Covalent metal-organic networks: Pyridines induce 2-dimensional oligomerization of (mu-OC6H4O)(2)Mpy(2) (M = Ti, V, Zr)

Treatment of M((OPr)-Pr-i)(4) (M = Ti, V) and [Zr(OEt)(4)](4) With excess 1 ,4-HOC6H4OH in THF afforded [M(OC6H4O)(a)(OC6H4OH)(3.34-1.83a)((OPr)-Pr-i)( 0.66-0.17a)(THF)(0.2)](n) (M = Ti, 1-Ti; VI 1-V, 0.91 less than or equal to a less than or equal to 1.82) and [Zr-(1,4-OC6H4O)(2-x)(OEt)(2x)](n) (1-Zr , x = 0.9). The combination of of 1-M (M = Ti, V, Zr) or M((OPr)-Pr-i)(4) ( M = Ti, V), excess 1,4- or 1,3-HOC6H4OH, and pyridine or 4-phenylpyridine a t 100 degreesC for 1 d to 2 weeks afforded various 2-dimensional covalent m etal-organic networks: [cis-M(mu (1,4)-OC6H4O)(2)py(2)](infinity) (2-M, M = Ti, Zr), [trans-M(mu (1,4)-OC6H4O)(2)py(2). py](infinity) (3-M, M = Ti, V) , solid solutions [trans-TixV1-x(mu (1,4)-OC6H4O)(2)py(2). py](infinity) (3 -TixV(1-x), x approximate to 0.4, 0.6, 0.9), [trans-M(mu (1,4)-OC6H4O)(2)(4 -Ph-py)(2)](infinity) (4-M, M = Ti, V), [trans-Ti(mu (1,3)-OC(6)H(4)O(2)py( 2)](infinity) (5-Ti), and [trans-Ti(mu (1,3)-OC6H4O)(2)(4-Ph-py)(2)](infini ty) (6-Ti) Single-crystal X-ray diffraction experiments confirmed the pleat ed sheet structure of 2-Ti, the flat sheet structure of 3-Ti, and the rippl ed sheet structures of 4-Ti, 5-Ti, and 6-Ti. Through protolytic quenching s tudies and by correspondence of powder XRD patterns with known titanium spe cies, the remaining complexes were structurally assigned. With py or 4-Ph-p y present, aggregation of titanium centers is disrupted, relegating the bui lding block to the cis- or trans-(ArO)(4)Tipy(2) core. The sheet structure types are determined by the size of the metal and the interpenetration of t he layers, which occurs primarily through the pyridine residues and inhibit s intercalation chemistry.