Morpholinium Cations Research Articles

Tris{4-[(2H-tetrazol-5-yl)methyl]morpholinium} dodecatungstophosphate hexahydrate

The title heteropolyoxidotungstate-based inorganic–organic hybrid material, (C6H12N5O)3[W12(PO4)O36]·6H2O, consists of one α-Keggin-type [W12(PO4)O36]3− polyoxidometalate anion (POM), three crystallographically independent 4-[(2H-tetra­zol-5-yl)meth­yl]morpholinium cations and six water mol­ecules of crystallization. The morpholine ring of the cation adopts a chair conformation. The anion shows characteristic features with respect to bond lengths and angles. An extensive network of N—H⋯O, N—H⋯N, O—H⋯O and O—H⋯N hydrogen-bonding inter­actions between the organic cations, inorganic anion and the crystal water mol­ecules lead to a three-dimensional structure. Moreover, six uncoordinated water mol­ecules increase the number of hydrogen bonds in the network and lead to the formation of (H2O)∞ clusters.

Tetrakis{4-[(2H-tetrazol-5-yl)methyl]morpholin-4-ium} dodecatungstosilicate hexahydrate

The crystal structure of the title compound, (C6H12N5O)4[W12(SiO4)O36]·6H2O, consists of an α-Keggin-type [W12(SiO4)O36]4− polyoxidoanion, four [(2H-tetra­zol-5-yl)meth­yl]morpholinium cations and six uncoordinated water mol­ecules. In the cations, the morpholine rings display chair conformations. Extensive N—H⋯O, N—H⋯N, O—H⋯O and O—H⋯N hydrogen bonds are present in the crystal structure.

Vibrational and thermodynamic properties and molecular motions in the incommensurate crystal of morpholinium tetrafluoroborate studied by 1H NMR

Dynamics of molecules in morpholinium tetrafluoroborate, [NH 2(C 2H 4) 2O][BF 4], has been studied in a wide temperature range by means of AC calorimetry, 1H NMR and infrared spectroscopy. Simultaneously, DFT (density functional theory) calculations of the molecular structure and normal vibration frequencies have been performed by using various functionals for initial structural data of the low temperature phase. Infrared spectra of polycrystalline [NH 2(C 2H 4) 2O][BF 4] have been analyzed in a frequency range 4000–400 cm −1. Substantial changes in a temperature evolution of internal modes of both morpholinium cations and [BF 4] − anions are due to the freezing of these moieties motions below 117 K. A dynamic nonequivalence of protons involved in N–H⋯F and N–H⋯O hydrogen bonds has been detected. Heat capacity anomalies around structural phase transitions detected by AC calorimetry (117 and 153 K) have been evaluated and described. A molecular mechanism of the phase transitions is discussed on the basis of presented results.

Aromatic Compounds Mannich Reaction Using Economical Acidic Ionic Liquids Based on Morpholinium Salts as Dual Solvent-Catalysts

Economical acidic ionic liquids containing an alkanesulfonic acid group in a morpholinium cation were found to be effective catalysts for the Mannich reactions of various kinds of aromatic aldehydes, acetophenone and aromatic amines at mild reaction conditions. The satisfactory results were obtained with short reaction time, good yields of the Mannich bases and simplicity in the experimental procedure. These ionic liquids could be recycled and reused for up to five times without considerable decreasing in the catalytic activity.

Morpholinium styphnate

In the title mol­ecular salt (systematic name: morpholinium 3-hy­droxy-2,4,6-trinitro­phenolate), C4H10NO+·C6H2N3O8 −, two of the nitro groups of the anion are close to parallel with the plane of the benzene ring [dihedral angles = 3.46 (9) and 11.60 (10)°] and one is almost perpendicular [dihedral angle = 82.23 (8)°]. An intra­molecular O—H⋯O hydrogen bond occurs in the anion. The morpholinium cation has a slightly distorted chair conformation. In the crystal, the components are linked by simple N—H⋯O and trifurcated N—H⋯(O,O,O) hydrogen bonds.

Acetylation of alcohols and phenols with acetic anhydride under solvent-free conditions using an ionic liquid based on morpholine as a recoverable and reusable catalyst

Rapid and efficient acetylation of alcohols and phenols with acetic anhydride is performed in the presence of economical Bronsted acidic ionic liquids that bear a propanesulfonic acid group on a morpholinium cation as catalysts under solvent-free conditions. [MMPPA][HSO4] (N-methylmorpholinium propanesulfonic acid ammonium hydrogensulfate) was proven to be the most active catalyst, and after removal of water, it could be recycled and reused for up to four times without a noticeable decrease in catalytic activity.

