Synthesies, Structures And Properties Of Isoquinolines Compound Quarternary Ammonium Salts

Inorganic metal complex anions such as bis(maleonitriledithiolate)nickel(III)([Ni(mnt)2]–), bis(maleonitriledithiolate)cuprate(II)([Cu(mnt)2]2–) and organic acid radical anion picrate([PIC]–) are the useful molecular building unit in the molecular magnets and molecular solids.Fifteen new quarternary ammonium salts, [2Cl BzIQl][Ni(mnt)2](1),[2Br Bz IQl][Ni(mnt)2](2), [2IBz IQl][Ni(mnt)2](3), [2NO2Bz IQl][Ni(mnt)2](4), [4FBz IQl][Ni(mnt)2](5), [4CNBz IQl][Ni(mnt)2](6), [Bz IQl]2[Cu(mnt)2](7), [2Cl Bz IQl]2[Cu(mnt)2](8), [2NO2Bz IQl]2[Cu(mnt)2](9), [3Cl Bz IQl]2[Cu(mnt)2](10), [3NO2Bz IQl]2[Cu(mnt)2](11), [4Cl Bz IQl]2[Cu(mnt)2](12), [4NO2Bz IQl]2[Cu(mnt)2](13), [Bz IQl][PIC](14), [4NO2Bz IQl][PIC](15) were obtained by introducing substituted benzyl isoquinolinium cations into the system of the inorganic complex and organic acid radical anions described above. These salts were characterized by IR, UV-Vis spectra and X-ray single crystal diffraction. In addition, the magnetic properties of 1~13 and the fluorescent properties of 14~15 have been studied, and the relationship between the crystal structures and properties was investigated primarily.1. In the quarternary ammonium salts 1~6, the proportion of anion and cation in an asymmetric unit, crystal system and space group are different due to the different substituted groups and substituted position. The quarternary ammonium salts 1 and 2crystallized in monoclinic system with P21/c space group, and 3, 5 and 6 belonged to triclinic system with P-1 space group while 4 crystallized in monoclinic system with C2/c space group. The crystal cell parameters of the quarternary ammonium salts 1 and 2 are similar and different from other four. The asymmetric unit cell of quarternary ammonium salts 1, 2, 5 and 6 comprised one [Ni(mnt)2]– anion and one [RBz IQl]+ cation, while an acetonitrile molecule were found in 4, and two pairs of [Ni(mnt)2]– anions and [RBz IQl]+cations and an acetonitrile molecule in 3. It's noted that the anions formed a 1D alternating magnetic chain in the quarternary ammonium salts 1~6, while the anionic overlapping mode are different. Due to different substituented group and substituented position in the benzene ring, dihedral anglles between reference plane and benzene ring in cation were changed, which resulted in a significant change about spatial arrangement and stacking manners anions and cations: the anionic dimer are formed salts 1 and 2, and are connected with two anions through CN···? weak interactions, while the cationic tetramer is connected with anionic dimer through S···? weak interactions in 3, as the same time, the neighboring cations formed a 1D chain structure in 4 and 5, and formed a ···A-C-A-C···sequenced between the anions and cations through ? ×× ×? interactions in 5, but the adjacent cations formed 2D sheet structure, and the anionic sheet with cationic sheet alternate arrangement through C–H···N hydrogen bonds in 6. Accordingly, these analyzed different changes above in the crystal structures resulted in the difference of magnetic properties. The salts 1 and4~6 exhibited typical magnetic behavior of a spin gap system, 4 and 6 spin transition temperatures were 45.9 and 167.7 K, respectively; 5 exhibits the magnetic behavior of the spin gap system around 7.5 and 103.8 K, respectively; while 3 around 7, 50 and 270 K,respectively. Besides 2 and 3 showed strong antiferromagnetic coupling interaction by the dinuclear model formula with J = – 676.0 and –507.0 cm–1, respectively.2. In quarternary ammonium salts 7 and 9~11, the asymmetric unit are composed of one cation and half a anion, while 8, 12 and 13 containing of two cations and one anion,and 7, 11~13 belong to triclinic system with P-1 space group, while 8~10 did in monoclinic system with P21/c space group for 8 and 9, and C2/c space group for 10. The anions and caions formed a ···A-CC-A-CC···sequenced stack chain through different weak interactions in 7~13 beside 9. The neighboring cations formed a regular 1D chain stucture for 7, 8 and10, tetramer for 9; the neighboring anions formed a 1D chain stucture through C···N weak interactions in 10; anionic sheet and cations sheet formed in 11, and anionic dimer and cationic dimer formed in 12 and 13. The ortho-position nearest Cu × × × Cu distance are smallest when the H stom in benzene ring are changed Cl or NO2 group. The magnetic susceptibility data can be finely fitted to the Curie–Weiss law with the Weiss constant of0.433 K(7), 0.810 K(8), 0.019 K(9),-0.318(10),-13.48 K(11),2.428 K(12) and 1.50 K(13),in which 9 and 11 are very weak ferromagnetic exchange, while others show the change from ferromagnetic to antiferromagnetic coupling interaction.3. Quarternary ammonium salts 14 and 15 crystallized in monoclinic system, but the space groups were different, quarternary phosphinium salt 11 crystallized in C2/c space group while salts 12 Cc space group. The asymmetric unit of 14 consists of one cation and one anion, while 15 include two cations and two anions. Two adjacent anions formed anionc dime for 14 and 15, and adjacent anionic dimers formed a chain structure for 15. As the same time, the neighboring cations formed a chain structure in 14 and 15, and the adjacent cations and anions formed a ···AA-CC-AA-CC··· chain stack structure through C–H···O hydrogen bonds. Differential thermal analysis(DTA) carried out on the grown crystal indicates that salts 14 and 15 does not sublime before they melts at 181.90 °C and183.28 °C, respectively, and takes place in three stage weight loss. As the same time, 14 and 15 show three main emission peaks about 387, 538 and 768 nm upon the same max excitation in solid state at room temperature, but the second emission band for 15 is wider than that in 14. Due to the H atom in benzene ring is substituted NO2 group, so the structures and weak interactions are changed in quarternary ammonium salts, and the fluorescence properties are also changed.