2.2.1. Diaminoand Aminohydrazinocarbenes 3338 2.2.2. Aminothioand Aminooxycarbenes 3340 2.3. Phosphinoaryland Phosphinoalkylcarbenes 3341 2.4. Aminoaryland Aminoalkylcarbenes 3344 2.5. Aminophosphonio and Aminosilylcarbenes 3346 2.6. Aminophosphinocarbenes 3347 3. Reactivity 3348 3.1. Typical Carbene Behavior 3348 3.1.1. Coupling Reactions 3348 3.1.2. Cycloaddition Reactions 3352 3.1.3. Insertion Reactions 3355 3.1.4. Migration Reactions 3358 3.2. Basic/Nucleophilic Behavior 3359 3.2.1. Protonation of Carbenes 3359 3.2.2. Reactions with Group 14 Electrophiles 3360 3.2.3. Reactions with Group 13 Lewis Acids 3360 3.2.4. Reactions with Group 15 Electrophiles 3361 3.3. Electrophilic Behavior 3362 3.3.1. Reaction with 1,5-Diazabicyclo[4.3.0]non-5-ene (DBN) 3362

Stable Noncyclic Singlet Carbenes

Publisher Summary This chapter discusses copper complexes that offer a physiological approach to the treatment of chronic diseases. Copper is recognized as an essential metalloelement just as sodium, potassium, magnesium, calcium, iron, zinc, chromium, vanadium, and manganese. Just as essential amino acids, essential fatty acids and essential cofactors (vitamins), essential metalloelements are required for normal metabolic processes but cannot be synthesized de novo, and daily dietary intake and absorption are required. The adult body contains between 1.4 mg (22 pmol) and 2.1 mg (33 pmol) of copper per kilogram of body weight while the infant body contains three times this amount, consistent with the fact that infant metabolic needs are that much greater than those of adults. The essentiality of copper is now understood as being based upon its recognized need for activation of copper-dependent enzymes. Complexed forms of copper also facilitate absorption, tissue distribution, and tissue utilization. In the nondisease state, these forms of copper account for the physiologic regulation of copper-dependent homeostatic processes. Consistent with the newly found role for copper in synthesis of neuroendocrine peptides, the copper complex of histidine has been found to increase the secretion of luteinizing hormone-releasing hormone (LH-RH) from granules of the median eminence.

Copper complexes offer a physiological approach to treatment of chronic diseases.

Transition metal compounds are well known as activators of small molecules, and they serve as efficient catalysts for a variety of homogeneous and heterogeneous transformations. In contrast, there ...

Group 14 hydrides with low valent elements for activation of small molecules.

Two nickel(II) complexes of formula (H3dien)2[Ni2(ox)5]·12H2O (1) and [Ni2(dien)2(H2O)2(ox)]Cl2 (2) (dien = diethylenetriamine and ox = oxalate dianion) have been synthesized and characterized by single-crystal X-ray diffraction. 1 crystallizes in the orthorhombic system, space group Abnn, with a = 15.386(4) A, b = 15.710(4) A, c = 17.071(4) A, and Z = 4. 2 crystallizes in the monoclinic system, space group P21/c, with a = 10.579(1) A, b = 7.258(1) A, c = 13.326(1) A, β = 93.52(3)°, and Z = 2. The structures of 1 and 2 consist of dinuclear oxalato-bridged nickel(II) units which contain bidentate oxalate (1) and tridentate dien in the fac-conformation (2) as terminal ligands. Both features, oxalato as a peripheral ligand and dien in the fac-conformation (instead of its usual mer-conformation), are unprecedented in the coordination chemistry of nickel(II). The nickel atom is six-coordinated in both compounds, the chromophores being NiO6 (1) and NiN3O3 (2). The Ni−O(ox) bond distances at the bridge (2.072(4)...

Influence of the Peripheral Ligand Atoms on the Exchange Interaction in Oxalato-Bridged Nickel(II) Complexes: An Orbital Model. Crystal Structures and Magnetic Properties of (H3dien)2[Ni2(ox)5]·12H2O and [Ni2(dien)2(H2O)2(ox)]Cl2

Chiral metal-organic frameworks (MOFs) have attracted a growing interest for their potential use in energy technologies, asymmetric catalysis, chiral separation, and on a more basic level, the creation of new topologies in inorganic materials. The current paper is the first report on a peptide-based MOF, a metal peptide framework (MPF), constructed from an oligovaline peptide family developed earlier by our group (Mantion, A.; et al. Macromol. Biosci. 2007, 7, 208). We have used a simple oligopeptide, Z-(l-Val)2-l-Glu(OH)-OH, to grow porous copper and calcium MPFs. The MPFs form thanks to the self-assembling properties of the peptide and specific metal−peptide and metal−ammonia interactions. They are stable up to ca. 250 °C and have some internal porosity, which makes them a promising prototype for the further development of MPFs.

Metal-peptide frameworks (MPFs): "Bioinspired" metal organic frameworks

Crystal and molecular structures of transition metal complexes with N- and C-bonded diazoalkane ligands

Oxygen atom transfer reactions. 2. Reaction of carbon monoxide with Ni(NO2)2(PMe3)2: structure of nitronitrosylbis(trimethylphosphine)nickel, Ni(NO2)(NO)(PMe3)2

Methylnickel compounds with chelating anionic ligands. Crystal and molecular structures of methyl(trimethylphosphine)nickel oxinate and oxalate dimer

Spectral and Electron Paramagnetic Resonance Investigations of Copper(II) Complexes of Linear-Chain Fatty Diacids

Heating of bis[bis(diisopropylamino)phosphanyl]diazomethane 7. in refluxing benzene for 48 hours, quantitatively led to the corresponding 1.2λ3-azaphosphetane 9 as only one diastereoisomer. This result is explained in terms of carbene insertion into a methin-CH bond of an isopropyl substituent. The regiospecificity and the stereospecificity of the ring closure is discussed. Treatment of 9 with elemental sulfur afforded the corresponding 1.2.2λ3-azathiophosphetane 10 which has been characterized b X ray crystallo raphy: C25H56N4P2S2, space group P2(l)/n, a = 13.628 (3) A, 6 = 19.369 (5) A, c 112.485 (4) A, V = 3073 (3) A3.

Y. Dartiguenave

Papers

Crystal and molecular structures of transition metal complexes with N- and C-bonded diazoalkane ligands

Oxygen atom transfer reactions. 2. Reaction of carbon monoxide with Ni(NO2)2(PMe3)2: structure of nitronitrosylbis(trimethylphosphine)nickel, Ni(NO2)(NO)(PMe3)2

Methylnickel compounds with chelating anionic ligands. Crystal and molecular structures of methyl(trimethylphosphine)nickel oxinate and oxalate dimer

Spectral and Electron Paramagnetic Resonance Investigations of Copper(II) Complexes of Linear-Chain Fatty Diacids

STEREOSPECIFIC FORMATION OF A 1,2λ3 -AZAPHOSPETANE IN THE THERMOLYSIS OF BIS[BIS(DIISOPROPYLAMINO)PHOSPHANYL] DIAZOMETHANE