¹-bound to Cu, whereas the second S atom acts as a four-electron donor, bridging two Cu atoms in a κ4-bonding mode. The positive charge of each copper cation is compensated for by a hexafluoridophosphate counter-ion. In the crystal, the polymer chains are linked by a series of C--H ⋯F hydrogen bonds, forming a supramolecular framework. [ABSTRACT FROM AUTHOR]

Guided by the principle of biology-oriented synthesis, a collection of compounds with decahydro-4,8-epoxyazulene scaffold occurring in bioactive natural products was synthesized by the rhodium(II)- catalyzed 1,3-dipolar cycloaddition reaction of pentafulvenes and carbonyl ylides. The products can be obtained in moderate to high yields, with moderate enantioselectivity and excellent diastereoselectivity and regioselectivity. [ABSTRACT FROM AUTHOR]

With the aim to elaborate novel and inexpensive sulphur-rich materials featuring unusual network architectures, the coordination chemistry of the tetradentate thiaheterocycle 1,2-di(1,3-dithian-2-yl)ethane L1 ligand toward CuX and HgX 2 salts was investigated. When L1 is reacted with CuI in a 1 : 1 ratio, a two-dimensional CP [{Cu(μ 2 -I) 2 Cu}(μ 2 -L1)] n (CP1) is formed, in which two out of four S atoms of L1 remain non-coordinated. Upon treatment of L1 with CuI in a 1 : 2 ratio, [{Cu(μ 2 -I) 2 Cu}(μ 4 -L1)] n (CP2) is obtained, in which each S atom of L1 coordinates to one copper centre forming a 2D layer. Raising the ligand-to-CuI ratio to 1 : 4 affords the 2D material [{Cu(μ 4 -I)(μ 2 -I)Cu} 2 (μ 4 -L1)] n (CP3), in which [Cu(μ 4 -I)(μ 2 -I)Cu] n ribbons are interconnected through μ 4 -bridging L1 ligands. Upon the reaction of L1 with CuBr in a 1 : 2 ratio, a 2D CP [{Cu(μ 2 -Br)} 2 (μ 2 -L1)(μ 4 -L1) 0.5 ] n (CP4) is formed at room temperature and a 2D CP [{Cu(μ 2 -Br)} 2 (μ 4 -L1)] n (CP5) is obtained in refluxing propionitrile. In CP4 and CP5 Cu atoms are bridged by a single μ 2 -Br ligand giving rise to [Cu(μ 2 -Br)Cu] n ribbons but CP4 differs from CP5 from the metal to ligand ratio and the presence of non-coordinated S atoms. Employing a 1 : 3 ratio, a 1D ribbon [{Cu(μ 2 -Br)} 3 (MeCN)(μ 4 -L1)] n (CP6) is generated, that contains both tetrahedral and trigonal copper atoms. CP6 also presents two different L1 ligands that differ by the coordination mode of the sulphur atoms (S acting as 2 or as 4 electron-donor). With CuCl, a 2D network [{Cu(μ 2 -Cl) 2 Cu}(μ 4 -L1)] n (CP7) is generated. L1 coordinates also on HgX 2 salts to yield CPs whose architecture depends on the ligand-to-metal ratio. The meander-shaped 1D CP [(HgI 2 )(μ 2 -L1)] n (CP8) and the linear 1D ribbons of CP9 and CP12 [(HgX 2 )(μ 2 -L1)] n (X = Br, Cl) result from treatment with L1 in a 1 : 1 ratio. In the case of HgBr 2 , using a 2 : 1 metal-to-ligand ratio, 1D polymeric [{BrHg(μ 2 -Br) 2 HgBr}(μ 2 -L1)] (CP10) is produced. HgI 2 and HgBr 2 have also been reacted with 2-methyl-1,3-dithiane L2 yielding the molecular complexes [{IHg(μ 2 -I) 2 HgI}(κ 1 -L2) 2 ] (D1) and [HgBr 2 (κ 1 -L2) 2 ] (M1). Two heterometallic 1D materials [{IHg(μ 2 -I) 2 HgI(μ 2 -I) 2 {Cu(RCN) 2 } 2 (μ 2 -L1)] n (CP13) and (CP14) result from the treatment of CP1 with HgI 2 in MeCN or EtCN. Performing the reaction of CP1 with HgBr 2 in acetonitrile produces the zwitterionic 2D material [Cu(MeCN)}(HgIBr 2 )(μ 2 -L1) 1.5 ] n (CP15).

The polymeric title compound, [Cu 2 (C 2 H 3 N) 2 (C 3 H 6 S 2 ) 2 ](PF 6 ) 2 , represents an example of a one-dimensional coordination polymer resulting from the reaction of [Cu(MeCN) 4 ][PF 6 ] with 1,3-di-thiol-ane. The cationic one-dimensional ribbon consists of two copper(I) centers each ligated by one aceto-nitrile mol-ecule and inter-connected through two bridging 1,3-di-thiol-ane ligands. One S-donor site of each ligand is κ 1 -bound to Cu, whereas the second S atom acts as a four-electron donor, bridging two Cu atoms in a κ 4 -bonding mode. The positive charge of each copper cation is compensated for by a hexa-fluorido-phosphate counter-ion. In the crystal, the polymer chains are linked by a series of C-H⋯F hydrogen bonds, forming a supra-molecular framework., (© Knauer et al. 2020.)

