SYNTHESIS, CHARACTERIZATION, AND REACTIVITY OF MONOMERIC STRONTIUM AND BARIUM TRIPHENYLSILOXIDE COMPOUNDS - MOLECULAR-STRUCTURE AND REACTIVITY OF M(OSIPH(3))(2)(15-CROWN-5)THF, M=SR(1) AND BA(2)

The reaction of Sr with Ba and 15-crown-5 and HOSiPh(3) in THF in the presence of NH3, results in formation of the species M(OSiPh(3))(2)(15 -crown-5)THF, M = Sr 1 and Ba 2. These species were shown to be among the first examples of monomeric Group 2 siloxide compounds in the soli d state by single-crystal X-ray diffraction. Thermally induced reactio n in the solid state resulted in loss of the organic supporting ligand s by similar to 250 degrees C with formation of MSi(2)O(5), whereas in refluxing toluene, (1) and (2) underwent silyl ether elimination ((Ph (3)Si)(2)O). The reaction of (2) with Ti(O-i-Pr)(4) in toluene solutio n at 60 degrees C resulted in elimination of Ph(3)Si-O-i-Pr.