Supramolecular cations of the m-fluoroanilinium(dibenzo[18]crown-6) in ferromagnetic salt.
A supramolecular cation of (m-FAni(+))(DB[18]crown-6), where m-FAni(+) and DB[18]crown-6 denote m-fluoroanilinium(+) and dibenzo[18]crown-6, respectively, which is the polar unit rotating in the ferroelectric crystal of (m-FAni(+))(DB[18]crown-6)[Ni(dmit)(2)](-), was introduced into a ferromagnetic [MnCr(oxalate)(3)](-) salt as the counter cation. The crystal structure of (m-FAni(+))(DB[18]crown-6)[MnCr(oxalate)(3)](-)(CH(3)OH)(CH(3)CN) (1) is constructed from alternating layers of a two-dimensional honeycomb layer of [MnCr(oxalate)(3)](-) and (m-FAni(+))(DB[18]crown-6) supramolecular cations. The anionic layer is composed of Mn(II) and Cr(III) ions with S = 5/2 and S = 3/2 spins, respectively, bridged by the oxalate anions, which show ferromagnetic ordering at 5.5 K. The supramolecular structure is formed through the formation of hydrogen bonds between the ammonium hydrogen atoms of the m-FAni(+) cations and the oxygen atoms of the DB[18]crown-6 cavity. No orientational disorder of the fluorine atoms was observed in our X-ray structural analysis, suggesting that a two-fold flip-flop motion of the m-FAni(+) cations does not occur in the salt. The rotational freedom of the m-FAni(+) cations in the salt is restricted by the steric hindrance from neighbouring DB[18]crown-6 molecules. A design strategy for the rotation in a salt is discussed, based on the volume that the supramolecular cations occupy in the unit cell.
Hokkaido University, Sapporo, Japan.
Toru
T
Endo
Tomoyuki
T
Akutagawa
Shin-ichiro
S
Noro
Takayoshi
T
Nakamura
D000814:Aniline Compounds / Q000737:chemistry*; D002412:Cations / Q000138:chemical synthesis / Q000737:chemistry; D043844:Crown Ethers / Q000737:chemistry*; D018360:Crystallography, X-Ray; D046911:Macromolecular Substances / Q000138:chemical synthesis / Q000737:chemistry; D008280:Magnetics; D008958:Models, Molecular; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D012492:Salts / Q000138:chemical synthesis / Q000737:chemistry
D000814:Aniline Compounds; D002412:Cations; D043844:Crown Ethers; D046911:Macromolecular Substances; D009942:Organometallic Compounds; D012492:Salts; C002564:dibenzo-18-crown-6; C023650:aniline