The reaction of alkali metal acetates, M(OAc). nH(2)O (M = Li, Na, K), with thermally and hydrolytically unstable di-tert-butylphosphate (((BuO)-Bu-t)(2)PO2H, dtbp-H) in a 1:1 molar ratio in MeOH at room temperature leads to clean formation of group 1 metal phosphates Li(mu-dtbp)(n) (1), Na(mu-dtbp)(n) (2), and K-4(mu-dtbp)(4)(mu-H2O)(3)(n) (3). All three compounds are essentially M/L 1:1 complexes. Owing to the presence of larger potassium ions, additional coordinated water molecules are found in 3, which has been further employed as a precursor for the synthesis of a mixed-metal phosphate polymer CaK(mu-H2O)(3)(mu-dtbp)(3)(n) (4) by reacting 3 with Ca(OAc)(2). Compounds 1-4 have been characterized by various analytical and spectroscopic techniques. Molecular structures of 1-4 have been established in the solid state by single-crystal X-ray diffraction studies, which reveal them to be one-dimensional polymers, where the adjacent metal centers are connected through -O-P-O- bridges formed by the dtbp ligand. These complexes are rare examples of analytically pure alkali metal alkyl phosphates bearing no additional Ndonor ligands (other than dtbp ligands, only water molecules are coordinated to the metal centers). Therefore, these compounds can be employed as single-source precursors (SSPs) for nano-sized ceramic phosphates. The thermogravimetric analysis of 1-4 reveals the loss of thermally labile tert-butyl substituents of the organophosphate ligands to form organic-free phosphate materials in the temperature range 300-500 degrees C. Solvothermal decomposition of 1-3 in boiling toluene leads to the formation of corresponding dihydrogen phosphates M(H2PO4) (M = Li, Na, and K). The thermal decomposition of heterometallic 4 in the temperature range 400-800 degrees C leads to the formation of phase-pure mixed-metal calcium potassium metaphosphate CaK(PO3)(3).
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