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Metal-organic frameworks (MOFs) are crystalline materials that are composed of an infinite array of metal nodes (single ions or clusters) linked to one another by polyfunctional organic compounds. Because of their extraordinary surface areas and high degree of control over the physical and chemical properties, these materials have received much attention in the recent literature for industrial applications, such as gas storage. As the applications of MOFs are significant, the underlying concepts for their design and synthesis may be used in the upper-level undergraduate laboratory as a vehicle for promoting student understanding of a wide variety of chemical concepts. These include targeted synthesis, crystallography, and adsorption theory of gases. This laboratory experiment involves the synthesis and full characterization of three MOFs that are derived from inexpensive materials, followed by surface area calculations, and in the case of one material, postsynthetic modification. Owing to the high focus on solid-state characterization, we believe this course will also provide students with a foundation in characterization methods they would not normally encounter in a typical inorganic chemistry laboratory course. (Contains 2 figures and 1 scheme.)

Research has been conducted on the titanium dinitrigen complex. The synthesis of this complex has been carried out via the dichloride precursor reduction and the solid-state and solution structures of the complex are discussed.

Research has been conducted on the nu (super)2 -amides. The utility of these amides as supporting ligands for the early transition metals has been investigated, and the synthesis of the linked bis-amidate ligand and the titanium complexes supported by this ligand system is reported.

Homoleptic selenolates of V(II) and V(IV) were produced by selenolysis of the amide ligands in ((Me3Si)2N)2VSeSi(SiMe3)3 with 2 equiv of HSeSi(SiMe3)3. These compounds were suggested to be the disproportionates of a V(III) precursor. Room temperature electron paramagnetic resonance spectra of the tetraselenolate showed an eight-line pattern typical of V(IV). Addition of 2 equiv of DMPE (DMPE = 1,2-bis(dimethylphosphino)ethane) to the V(II) selenolate produced trans-(DMPE)2V(SeSi(SiMe3)3)2.

Three coordinate bis(bistrimethylsilylamido)vanadium(III) chalcogenolates were produced by the salt methatesis reaction of [(Me3Si)2N]2V(Br)(THF) and (THF)2LiESi(SiMe3)3 (E= Se, Te) or (THF)xLiESiPh3 (E = Se, Te). The paramagnetic bis(amido)vanadium(III) silyl selenolates and tellurolates exhibit solid state magnetic moments that range from 2.45-2.65 muBM. The compounds have similar geometrical parameters with different crystal packing.

The salt metathesis or chalcogenolysis of metal chalcogenolates generates group 4 homoleptic tris(trimethylsilyl)silyl selenolates and tellurolates. Salt metathesis between MCl4 (M = Zr, Hf) and (tetrahydrofuran)2LiSeSi(SiMe3)3, or chalcogenolysis reaction between M(CH2Ph)4 and HESi(SiMe3)3 (E = Se, Te) generate M(ESi(SiMe3)3)4. The X-ray crystal structures of M(ESi(SiMe3)3)4 and M(SeSi(SiMe3)3)3- (CH2Ph) (M = Ti, Zr, Hf; E = Se, Te) are determined. The tellurolate ligand readily reacts with Lewis bases, despite steric shielding. The synthesis of 1,2-bis(dimethylphosphino)ethane adducts is discussed.

The preparation of a range chalcogenolate complexes of group 13 and 15 derivatives accommodating sterically hindered alkane and silaneselenolate and silanetellurolate ligands are discussed. Reactions of these complexes with various heavier metal compounds are also explored. Crystallographic data are provided for the compounds formed with Ga, In and P.

Syntheses of calcium, strontium, magnesium and barium selenolates and tellurolates involve the use of sterically encumbered silyl ligands -ESi(SiMe3)3. NMR experiments help characterize these complexes in solution, and magnesium selenolate exists as a stereochemically nonrigid dimer in solution. X-ray crystallographic studies enable the determination of the structures of selenolate and tellurolate derivatives.

A new modified existing procedure helps synthesize new lithium porphyrin derivatives Li2(P)(ether)2 (P = tetra-p-tolylporphyrin (TTP), tetrakis-(p-tert-butylphenyl)porphyrin). These derivatives are soluble in nonpolar solvents and have a well-defined stoichiometry. Variable-temperature multinuclear NMR spectroscopic studies help determine the solution structure of Li2(TTP)(Et2O)2. A new improved method helps synthesize 3,4-diethylpyrrole.

