A Ziegler–Natta catalyst, named after Karl Ziegler and Giulio Natta, is a catalyst used in the synthesis of polymers of 1-alkenes (alpha-olefins). Two broad classes of Ziegler–Natta catalysts are employed, distinguished by their solubility:
Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organic compounds. Hydrogenation typically constitutes the addition of pairs of hydrogen atoms to a molecule, often an alkene. Catalysts are required for the reaction to be usable; non-catalytic hydrogenation takes place only at very high temperatures. Hydrogenation reduces double and triple bonds in hydrocarbons.
The Sonogashira reaction is a cross-coupling reaction used in organic synthesis to form carbon–carbon bonds. It employs a palladium catalyst as well as copper co-catalyst to form a carbon–carbon bond between a terminal alkyne and an aryl or vinyl halide.
Grubbs catalysts are a series of transition metal carbene complexes used as catalysts for olefin metathesis. They are named after Robert H. Grubbs, the chemist who supervised their synthesis. Several generations of the catalyst have also been developed. Grubbs catalysts tolerate many functional groups in the alkene substrates, are air-tolerant, and are compatible with a wide range of solvents. For these reasons, Grubbs catalysts have become popular in synthetic organic chemistry. Grubbs, together with Richard R. Schrock and Yves Chauvin, won the Nobel Prize in Chemistry in recognition of their contributions to the development of olefin metathesis.
DABCO (1,4-diazabicyclo[2.2.2]octane), also known as triethylenediamine or TEDA, is a bicyclic organic compound with the formula N2(C2H4)3. This colorless solid is a highly nucleophilic tertiary amine base, which is used as a catalyst and reagent in polymerization and organic synthesis.
The azide-alkyne Huisgen cycloaddition is a 1,3-dipolar cycloaddition between an azide and a terminal or internal alkyne to give a 1,2,3-triazole. Rolf Huisgen was the first to understand the scope of this organic reaction. American chemist Karl Barry Sharpless has referred to this cycloaddition as "the cream of the crop" of click chemistry and "the premier example of a click reaction".
Salen refers to a tetradentate C2-symmetric ligand synthesized from salicylaldehyde (sal) and ethylenediamine (en). It may also refer to a class of compounds, which are structurally related to the classical salen ligand, primarily bis-Schiff bases. Salen ligands are notable for coordinating a wide range of different metals, which they can often stabilise in various oxidation states. For this reason salen-type compounds are used as metal deactivators. Metal salen complexes also find use as catalysts.
Atom transfer radical polymerization (ATRP) is an example of a reversible-deactivation radical polymerization. Like its counterpart, ATRA, or atom transfer radical addition, ATRP is a means of forming a carbon-carbon bond with a transition metal catalyst. Polymerization from this method is called atom transfer radical addition polymerization (ATRAP). As the name implies, the atom transfer step is crucial in the reaction responsible for uniform polymer chain growth. ATRP was independently discovered by Mitsuo Sawamoto and by Krzysztof Matyjaszewski and Jin-Shan Wang in 1995.
In organic chemistry, a phosphite ester or organophosphite usually refers to an organophosphorous compound with the formula P(OR)3. They can be considered as esters of an unobserved tautomer phosphorous acid, H3PO3, with the simplest example being trimethylphosphite, P(OCH3)3. Some phosphites can be considered esters of the dominant tautomer of phosphorous acid (HP(O)(OH)2). The simplest representative is dimethylphosphite with the formula HP(O)(OCH3)2. Both classes of phosphites are usually colorless liquids.
In chemistry, transfer hydrogenation is a chemical reaction involving the addition of hydrogen to a compound from a source other than molecular H2. It is applied in laboratory and industrial organic synthesis to saturate organic compounds and reduce ketones to alcohols, and imines to amines. It avoids the need for high-pressure molecular H2 used in conventional hydrogenation. Transfer hydrogenation usually occurs at mild temperature and pressure conditions using organic or organometallic catalysts, many of which are chiral, allowing efficient asymmetric synthesis. It uses hydrogen donor compounds such as formic acid, isopropanol or dihydroanthracene, dehydrogenating them to CO2, acetone, or anthracene respectively. Often, the donor molecules also function as solvents for the reaction. A large scale application of transfer hydrogenation is coal liquefaction using "donor solvents" such as tetralin.