Physicochemical Characterization of Morpholinium Cation Based Protic Ionic Liquids Used As Electrolytes

New protic ionic liquids (PILs) based on the morpholinium, N-methylmorpholinium, and N-ethyl morpholinium cations have been synthesized through a simple and atom-economic neutralization reaction between N-alkyl morpholine and formic acid. Their densities, refractive indices, thermal properties, and electrochemical windows have been measured. The temperature dependence of their dynamic viscosity and ionic conductivity have also been determined. The results allow us to classify them according to a classical Walden diagram and to evaluate their "fragility". In addition, morpholinium based PILs exhibit a large electrochemical window as compared to other protic ionic liquids (up 2.91 V) and possess relatively high ionic conductivities of 10-16.8 mS x cm(-1) at 25 degrees C and 21-29 mS x cm(-1) at 100 degrees C, and a residual conductivity close to 1.0 mS x cm(-1) at -15 degrees C. PIL-water mixtures exhibit high ionic conductivities up to 65 mS x cm(-1) at 25 degrees C and 120 mS x cm(-1) at 100 degrees C for morpholinium formate with water weight fraction w(w) = 0.6. Morpholinium based PILs studied in this work have a low cost and low toxicity, are good ionic liquids, and prove extremely fragile. They have wide applicable perspectives as electrolytes for fuel cell devices, thermal transfer fluids, and acid-catalyzed reaction media as replacements of conventional solvents.

Synthesis and Mesophase Behaviour of Morpholinium Ionic Liquid Crystals

AbstractA novel series of morpholinium salts, N‐alkyl‐N‐methylmorpholinium salts (Mor1,nX, n=10, 12, 14, 16, X=BF4−) and Brönsted acidic N‐hexadecyl morpholinium salts (Mor16X, X=BF4−, CH3SO3− and p‐CH3C6H4SO3−) were synthesized. And their mesomorphic properties were characterized by differential scanning calorimetry and polarized optical microscopy. The single crystal X‐ray diffraction and the detailed temperature dependent small angle X‐ray diffraction were used to investigate the molecular structure of Mor1,16BF4. These results suggested that the favor the formation and stabilization of mesogenic compounds. And hydrogen bonds between the BF4− and morpholinium cations contributed to the conformational change of phase transition of Mor1,16BF4.

Piperidinium, Piperazinium and Morpholinium Ionic Liquid Crystals

Piperidinium, piperazinium and morpholinium cations have been used for the design of ionic liquid crystals. These cations were combined with several types of anions, namely bromide, tetrafluoroborate, hexafluorophosphate, dodecylsulfate, bis(trifluoromethylsulfonyl)imide, dioctylsulfosuccinate, dicyclohexylsulfosuccinate, and dihexylsulfosuccinate. For the bromide salts of piperidinium containing one alkyl chain, the chain length was varied, ranging from 8 to 18 carbon atoms (n = 8, 10, 12, 14, 16, 18). The compounds show a rich mesomorphic behavior. High-ordered smectic phases (crystal smectic E and T phases), smectic A phases, and hexagonal columnar phases were observed, depending on the type of cation and anion. The morpholinium compounds with sulfosuccinate anions showed hexagonal columnar phases at room temperature and a structural model for the self-assembly of these morpholinium compounds into hexagonal columnar phases is proposed.

Dimorpholinium pentachloridoantimonate(III)

The asymmetric unit of the title compound, (C4H10NO)2[SbCl5], consists of two morpholinium cations in chair conformations, and a penta­chloridoanti­monate dianion with the SbIII ion in a slightly distorted square-pyramidal coordination environment. The morpholinium cations are connected to each other by N—H⋯O hydrogen bonds, and they link the chloride anions and the anti­monate SbCl3 group via N—H⋯Cl contacts.

Crystal structure, properties and phase transitions of morpholinium tetrafluoroborate [C 4H 10NO][BF 4

The crystal structure of [C 4H 10NO][BF 4] is determined in the phase I at 160, 180, 240 and 290 K. At room temperature the compound crystallizes in the orthorhombic space group: Pnam. The structure is composed of the morpholinium cations, [C 4H 10NO] +, which form one-dimensional hydrogen bonded chains, and [BF 4] − anions. [C 4H 10NO][BF 4] undergoes two structural phase transformations: second-order at 153 K and first-order at 117/118 K (cooling/heating). The phase transitions are characterized with the differential scanning calorimetry, dilatometric and dielectric techniques. The possible mechanism of the phase transitions in [C 4H 10NO][BF 4] is discussed on the basis of the presented results.

Morpholinium 2,4,6-trinitrophenolate

There are two independent formula units in the asymmetric unit of the title compound, C4H10NO+·C6H2N3O7 −. The morpholinium cations in both mol­ecules are puckered and adopt a chair conformation. Intermolecular N—H⋯O and C—H⋯O inter­actions generate rings of motifs R 2 1(5) and R 1 2(6). The supra­molecular aggregation is completed by the presence of two co-operative hydrogen-bonded networks of further N—H⋯O inter­actions, which generate an infinite one-dimensional chain along the base vector [100]. Two C—H⋯π interactions are also seen.

