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Interaction of solid KBH 4 with liquid Al(BH 4 ) 3 at room temperature yields a solid bimetallic borohydride KAl(BH 4 ) 4 . According to the synchrotron X-ray powder diffraction, its crystal structure (space group Fddd, a = 9.7405(3), b = 12.4500(4), and c = 14.6975(4) Å) contains a substantially distorted tetrahedral [Al(BH 4 ) 4 ]− anion, where the borohydride groups are coordinated to aluminum atoms via edges. The η -coordination of BH 4− is confirmed by the infrared and Raman spectroscopies. The title compound is the first aluminum-based borohydride complex not stabilized by halide anions or by bulky organic cations. It is not isostructural to bimetallic chlorides, where more regular tetrahedral AlCl 4 − anions are present. Instead, it is isomorphic to the LT phase of TbAsO 4 and can be also viewed as consisting of two interpenetrated dia-type nets where BH 4 ligand is bridging Al and K cations. Variable temperature X-ray powder diffraction, TGA, DSC, and TGA-MS data reveal a single step of decomposition at 160°C, with an evolution of hydrogen and some amount of diborane. Aluminum borohydride is not released in significant amounts; however, some crystalline KBH 4 forms upon decomposition. The higher decomposition temperature than in chloride-substituted Li−Al (70°C) and Na−Al (

Summary: Hydrophobically substituted diallylamines bearing a hexyl, dodecyl, or octadecyl chain were synthesized and homopolymerized as hydrochlorides. Copolymerization of the diallylamines with maleic acid produces alternating copolymers. The copolymers behave as amphiphilic polyampholytes and dissolve best in the acidic or in the basic form. Only the copolymer with the hexyl chain could be dissolved in aqueous solvents and shows hydrophobic association. The copolymers with the longer alkyl chains require polar protic organic solvents. All polymers are amorphous, but show a superstructure in bulk due to their amphiphilicity. magnified image