In organic chemistry, the Buchwald–Hartwig amination is a chemical reaction for the synthesis of carbon–nitrogen bonds via the palladium-catalyzed coupling reactions of amines with aryl halides. Although Pd-catalyzed C–N couplings were reported as early as 1983, Stephen L. Buchwald and John F. Hartwig have been credited, whose publications between 1994 and the late 2000s established the scope of the transformation. The reaction's synthetic utility stems primarily from the shortcomings of typical methods for the synthesis of aromatic C−N bonds, with most methods suffering from limited substrate scope and functional group tolerance. The development of the Buchwald–Hartwig reaction allowed for the facile synthesis of aryl amines, replacing to an extent harsher methods while significantly expanding the repertoire of possible C−N bond formations.
2,4,6-Trimethylaniline is an organic compound with formula (CH3)3C6H2NH2. It is an aromatic amine that is of commercial interest as a precursor to dyes. It is prepared by selective nitration of mesitylene, avoiding oxidation of the methyl groups, followed by reduction of the resulting nitro group to the aniline.
Organochromium chemistry is a branch of organometallic chemistry that deals with organic compounds containing a chromium to carbon bond and their reactions. The field is of some relevance to organic synthesis. The relevant oxidation states for organochromium complexes encompass the entire range of possible oxidation states from –4 (d10) in Na4[Cr–IV(CO)4] to +6 (d0) in oxo-alkyl complexes like Cp*CrVI(=O)2Me.
Organomolybdenum chemistry is the chemistry of chemical compounds with Mo-C bonds. The heavier group 6 elements molybdenum and tungsten form organometallic compounds similar to those in organochromium chemistry but higher oxidation states tend to be more common.
In polymer chemistry, chain walking (CW) or chain running or chain migration is a mechanism that operates during some alkene polymerization reactions. CW can be also considered as a specific case of intermolecular chain transfer. This reaction gives rise to branched and hyperbranched/dendritic hydrocarbon polymers. This process is also characterized by accurate control of polymer architecture and topology. The extent of CW, displayed in the number of branches formed and positions of branches on the polymers are controlled by the choice of a catalyst. The potential applications of polymers formed by this reaction are diverse, from drug delivery to phase transfer agents, nanomaterials, and catalysis.
Dehydrogenation of amine-boranes or dehydrocoupling of amine-boranes is a chemical process in main group and organometallic chemistry wherein dihydrogen is released by the coupling of two or more amine-borane adducts. This process is of due to the potential of using amine-boranes for hydrogen storage.
Diimines are organic compounds containing two imine (RCH=NR') groups. Common derivatives are 1,2-diketones and 1,3-diimines. These compounds are used as ligands and as precursors to heterocycles. Diimines are prepared by condensation reactions where a dialdehyde or diketone is treated with amine and water is eliminated. Similar methods are used to prepare Schiff bases and oximes.
1,2-Dimethylethylenediamine (DMEDA) is the organic compound with the formula (CH3NH)2C2H4. It is a colorless liquid with a fishy odor. It features two secondary amine functional groups.
A lanthanocene is a type of metallocene compound that contains an element from the lanthanide series. The most common lanthanocene complexes contain two cyclopentadienyl anions and an X type ligand, usually hydride or alkyl ligand.
Pentaethylenehexamine (abbreviated PEHA) is a organic amine. It is composed of five ethylene groups -CH2CH2- joined together in a chain by four secondary amine groups (-NH-) and terminated on each end by primary amine groups (-NH2). Pentaethylenehexamine is a hexadentate ligand, owing to the Lewis basicity of the six amine groups. Pentaethylenehexamine is in the category of polyethyleneamines and is part of mixtures of these sold commercially.