1H, 13C, and 15N Solid-State NMR Studies of Imidazole- and Morpholine-Based Model Compounds Possessing Halogen and Hydrogen Bonding Capabilities

The halogen and hydrogen bonding interactions present in solid 1-(2,3,3-triiodoallyl)imidazole (1), morpholinium iodide (2), the 1:1 cocrystal 1-(2,3,3-triiodoallyl)imidazole·morpholinium iodide (3), morpholine (4), imidazole (5), and 1-(3-iodopropargyl)imidazole (6) have been investigated by solid-state 1H, 13C, and 15N NMR spectroscopies. Comparison of the 15N CP MAS NMR spectrum of 3 with that of 2 indicates that protonated morpholine is present in solid 3, but this conclusion must be taken with caution as GIPAW calculations predict a 15N chemical shift for morpholine similar to that of the morpholinium cation. Conclusive evidence for the presence of a morpholinium cation in crystalline 3 was obtained by recording the static 15N NMR spectrum of this host−guest complex and comparing the morpholinium/morpholine part of the spectrum with the static spectra of 3 and 4 as obtained from ab initio calculations of NMR parameters based on the X-ray structures of these compounds. Concerning the imidazolyl group,...

The low-temperature phase of morpholinium tetrafluoroborate

The crystal structure of the low-temperature form of the title compound, C4H10NO+·BF4 −, was determined at 80 K. Two reversible phase transitions, at 158/158 and 124/126 K (heating/cooling), were detected by differential scanning calorimetry for this compound, and the sequence of phase transitions was subsequently confirmed by single-crystal X-ray diffraction experiments. The asymmetric unit at 80 K consists of three BF4 − tetra­hedral anions and three morpholinium cations (Z′ = 3). Hydrogen-bonded morpholinium cations form chains along the [100] direction. The BF4 − anions are connected to these chains by N—H⋯F hydrogen bonds. In the crystal structure, two different layers perpendicular to the [001] direction can be distinguished, which differ in the geometry of the hydrogen bonds between cationic and anionic species.

Molecular Assemblies from Imidazolyl‐Containing Haloalkenes and Haloalkynes: Competition between Halogen and Hydrogen Bonding

The structural characterization of molecular assemblies constructed from imidazolyl-containing haloalkenes and haloalkynes is reported. 1-(3-Iodopropargyl)imidazole (2) and 1-(2,3,3-triiodoallyl)imidazole (5) were synthesized from 1-propargylimidazole (1). In the solid state, these wholly organic modules self-assemble through N...I halogen-bonding interactions, thus giving rise to polymeric chains. The N...I interaction observed in 2 (d(N...I)=2.717 A, angle-spherical C(sp)-I...N=175.8 degrees) is quite strong relative to previously reported data. The N...I interaction in 5 (d(N...I)=2.901 A, angle-spherical C(sp2)-I...N=173.6 degrees) is weaker, in accordance with the order C(sp)-X<--base>C(sp2)-X<--base. Compound 5 was found to give a 1:1 cocrystal 4 with morpholinium iodide (6). In the X-ray crystal studies of 4, N...I halogen-bonding interactions similar to those observed in 5 were shown not to be present, as the arrangement of the molecules is governed by two interwoven hydrogen-bonding networks. The first network involves N-H...O interactions between nearby morpholinium cations, and the second network is based on N-H...N hydrogen bonding between morpholinium cations and imidazolyl groups. Both hydrogen-bonding schemes are charge-assisted. Halogen bonding is not completely wiped out, however, as the triiodoalkene fragment forms a halogen bond with an iodide anion in its vicinity (d(I...I)=3.470 A, angle-spherical C(sp2)-I...I=170.7 degrees). X-ray crystal studies of 6 show a completely different arrangement from that observed in 4, namely, N-H...O interactions are not present. In crystalline 6, morpholinium cations are interconnected through C-H...O bridges (d(H...O)=2.521 and 2.676 A), and the NH2+ groups interact with nearby iodide anions (d(H...I)=2.633 and 2.698 A).

Thermal and electrochemical properties of ionic liquids based on N-methyl-N-alkyl morpholinium cations

A series of ionic liquids based on morpholinium cations were prepared. N-alkyl-N-methylmorpholinium bromide, N-alkyl-N-methylmorpholinium tetrafluoroborate, N-alkyl-N-methylmorpholinium hexafluorophosphate and N-alkyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide were synthesized, and then thermal and electrochemical properties of prepared ionic liquids were measured. These morpholinium salts were found to be thermally stable near 673 K and electrochemically stable up to 6 V at room temperature. In conclusion, these new series of morpholinium based ILs might be potential candidates for electrolytes in batteries and other electrolytic devices.

