Ligand design for functional metal-organic frameworks.

Metal-organic frameworks (MOFs), also known as coordination polymers, are formed by the self-assembly of metallic centres and bridging organic linkers. In this critical review, we review the key advances in the field and discuss the relationship between the nature and structure of specifically designed organic linkers and the properties of the products. Practical examples demonstrate that the physical and chemical properties of the linkers play a decisive role in the properties of novel functional MOFs.

Chemistry and catalytic activity of molybdenum(VI)-pyrazolylpyridine complexes in olefin epoxidation. Crystal structures of monomeric dioxo, dioxo-μ-oxo, and oxodiperoxo derivatives.

The dioxomolybdenum(VI) complexes [MoO2Cl2(PzPy)] (1) and [MoO2(OSiPh3)2(PzPy)] (5) (PzPy = 2-[3(5)-pyrazolyl]pyridine) were synthesized and characterized by vibrational spectroscopy, with assignments being supported by DFT calculations. Complex 5 was additionally characterized by single crystal X-ray diffraction. Recrystallization of 1 under different conditions originated crystal structures containing either the mononuclear [MoO2Cl2(PzPy)] complex co-crystallized with 2-[3(5)-pyrazolyl]pyridinium chloride, binuclear [Mo2O4(μ2-O)Cl2(PzPy)2] complexes, or the oxodiperoxomolybdenum(VI) complex [MoO(O2)2Cl(PzPyH)], in which a 2-[3(5)-pyrazolyl]pyridinium cation weakly interacts with the Mo(VI) center via a pyrazolyl N-atom.

Microwave-assisted synthesis of metal-organic frameworks.

Microwave heating, used in organic chemistry for several decades, has only recently been applied to the preparation of multi-dimensional coordination polymers, more commonly known as metal-organic frameworks (MOFs). Microwave heating allows short reaction times, fast kinetics of crystal nucleation and growth, and high yields of desirable products which can be isolated with few or no secondary products. The most significant developments in the use of microwave heating for the preparation of MOFs are briefly reviewed from this perspective, emphasizing systematic studies of well-characterised materials, which lead to their isolation in large quantities over economically-viable periods of time.

Oxidation of volatile organic compounds on SBA-15 mesoporous molecular sieves modified with manganese.

Catalytic combustion of volatile organic compounds, such as propene, has been studied on manganese modified mesoporous molecular sieves. Powder X-ray diffraction, (29)Si nuclear magnetic resonance, nitrogen sorption and transmission electron microscopy show that the SBA-15 mesoporous silica molecular sieve can be modified with manganese using Mn(2)(CO)(10) or Mn(O(2)CMe)(2) without significant distortion of the host structure. The two products were catalytically active in propene oxidation, with SBA-15 modified with Mn(2)(CO)(10) showing significantly higher activity, possibly due to higher Mn content, than SBA-15 modified with Mn(O(2)CMe)(2).

Poly[[aqua-μ(3)-picolinato-μ(2)-picolinato-dipicolinatopotassium(I)terbium(III)] 2.5-hydrate].

In the title compound, [KTb(C(6)H(4)NO(2))(4)(H(2)O)]·2.5H(2)O, each Tb(3+) centre is coordinated by four N and five O atoms from five distinct picolinate ligands in a geometry resembling a highly distorted tricapped trigonal prism. One of the ligands establishes a skew bridge between neighbouring Tb(3+) centres, leading to the formation of one-dimensional anionic polymeric chains, {[(C(6)H(4)NO(2))(4)Tb](-)}(n), running along the direction [010].