NOVEL STRUCTURAL ARRANGEMENT FOR DIVALENT METAL PHOSPHONATES - SYNTHESIS OF TERT-BUTYLPHOSPHONATES AND STRUCTURE OF CO[(CH3)3CPO3].H2O

The synthesis and characterization of new divalent metal tert-butylpho sphonates are described: M(II)[(CH3)3CPO3].xH2O [M(II)=Co, Mn (x=1); M (II)=Zn (x=2/3)] and Cu1.75O0.75[(CH3)3CPO3].H2O . Co[(CH3)3CPO3].H2O crystallizes in the monoclinic space group P2(1)/c with a=12.256(1) an gstrom, b=17.939(1) angstrom, c=10.769(1) angstrom, beta=93.57(1)-degr ees, V=2363.1(4) angstrom3, Z=12, with R=0.064 and R(w)=0.075 for 1805 observed reflections, according to the criterion 1>3sigma(I). The lay er arrangement of this new phase is different from that observed in th e case of the n-alkyl M(II)(RPO3).H2O analogues owing to the steric ef fect of the bulky tert-butyl group. The structural relationship betwee n the cobalt, manganese and zinc compounds is discussed. The observed magnetic moments are consistent with the presence of high-spin Mn(II) or Co(II) and with the existence of both octahedral and tetrahedral en vironments about these metals.