The stereochemistry of organometallic compounds. XXIV. Nickel(0)-catalysed additions of hydrogen cyanide to alkynes

1983 ◽  
Vol 36 (10) ◽  
pp. 1975 ◽  
Author(s):  
WR Jackson ◽  
CG Lovel
Keyword(s):  
Hydrogen Cyanide ◽  
Organometallic Compounds ◽  
Triphenyl Phosphite ◽  
Wide Range

Hydrogen cyanide will add to alkynes bearing a wide range of substituents with cis stereospecificity, high regioselectivity, and in moderate-to-good yields, when the reaction is catalysed by tetrakis- (triphenyl phosphite)nickel(0).

The Stereochemistry of Organometallic Compounds. XXVIII. The Nickel-Catalyzed Addition of Hydrogen Cyanide to Aliphatic Dienes

1987 ◽  
Vol 40 (6) ◽  
pp. 1053 ◽  
Author(s):  
EM Campi ◽  
PS Elmes ◽  
WR Jackson ◽  
CG Lovel ◽  
MKS Probert
Keyword(s):  
Hydrogen Cyanide ◽  
Organometallic Compounds ◽  
Mechanism Of Reaction ◽  
Wide Range ◽  
High Yields ◽  
Very High

Reaction of hydrogen cyanide with a wide range of aliphatic dienes in the presence of nickel(0) catalysts leads to rearrangement of the diene and formation of β,γ -unsaturated nitriles in moderate to very high yields. The mechanism of reaction is discussed in terms of π-allyl-nickel intermediates.

scholarly journals Hypergolic Synthesis of Inorganic Materials by the Reaction of Metallocene Dichlorides With Fuming Nitric Acid At Ambient Conditions: The Case of Photocatalytic Titania

2021 ◽  
Author(s):  
Nikolaos Chalmpes ◽  
Georgios Asimakopoulos ◽  
Maria Baikousi ◽  
Athanasios B. Bourlinos ◽  
Michael A. Karakassides ◽  
...  
Keyword(s):  
Nitric Acid ◽  
Materials Science ◽  
Organometallic Compounds ◽  
Inorganic Materials ◽  
Titania Nanoparticles ◽  
Titanocene Dichloride ◽  
Ambient Conditions ◽  
Materials Synthesis ◽  
Wide Range ◽  
Fuming Nitric Acid

Hypergolic materials synthesis is a new preparative technique in materials science that allows a wide range of carbon or inorganic solids with useful properties to be obtained. Previously we have demonstrated that metallocenes are versatile reagents in the hypergolic synthesis of inorganic materials, such as γ-Fe2O3, Cr2O3, Co, Ni and alloy CoNi. Here, we take one step further by using metallocene dichlorides as precursors for the hypergolic synthesis of additional inorganic phases, such as photocatalytic titania. Metallocene dichlorides are closely related to metallocenes, thus expanding the arsenal of organometallic compounds that can be used in hypergolic materials synthesis. In the present case, we show that hypergolic ignition of the titanocene dichloride-fuming nitric acid pair results in the fast and spontaneous formation of titania nanoparticles at ambient conditions in the form of anatase-rutile mixed phases. The obtained titania shows good photocatalytic activity towards Cr(VI) removal (100 % within 9 h), the latter being dramatically enhanced after calcination of the powder at 500 °C (100 % within 3 h). Worth noting, this performance was found to be comparable to that of commercially available P25 TiO2 under identical conditions. The cases of zirconocene, hafnocene and molybdocene dichlorides are complementary discussed in this work, aiming to show the wider applicability of metallocene dichlorides in the hypergolic synthesis of inorganic materials (ZrO2, HfO2, MoO2).

scholarly journals Origin of Life’s Building Blocks in Carbon- and Nitrogen-Rich Surface Hydrothermal Vents

Life ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 12 ◽  
Author(s):  
Paul Rimmer ◽  
Oliver Shorttle
Keyword(s):  
Hydrogen Cyanide ◽  
Hydrothermal Vents ◽  
Prebiotic Chemistry ◽  
Organometallic Compounds ◽  
Building Blocks ◽  
Hydrothermal Systems ◽  
Subsurface Water ◽  
Geochemical Environment ◽  
Carbon And Nitrogen ◽  
Submarine Hydrothermal Systems