Morpholinium hydrogensulfate

The title compound, C4H10NO+·HSO4 −, contains a morpholinium cation and a hydrogensulfate anion, both placed on a mirror plane and with the anion disordered over two positions. Strong N—H...O hydrogen bonds play a dominant role in the crystal packing.

Bis(morpholinium) tetraiodo(morpholine-4-carbodithioato-κ2S,S′)bismuth(III)

The crystal structure of the title compound, (C4H10NO)2[Bi(C5H8NOS2)I4], the BiIII complex anions and morpholinium cations. The BiIII ion is coordinated by four I− anions and two S atoms from a morpholine-4-carbodithio­ate (mcda) dianion with a distorted octa­hedral coordination geometry. In the anion, Bi, the CS2 atoms, N, O and two I atoms are located on a mirror plane; the morpholine C atoms of the mcda ligand are disordered on both sides of the mirror plane. N—H⋯I hydrogen bonding between the morpholinium cation and the BiIII complex stabilize the crystal structure.

Cyclic Quaternary Ammonium Ionic Liquids with Perfluoroalkyltrifluoroborates: Synthesis, Characterization, and Properties

New cyclic quaternary ammonium salts, composed of N-alkyl(alkyl ether)-N-methylpyrrolidinium, -oxazolidinium, -piperidinium, or -morpholinium cations (alkyl = nC4H9, alkyl ether = CH3OCH2, CH3OCH2CH2) and a perfluoroalkyltrifluoroborate anion ([R(F)BF3]-, R(F) = CF3, C2F5, nC3F7, nC4F9), were synthesized and characterized. Most of these salts are liquids at room temperature. The key properties of these salts--phase transitions, thermal stability, density, viscosity, conductivity, and electrochemical windows--were measured and compared to those of their corresponding [BF4]- and [(CF3SO2)2N]- salts. The structural effect on all the above properties was intensively studied in terms of the identity of the cation and anion, variation of the side chain in the cation (i.e., alkyl versus alkyl ether), and change in the length of the perfluoroalkyl group (R(F)) in the [R(F)BF3]- ion. The reduction of Li+ ions and reoxidation of Li metal took place in pure N-butyl-N-methylpyrrolidinium pentafluoroethyltrifluoroborate as the supporting electrolyte. Such comprehensive studies enhance the knowledge necessary to design and optimize ionic liquids for many applications, including electrolytes. Some of these new salts show desirable properties, including low melting points, high thermal stabilities, low viscosities, high conductivities, and wide electrochemical windows, and may thus be potential candidates for use as electrolytes in high-energy storage devices. In addition, many salts are ionic plastic crystals.

Two halide exchange in copper(II) halide dimers: (Morpholinium)2Cu2ClxBr6−x

Abstract The structural and magnetic properties of the planar Cu 2 Cl 6 - x Br x 2 - dimers in the (morpholinium)2Cu2Cl6 − xBrx salts are investigated. The Cu 2 Cl 6 2 - salt is triclinic, space group P 1 ¯ , a = 7.408(7), b = 10.458(10), c = 11.933(12) A, α = 82.26(2), β = 88.35(2), and γ = 77.22(2)° with Z = 2, while the Cu 2 Br 6 2 - salt is monoclinic, space group P21/c, a = 14.148(6), b = 10.814(4), c = 14.298(6) A and β = 117.108(7)° with Z = 4. The mixed halide salts are all isomorphous with the Cu 2 Br 6 2 - salt. Structurally, the compounds contain isolated dimeric species due to the weak coordination of the morpholinium cations to the copper ions via semi-coordinate Cu⋯O bonds. This is in contrast to other such dimer systems, where semi-coordinate Cu⋯X bonds link the dimers together into stacks or chains. In the morpholinium salts, hydrogen bonding ties the molecular units into a layered structure. These N–H⋯X hydrogen bonds force short X⋯X contacts between dimers with X⋯X distances of 3.92–4.07 A. In this manner, magnetic chains with alternating exchange pathways exist: the intradimer exchange coupling and the X⋯X (2H) pathway. Magnetic studies indicate that these systems behave as alternating AFM chains, demonstrating that the halide⋯halide contacts are effective exchange pathways. The magnetic studies show that the AFM coupling increases monotonically as the bromide content increases. The values for the Cu 2 Cl 6 2 - salt are J1/k = −41.6(1) K and J2/k = −26(2) K, while those of the Cu 2 Br 6 2 - salt are −149.5(5) and −59(2) K. Comparison with other systems suggests that J1 value for the chloride salt corresponds to the intradimer coupling while the J2 value is assigned to the two-halide pathway, while the assignments are reversed for the bromide containing salts.