Selenolate and tellurolate ligands are developed using bulky silyl substituent -Si(SiMe3)(3). These ligands are used for the synthesis of complexes of increased hydrocarbon solubility and low molecularity, involving main group and transition metal atom. Monomeric divalent lanthanide complexes are prepared by a protonolysis reaction and the yield is 53-72%. X-ray crystallography is used to study the structure.

A selenolate derivative reacts with CuCl or AgNo3 to form homoleptic copper(I) and silver(I) selenolates and the yield is 50%. X-ray crystallographic studies show that silver selenolates is a tetramer packed in the unit cell with van der Waals contacts between methyl groups. Molecular structure of copper selenolate is proved as dimer packed in a unit cell with van der Waals contacts between molecules.

Tellurolysis of a hexane solution of Mn(N(SiMe3)2)2 with two equivalents of HTeSi(SiMe)3, followed by Lewis donor addition and crystallization, yields first order, four-coordinate mono-dmpe Mn adducts. H NMR spectroscopic studies reveal broad-TeSi(SiMe3)3, dmpe and tert-7-butylpyridine signals at delta 4.7, 2.5 and 2.5 parts per million, respectively. Metathesis of Fe(II) Cr(II) and Co(II) metal tellurolates using the Mx2(dmpe)2 adduct yields the respective tellurolate derivatives. The Mn derivative crystal has two independent chiral pair molecules.

Homoleptic gold(I) chalcogenates with the general formula Au(ER), where E = S, Se or Te and R = C(Si(Me3)3, Si(SiMe3) or Ge(SiMe3)3), were synthesized by the reaction between AuCl(THT), a lithium salt, and triphenyl phosphine. LiER and Ph3PAuCl undergo metathesis in diethyl ether solution to form Ph3PAi(ER).

An experiment was conducted to develop and define homoleptic tin(II) and lead(II) tellurolates, selenolates and thiolates, which possess ESi(SiMe3)3 ligands. Elementary examination and x-ray powder diffraction corroborated the structure and crystallinity of these complexes. Due to thermolysis, UV irradiation or combination of Lewis bases with hydrocarbon solutions related decomposition reactions may occur at low temperatures.

An analysis of a series of chalcogenolate species (sol)n LiEY (SiMe3)3 by direct insertion of elemental E into Li-Y bonds of (THF)3 LiC(SiMe3)3, (THF)3LiSi(SiMe3)3, or (THF)3LiGe(SiMe3)3 indicated that two derivatives, (THF)2LiSeSi(SiMe3)3 and (THF)-LiSSi(SiMe3)3 are easily synthesized by chalcogen metathesis reaction. Tellurium is displaced from (THF)2LiSeSi(SiMe3)3 by either Se or S in THF at -55 degrees centigrade. Protonation of the chalcogenolate anions gives stable chalcogenols, HEY(SiMe3)3. The X-ray structure of the mono-THF adduct (THF)LiTeSi(SiMe3)3 synthesized from (THF)LiN(SiMe3)2 and HTeSi(SiMe3)3 crystallizes in the triclinic space group P1.

The preparation and characterization of dilithium salts and related tetraaryl derivatives are discussed and a detailed structural characterization of porphyrin complexes is presented. The TMPP complex had a square-planar lithium ion at the center of the porphyrin ring while the (Li(TMPP))- anion was centrosymmetric and very planar, with porphyrin groups inclined approximately perpendicular to the porphyrin ring. The sodium derivative existed as a discrete molecule in the solid state, also centrosymmetric with six-coordinate soium ions bound to the four nitrogen atoms.

A class of silyl tellurolate complexes of the -TeSi(SiMe3)3 anion was synthesized and characterized. The thermally stable lithium tellurolate derivative (THF2LiTeSi(SiMe3)3)2 was generated from the insertion of THF into (THF)3LiSi(SiMe3)3. X-ray crystallography revealed the molecule and its Li2Te2 core to be dimeric, with no interactions between dimeric units. The reaction of the compound with Et4NClin diethyl ether yielded (Et4N)(TeSi(SiMe3)3), while its treatment with triflicacid in hexane gave HTeSi(SiMe3)3.

The synthesis and characterization of low-coordinate homoleptic zinc, cadmium and mercury sitel derivatives were investigated. Synthesis of the homoleptic tellurolates proceeded from the tellurolysis reaction between HTeSi(SiMe3)3 and group 12 amides in nonpolar hydrocarbons. (Zn TeSi SiMe3 3 2)2 cruystallizes in the space group P1, with an inversion symmetry between the two asymmetric units. The pyridine adduct Zn(TeSi SiMe3 3)2(pyr)2 formed from zinc tellurolate and pyridine crystallizes in the space group P1 with a distorted tetrahedron geometry around the zinc center.