There are two dominant and contrasting classes of origin of life scenarios: those predicting that life emerged in submarine hydrothermal systems, where chemical disequilibrium can provide an energy source for nascent life; and those predicting that life emerged within subaerial environments, where UV catalysis of reactions may occur to form the building blocks of life. Here, we describe a prebiotically plausible environment that draws on the strengths of both scenarios: surface hydrothermal vents. We show how key feedstock molecules for prebiotic chemistry can be produced in abundance in shallow and surficial hydrothermal systems. We calculate the chemistry of volcanic gases feeding these vents over a range of pressures and basalt C/N/O contents. If ultra-reducing carbon-rich nitrogen-rich gases interact with subsurface water at a volcanic vent they result in 10 − 3 – 1 M concentrations of diacetylene (C4H2), acetylene (C2H2), cyanoacetylene (HC3N), hydrogen cyanide (HCN), bisulfite (likely in the form of salts containing HSO3−), hydrogen sulfide (HS−) and soluble iron in vent water. One key feedstock molecule, cyanamide (CH2N2), is not formed in significant quantities within this scenario, suggesting that it may need to be delivered exogenously, or formed from hydrogen cyanide either via organometallic compounds, or by some as yet-unknown chemical synthesis. Given the likely ubiquity of surface hydrothermal vents on young, hot, terrestrial planets, these results identify a prebiotically plausible local geochemical environment, which is also amenable to future lab-based simulation.

Studies in polymerization - XXII. Initiation of polymerization by reaction between tetrakis(triphenyl phosphite)nickel(0) and halides: methyl methacrylate

1972 ◽  
Vol 326 (1567) ◽  
pp. 469-487 ◽  
Keyword(s):  
Methyl Methacrylate ◽  
Kinetic Studies ◽  
Triphenyl Phosphite ◽  
Wide Range ◽  
Absolute Rate Constant ◽  
Entropy Of Activation ◽  
Enthalpy And Entropy Changes ◽  
Enthalpy And Entropy ◽  
Kinetics Of ◽  
Initiation Of Polymerization

Tetrakis(triphenyl phosphite)nickel(0) (NiP 4 ) in solution in methyl methacrylate (MMA) undergoes reversible ligand exchange to form a species NiP 3 (MMA). Kinetic studies based on absorbance measurements are consistent with the view that a rate-controlling dissociation of NiP 4 is followed by rapid and almost complete complexing of NiP 3 with MMA. The enthalpy and entropy of activation for the dissociation have been determined, and also the standard enthalpy and entropy changes for the overall reaction. The initiation of polymerization which occurs in the presence of carbon tetrachloride has been shown to arise from reaction between NiP 3 (MMA) and CCI 4 , and the absolute rate constant of this process has been measured at various temperatures. Each NiP 3 (MMA) yields approximately one free radical, and it is thought that the final product is a Ni II derivative. Part of the oxidation must therefore proceed by a route which does not form radicals. The kinetics of the overall polymerization have been investigated by numerical solution of the appropriate differential equations, using the parameters evaluated, without any stationary state assumptions about the concentration of species involved in initiation. The agreement with experiment is satisfactory over a wide range of conditions.

scholarly journals Твердые растворы In-=SUB=-x-=/SUB=-Al-=SUB=-1-x-=/SUB=-N: проблемы стабильности состава

2019 ◽  
Vol 53 (12) ◽  
pp. 1733
Author(s):  
В.Н. Брудный ◽  
М.Д. Вилисова ◽  
Л.Э. Великовский
Keyword(s):  
Gas Phase ◽  
Molecular Beam ◽  
Organometallic Compounds ◽  
Growth Conditions ◽  
Equilibrium Solubility ◽  
High Quality ◽  
Gan Hemt ◽  
Wide Range ◽  
Growing Conditions ◽  
Thick Layers

Abstract. The phase diagrams and growth conditions of InxAl1-xN solid solutions by magnetron sputtering, molecular beam and gas-phase epitaxy from organometallic compounds are analyzed. Mutual equilibrium solubility in a wide range of compositions of thick layers of this solution is close to zero. Moreover, the presence of elastic misfit stresses for thin InxAl1-xN films narrows the unstable mixing region. Optimization of the growing conditions makes it possible to obtain the homogeneous high-quality InxAl1-xN layers suitable for the production of a barrier layer in an InAlN/GaN HEMT.

The Stereochemistry of Organometallic Compounds. XXXI. Hydrocyanation of Alkynols

1988 ◽  
Vol 41 (7) ◽  
pp. 1099 ◽  
Author(s):  
WR Jackson ◽  
CG Lovel ◽  
P Perlmutter ◽  
AJ Smallridge
Keyword(s):  
Organometallic Compounds ◽  
Catalyst System ◽  
Steric Effects ◽  
Triphenyl Phosphite ◽  
Catalyst Systems

The regioselectivity of hydrocyanation of a range of alkynols using nickel-based catalyst systems involving either triphenyl phosphite or α,α′-bis(diphenylphosphino)-o-xylene (phmep) has been investigated. The regioselectivity of the hydrocyanations involving the phosphine catalyst reflected dominant steric effects whereas results from the phosphite catalyst system showed some evidence for chelation control. Yields of nitriles from reactions based on the phosphite system were variable, whereas moderate to good yields of distilled products could be obtained consistently by using the phosphine -based system. An explanation for this variation in yield is proposed.