The parent compound 1,3-dithiane (L1) was reacted with CuI providing the 1D coordination polymer [{Cu(μ 2 -I) 2 Cu}(μ 2 -L1) 2 ] n (CP1), an isostructural compound [{Cu(μ 2 -Br) 2 Cu}(μ 2 -L1) 2 ] n (CP2) was isolated upon treatment of CuBr with L1. In contrast, treatment of L1 with CuCl results in the formation of 2D polymeric [{Cu(μ 2 -Cl) 2 Cu}(μ 2 -L1)] n (CP3), in which each sulfur atom acts as a 4-electron donor. The 1D compounds [{Cu(μ 2 -X) 2 Cu}(μ 2 -L2) 2 ] n (CP7, X = Br, and CP8, X = Cl) resulting from treatment of 2-methyl-1,3 dithiane (L2) with CuBr and CuCl are isostructural with their CuI homologue [{Cu(μ 2 -I) 2 Cu}(μ 2 -L2) 2 ] n (CP5), reported previously. Using CuCN, a 2D CP of composition [{Cu(μ 2 -CN) 2 Cu}(μ 2 -L2) 2 ] n (CP9) has been isolated. Complexation of 2-isobutyl-1,3-dithiane (L3) on CuI generates a 2D material [{Cu 3 (μ 3 -I)(μ 2 -I) 2 (μ 2 -L3) 2 }] n (CP10), incorporating the usual trinuclear μ 3 -I-capped Cu clusters as SBUs, whereas 2D-polymeric compounds [{Cu(μ 2 -Br) 2 Cu}(μ 2 -L3) 2 ] n (CP11) and [{Cu(μ 2 -Cl) 2 Cu}(μ 2 -L3) 2 ] n (CP12) were obtained with CuBr and CuCl. Treatment of 2-Me 3 Si-1,3-dithiane (L4) with CuX yields the series [{Cu 2 (μ 4 -X)(μ 2 -X)}(μ 2 -L4)] n (CP13-CP15). With 2-phenyl-1,3-dithiane (L5), the outcome of the reaction with CuI depends on the reaction conditions. Reaction with CuI in MeCN provides a 1D ribbon [{Cu(μ 2 -I) 2 Cu}(MeCN) 2 (μ 2 -L5) 2 ] n (CP16), whereas treatment of CuI with L5 in hot EtCN yields 2D-polymeric[{Cu 3 (μ 3 -I)(μ 2 -I) 2 (μ 2 -L5) 2 }] n (CP17). A reversible phase transition from triclinic P1̅ to monoclinic P2 1 / m is observed when recording the structure of CP16 at five different temperatures in the 100-300 K range. Ligand L6 containing a ferrocenyl function at the 2-position was also probed as organometallic dithioether ligand. Reaction of L6 with 1 equiv of CuI produces the 0D dinuclear complex [{Cu(μ 2 -I) 2 Cu}(η 1 -L6) 2 (MeCN) 2 ] (D1), whereas treatment with 2 equiv of CuI affords the novel 1D CP [{Cu(μ 3 -I) 2 Cu}(μ-L6)] n (CP18), in which both S atoms of one L6 molecule span two copper centers of the infinite (CuI) n ribbon. Some selected results of thermal analyses and luminescence measurements are also presented.

The first synthetic access to stable and acyclic 1,3-butadienes with two electron-withdrawing carbonyl groups and their potential to deliver new molecular scaffolds through intriguing endo-selective Diels-Alder cycloadditions are presented. The bicyclic scaffolds produced through the cycloaddition chemistry of electron-deficient dienes afforded potent Hedgehog signaling pathway inhibitors., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A structurally unique and strongly luminescent nonporous 3D coordination polymer (CP) [Cu 8 I 8 (methyldithiane) 4 ] n , CP3, has been prepared in a quasi-anticipated manner from 2-methyl-1,3-dithiane, L1, and CuI. This CP incorporates an unprecedented Cu 8 I 8 cluster built upon two side-fused open cubanes. The crystal structure of CP3 has been determined at 100, 150, 200, 250, 300, 350, and 400 K to study the temperature dependence of the Cu···Cu distances. Two other topological 1D and 2D CPs isomers of formula [{Cu 2 I 2 }(L1) 2 ] n featuring dinuclear {Cu 2 (μ 2 -I) 2 } rhomboids were also obtained independently by control of the reaction conditions. These two CPs convert into CP3 in hot PrCN, thus indicating that this latter material is the thermodynamic product. While CP1 and CP2 are not emissive, CP3 exhibits an intense luminescence due to the incorporation of the octanuclear Cu 8 I 8 clusters as secondary building units within the network. The photophysical properties of CP3 have been investigated and rationalized by means of DFT and TDDFT computing. Furthermore, the thermal stability of these materials has been studied by ATG and DSC analyses. The Raman spectra of CP1-3 have been recorded in the solid state in the 50-500 cm -1 region.

The title compound, [Ge(CH3)3(C7H5O2)], was obtained as a by-product in the synthesis of the corresponding aldehyde. Two slightly different mol-ecules are present in the asymmetric unit. In both mol-ecules, the geometry of the aromatic ring plane is distorted by varying intensities. Additionally, the Ge atoms deviate from the mean aromatic ring planes. Whereas the distance of the Ge atom to the ring plane is only 0.101 (4) Å in the first mol-ecule, this distance is increased to 0.210 (4) Å in the second. In the crystal structure, centrosymmetric O-H⋯O hydrogen-bonded dimers are formed. The title compound is isostructural with the Si analogue [Haberecht et al. (2004 ▶). Acta Cryst. E60, o329-0330].