Homoleptic tellurolates of zirconium and hafnium were prepared from -TeSi(SiMe3)3 ligand by tellurolysis of several metal tetraalkyls. X-ray crystal analysis of zirconium tellurolates showed the structure to consist of evenly-spaced molecules with the zirconium and four tellurium atoms in a pseudotetrahedral coordination environment. The reactivity of the compounds were investigated by reacting with a series of Lewis bases.

The reaction of [(CpSi[Me.sub.3]).sub.3]U or [(CpSi[Me.sub.3]).sub.3]Nd with [(Cp*Al).sub.4] or Cp*Ga (Cp* = [C.sub.5][Me.sub.5]) has produced the isostructural complexes [(CpSi[Me.sub.3]).sub.3]M-ECp* (M = U, E = Al; M = U, E = Ga; M = Nd, E = Al; M = Nd, E = Ga) and their structures are characterized. The computational bonding analyses have shown that Cp*Al and Cp*Ga has behaved as good [sigma]-donors in these systems.

The carbonylation reaction of the dimethylniobium complex (BDI)[Me.sub.2]Nb([N.sup.t]Bu) (BDI = [beta]-diketiminate) is described. The results have shown an ability to dial in specific product mixture based on very subtle modifications to the reaction conditions, however the close proximity of diverse reaction pathways for second-row transition metals have impeded the progress in these areas.

The synthesis and characterization of the first example of a complex with an unsupported lanthanide-metal bond between an actinide and group 13 element is reported. The complexes are found to be stable in solution and the results from density functional theory revealed that the U-Al bond exhibited covalent character due to charge transfer from the Cp*Al ligand onto uranium.

The syntheses and characterization of many octahedral hexatantalum cluster compounds are described. The optical properties and oxidation/reduction properties have shown that the compounds possess an electronic structure wherein the highest occupied molecular orbitals are ligand centered, while the lowest unoccupied orbitals are metal-centered and delocalized throughout the tantalum cage.

Metal-halide complexes of multidentate monoanionic ligand with first row transition metals are studied using x-ray crystallography. The flexible nature of the [[N.sub.2][P.sub.2]] ligand allows it to bind to the metals as either tridentate or a tetra dentate ligand.

The syntheses, coordination chemistry and reactivity of a series of main group, transition metal, and actinide metal complexes supported by bis(2-picolyl)(2-hydroxy-3,5-di-tert-butylbenzyl)amide, H(BPPA) are reported.

The first homogeneous acid catalyst that promotes both hydroamination and hydroarylation reactions of anilines and alkenes, including simple cyclic alkenes and dienes is reported. These transformations are air- and moisture-tolerant and could be controlled to favor either N-H or Ar-H addition products based on reaction conditions and aniline substitution pattern.

A simple method for obtaining a multifunctional material using procedures based on Atom Transfer Radical Polymerization (ATRP) by growing polymers directly on silicon/silica core/shell nanowires is described. This method can be extended to other polymers and other inorganic templates to realize a wide range of hybrid materials with controllable surface chemistry.

A short Ti-Fe interaction in a diamide is observed during the stabilization of a cationic Ti center by a ferrocene moiety.

Research investigating the developments of ancillary ligands in catalytic reactivity is presented, with focus on the lithium-tantalum alkylidene. Particular attention is given to the support provided by the ligand anionic traizacyclononane.

Reactivity studies of compounds containing multiple bonds between early transition metals and the lighter group 16 elements (O and S) was probed. It was found that the Ti(sub 2)N(sub 2) linkage was relatively stable retainng its structural configuration despite the refluxing presence of toluene. H NMR spectroscopy revealed the addition of dry O2 to (L2Ti)2(mu N2) resulted in a 1,3-silyl migration to form a nano-NC-(Ph)N (SiMe3)2 ligand. The intermediacy of a terminal sulfido species was confirmed following generation of the bridging sulfido by sulfur atom abstraction with Hg.

A new class of amidinate derivatives containing redox-active centers that can be employed in the preparation of metal-containing polymers, polymetallic complexes and electrochemically controlled catalysts were synthesized and characterized. Incorporation of the ferrocenyl group was investigated because of its well-established chemistry, its high stability and the facility with which simple derivatives can be prepared.

A low-temperature route for the preparation of cis-Zr(por)Cl2 is described. The method is used to prepare novel cis-Sn(Por)Ph2 isomers whose stereochemistry is controlled by the choice of synthetic method, rather than by the nature of the central metal ion. The isomers are unusual because they have accessible and stable cis and trans metalloporphyrin geometries.