The stereochemistry of organometallic compounds. XXII. The stereochemistry of metal-catalysed hydrogen cyanide addition to olefins

1982 ◽  
Vol 35 (10) ◽  
pp. 2053 ◽  
Author(s):  
WR Jackson ◽  
CG Lovel
Keyword(s):  
Zinc Chloride ◽  
Hydrogen Cyanide ◽  
Isotopic Exchange ◽  
Organometallic Compounds ◽  
Catalyst System

Reactions of (E)-3,3-dimethyl(1,2-D2)but-1-ene with hydrogen cyanide and of (E)-3,3-dimethyl-(1-D)but-1-ene with deuterium cyanide have been shown to proceed in a completely stereospecific cis fashion when a catalyst system based on Pd(diop)2 was used. Reaction between 4-t-butylcyclo-hexene and deuterium cyanide with the catalyst system gave only the equatorial nitriles trans- 4-t-butylcyclohexane-1-carbonitrile and cis-3-t-butylcyclohexane-1-carbonitrile with cis incorporation of deuterium. Use of a catalyst system based on Ni[P(OPh)3]4 and zinc chloride led to significant amounts of isotopic exchange and rearrangement. These results are compared with those from hydroformylation of the olefins, and the mechanism of hydrocyanation is discussed.

Elemental Speciation Measurements with Electrospray Mass Spectrometry: An Assessment

1994 ◽  
Vol 48 (11) ◽  
pp. 1347-1359 ◽  
Author(s):  
George R. Agnes ◽  
Ian I. Stewart ◽  
Gary Horlick
Keyword(s):  
Mass Spectrometry ◽  
Electrospray Mass Spectrometry ◽  
Molecular Form ◽  
Direct Determination ◽  
Organometallic Compounds ◽  
Ionic Species ◽  
Elemental Speciation ◽  
Wide Range ◽  
Inorganic Complexes

Electrospray mass spectrometry (ES-MS) is shown to be suited for the direct determination of ionic species in solution. Examples used in this investigation of ES-MS for elemental speciation determinations included several inorganic ionic species of chlorine, iodine, sulfur, and iron. These species were differentiated on the basis of differences in the molecular form and/or the oxidation state of the analyte ion. The inorganic complexes of silver-cyanide and iron-fluoride were also measured in this assessment. Finally it is shown that ES-MS is applicable to the determination of organometallic compounds. While ES-MS is not an ideal speciation technique, there is considerable evidence to indicate that ES-MS can become an invaluable tool with which species distributions in a wide range of sample types may be probed.

The stereochemistry of organometallic compounds. XXI. Asymmetric addition of hydrogen cyanide to alkenes catalysed by zerovalent metal compounds

1982 ◽  
Vol 35 (10) ◽  
pp. 2041 ◽  
Author(s):  
PS Elmes ◽  
WR Jackson
Keyword(s):  
Hydrogen Cyanide ◽  
Organometallic Compounds ◽  
Asymmetric Addition ◽  
Metal Compounds

[(+)-(diop)]2Pd and [(+)-(diop)]2Ni have been prepared and used as catalysts for the asymmetric addition of hydrogen cyanide to alkenes. The corresponding complex of platinum with diop has also been prepared and found to be less useful as a catalyst as were the complexes of these three metals with other chelating diphosphines.

scholarly journals Synthesis, Characterization and Biological Studies of Some Organotin Compounds: (A-Review)

2020 ◽  
Vol 36 (05) ◽  
pp. 871-878
Author(s):  
Priyanka Siwacha ◽  
Surbhi Soni ◽  
Harish Kumar Sharmaa ◽  
Manoj Kumara
Keyword(s):  
Amino Acids ◽  
Biological Activities ◽  
Organometallic Compounds ◽  
Molecular Structures ◽  
Organotin Compounds ◽  
Single Source ◽  
Biological Studies ◽  
Hybrid Complex ◽  
Wide Range ◽  
Significant Attention

Significant attention has been given to organotin (IV) amino acids compounds in recent years. Organometallic compounds are better known for their potentiality to stabilize peculiar stereochemistry of their complexes and application in agriculture, catalysis and as single source precursors. Due to the better stability and diverse molecular structures the complexes own a wide range of biological activities. These individual properties create an alliance of action in the hybrid complex. In this review, we discuss the chemistry of organotin (IV) complexes and their different aspects in various fields. The aim of the present review is to evaluate the synthesis, characterization and biological activities of organotin compounds.

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