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New azametallatranes of the type Me&(RNCH2CH2)3N, where R = i-Pr, M = Ti (16), Zr (17), and Hf (18); R = SiMe3, M = Ti (19), Zr (20), and Hf (21); and R = SiMez(t-Bu), M = Zr (23) and Hf (24), were prepared I by metathesis reactions in moderate to high yield. During the course of the preparation of 19, Me&OTi(Me3-SiNCH2CH2)3N, 25, was formed in trace amounts. The latter compound was also synthesized by a metathesis reaction in a quantitative yield. Compounds 21 and 25 were structurally characterized and both were shown to exhibit a distorted trigonal bi yramidal metal center. Crystal data: 21, orthorhombic, space group P212121, a = 11.837(2) A, b = 14.284(3) 1, c = 15.750(4) A, V = 2662.9(9) A3, Z = 4, R = 0.0352; 25, orthorhombic, space group Pna21, a = 21.772(2) A, b = 11.481(4) A, c = 11.566(1) A, V = 2891(1) A3, Z = 4, R = 0.0341.

The relative rates of displacement of the NR2 group in (dialkylamido)titanatranes R2NTi(OCH2CH2)3N by -OH and -SH compounds is in the order NEt2 » NMe2 > N(/-Pr)2. This unanticipated order is rationalized on the i i postulated prior formation of HR2N+Ti(OCH2CH2)3N (A), which facilitates departure of R2NH upon subsequent nucleophilic attack. For R = Et and /-Pr, the concentration of A is higher than for R = Me, owing to the basicity order Et2N s (i-Pr)2N > Me2N. The greater reactivity of A where R = Me relative to R = /-Pr is attributed to the greater steric protection from nucleophilic attack on the metal afforded by the H(/-Pr)2N+ group. The faster reactions of CF3CH2OH and PhOH compared with their sterically similar but more weakly acidic analogues CH3CH2OH and /-PrOH, respectively, support this hypothesis as do the comparable displacement rates of Et2N and Me2N in the presence of the strong nonnucleophilic base P(MeNCH2CH2)3N and the reactions of 4 and 14 with HBF4 and NH4C1 but not with NaBF4 or Me4NCl. New titanatranyl derivatives reported include five arylates, i-1 two thioarylates, and four diolates. The X-ray parameters for [/-PrSTi(OCH2CH2)3N]2 are as follows: triclinic, space group Pi (No. 2), a = 7.434(5) A, b = 12.540

The syntheses of the perchlorate salts of H(TEA)+ (l), Li(TEA)+ (2), Na(TEA)+ (3), Sr(TEA)22+ (4), and Ba-(TEA)22+ (5), wherein TEA = triethanolamine, are reported. Characterizational NMR spectral results ('H, 13C, 'Li, 23Na) as well as crystal structures for 1,3, and 5 are discussed. The structures of 1,3, and 5 reveal respectively thecation H(TEA)+ in which the proton is in a tetrahedral environment, a seven-coordinate sodium weakly coordinated by a monodentate C104-and two OH oxygens from neighboring units, and a [Ba(TEA)C104]22+ cation in which two weakly coordinating perchlorates bridge two Ba2+ ions in a bidentate fashion. Extensive hydrogen bridging via C104-ions occurs in all three compounds giving rise to parallel sheet structures. Crystal data: 1 (at 22 "C), a = 9.086(1) A and c = 23.919(6) A, with 2 = 6 in space group R3c; 3 (at 20 "C), a = 9.617(1) A, b = 7.787(1) A, c = 15.914(2) A, and B = 105.80°, with 2 = 4 in space group P2,/c; 5 (at -50 "C), a = 7.498(2) A, b = 10.492(2) A, c = 15.749(3) A, a = 76.06(2)", 0 = 80.56(2)", and y = 76.70(2)", with 2 = 2 in space group Pi.