The synthesis and characterization of novel N,N'-bis(trimethylsilyl)benzamidinate ligand system are described. The complex has been formed by the reduction of PhC(NSiMe3)2 (sub 2)TiCl2 with 1% Na/Hg in toluene under N2, followed by crystallization from hexanes. X-ray crystallographic analysis showed a five-coordinate titanium and the end-on bonding mode of the bridging N2. The complex showed unusual reactivity such as the cyclometalation of N,N,N',N'-tetramethylethylenediamine and the cleavage of an amidinate ligand.

A simple metathesis reaction uses dilithium porphyrin reagents to prepare various Ta(V) porphyrin derivatives, including the sandwich compound (Ta(OEP)2)-(TaCl6) and the first organometallic tantalum metalloporphyrin A. X-ray studies of (Ta(OEP)2)(TaCl6) reveals that each Ta(OEP)(sub 2)(super +) group has crystallographic symmetry, with single pyrrole ring PerOEP and four TaCl(sub 6)(super -) anions surrounding each cation. The electronic spectrum of the complex suggests stronger interaction of porphyrin rings in Ta complex and Ta(OEP)Cl3 undergoes hydrolysis forming a tris mu-oxo binuclear complex.

The thermal decomposition of lanthanide tellurolates into bulk metal tellurides was studied. Reactive homoleptic lanthanide(III) tellurolates were decomposed in the absence of stabilizing donor ligands to form novel molecular telluride-tellurolate clusters. The NMR spectrum of the lanthanum derivatives were then analyzed. Results that extensive pyrolysis leads to the formation of bulk metal tellurides.

The synthesis and characterization of group two tellurolates based from the -TeSi(SiMe3)3 ('sitel') ligand were reported. Sitel complexes of calcium, strontium and barium were obtained from the reaction of the metal silylamides with HTeSi(SiMe3)3 in hexane. The complex (Mg(12-C-4)2)(TeSi(SiMe3)3)2 produced from the reaction of the magnesium derivative with 12-crown-4 was isolated as the THF salt and structurally characterized.

The reaction between (octaethylporphyrin OEP)ZrCl2 and Na2C2B9H11 in tetrahydrofuran produced (OEP)Zr(n5-7,8-C2B9H11) in 74% yield. The resulting compound contained a carborane and a porphyrin moiety attached to the same zircon metal forming a pi-sandwich structure. Mass spectrometry, nuclear magnetic resonance spectroscopy and X-ray crystallographic measurements were conducted to identify the structural properties of the compound.

The reaction of (THF)4Li2(OEP) with ZrCl4(THT)2 produced the cis-dichloride complex (OEP)ZrCl2. The resulting compound efficiently served as a reagent in the formulation of different metalloporphyrin derivatives. Furthermore, structural studies using nuclear magnetic resonance and X-ray analyses showed that the complex mediated the catalytic hydrogenation of terminal olefins. Additional reactivity experiments were conducted to determine the chemical properties of the complex.

Modifications to a distillation-free solvent purification system are suggested. Advantages over distillation from a suitable drying agent are several and include large quantities of solvent being available on demand, no heat and no electricity being needed, and the greater safety of the procedure. Ethereal solvents have not been successfully purified with the method, but hexanes, pentane, toluene, benzene and dichloromethane have been.The system costs about $1200 per unit, about half that of an alternative system, and the alternate uses nonrenewable, expensive oxygen scavenger.

The title compound, [Fe(C15H15ClNS)(C14H16N)], crystallizes with the thiocarbamoyl chloride unit nearly coplanar with the cyclopentadienyl ring to which it is attached. There is a slight deviation from planarity which, along with the orientation of the amino substituent on the other cyclopentadienyl ring, is suggestive of an intramolecular hydrogen bond. The long donor-acceptor N…S length of 3.702 (2) Å indicates that any interaction is weak. [ABSTRACT FROM AUTHOR]

The title compound, [VCI(C7H7N){Fe(C8H13NSi)2}] or [FeV(C7H7N)(C8H13NSi)2Cl], crystallizes with the aromatic ring in the p-tolylimido unit parallel to the two cyclopentadienyl rings of the ferrocene moiety; the vanadium-bound chloride ion also lies in the plane occupied by the imido ligand. A mirror plane bisects the molecule through the V atom, the imido ligand and the Fe atom. [ABSTRACT FROM AUTHOR]