75-16-1Relevant articles and documents
Low-Temperature Reactions of Metal Atoms with Methyl Bromide
Tanaka, Yasutaka,Davis, Stephen C.,Klabunde, Kenneth J.
, p. 1013 - 1016 (1982)
The atoms of a series of metals were codeposited with CH3Br under matrix conditions (argon diluent at 12 K and pure CH3Br at 77 K).Oxidative addition of CH3Br to Fe, Co, Ni, and Pd did not occur upon simple codeposition or upon matrix photolysis, which is rationalized by the formation of a favored CH3Br-M complex.Cu, Ag, and Au behaved similary.Main-group metals Mg, Al, Ga, and In did react to form CH3MBr whereas Zn, Tl, Ge, Sn, and Pb did not.For the group 1B - 4B (Cu, Zn, B, C) families the most important reactivity parameter is a low ionization potential.However, a high heat of vaporization of the element also has a positive effect on reactivity.In the case of Mg, clusters may be necessary for high reactivity.
Method for preparing 1, 1 and 1 -trifluoro -2 -methyl -2 - propanol
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Paragraph 0042, (2021/12/07)
The invention discloses a method for preparing 1, 1 and 1 -trifluoro -2 -methyl -2 - propanol. To the method, methyl magnesium halide Grignard reagent is prepared from halogenated methane as a raw material in ether solvents, 1, 1 and 1 - trifluoroacetone are reacted in the presence of a catalyst to obtain 1, 1, 1 -trifluoro -2 -methyl -2 -propanol. The method has the advantages of easily available raw materials, convenience in post-treatment and purification, simplicity in operation, relatively low cost, high yield and the like.
Cross-coupling of aryl/alkenyl silyl ethers with grignard reagents through nickel-catalyzed CO bond activation
Zhao, Fei,Yu, Da-Gang,Zhu, Ru-Yi,Xi, Zhenfeng,Shi, Zhang-Jie
supporting information; experimental part, p. 1001 - 1003 (2011/12/05)
CO activation and its application have drawn much attention since oxygen-based electrophiles are easily available, less toxic, and more environmentally benign. This letter presents systematically results on the Ni-catalyzed KumadaTamaoCorriu coupling based on siloxy arenes/alkenes, which provides a new strategy of silyl protection/CC bond formation sequence in organic synthesis.
Enantioselective copper-catalysed allylic alkylation of cinnamyl chlorides by Grignard reagents using chiral phosphine-phosphite ligands
Loelsberg, Wibke,Ye, Shute,Schmalz, Hans-Guenther
supporting information; experimental part, p. 2023 - 2031 (2010/10/21)
The copper(I)-catalysed SN2'-type allylic substitution of E-3-aryl-allyl chlorides (cinnamyl chlorides) using Grignard reagents represents a powerful method for the synthesis of compounds carrying a benzylic stereocentre. By screening a small library of modular chiral phosphine-phosphite ligands a new copper(I)-based catalyst system was identified which allows the performance of such reactions with exceptional high degrees of regio- and enantioselectivity. Best results were obtained using TADDOLderived ligands (3 mol%), copper(I) bromide?dimethyl sulfide (CuBr?SMe2) (2.5 mol%) and methyl tert-butyl ether (MTBE) as a solvent. Various (1- alkyl-allyl)benzene derivatives were prepared with up to 99% ee (GC) in isolated yields of up to 99%. In most cases the product contained less than 3% of the linear regioisomer (except for ortho-substituted substrates). Both electron-rich and electron-deficient cinnamyl chlorides were successfully employed. The absolute configuration of the products was assigned by comparison of experimental and calculated CD spectra. The substrates were prepared from the corresponding alcohols by reaction with thionyl chloride. Initially formed mixtures of regioisomeric allylic chlorides were homogenised by treatment with CuBr?SMe2 (2.5 mol%) in the presence of triphenyl phosphine (PPh3) (3 mol%) in MTBE at low temperature to give the pure linear isomers. In reactions with methylmagnesium bromide (MeMgBr) an ortho-diphenylphosphanyl-arylphosphite ligand with an additional phenyl substituent in ortho'-position at the aryl backbone proved to be superior. In contrast, best results were obtained in the case of higher alkyl Grignard reagents (such as ethyl-, n-butyl-, isopropyl-, and 3-butenylmagnesium bromides) with a related ligand carrying an isopropyl substituent in ortho'-position. The method was tested on a multimmol scale and is suited for application in natural product synthesis.
Interior surface modifications of molecular sieves with organometallic reagents and the use thereof for the conversion of oxygenates to olefins
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, (2008/06/13)
A method for making an organometallic treated molecular sieve is described in which a molecular sieve having at least one hydroxyl group and at least [AlO2] and [PO2] tetrahedral units and having an average pore dimension less than or equal to about 5? is contacted with a solution comprising an organometallic compound and a non-proton donating solvent. The resulting organometallic treated molecular sieve has enhanced ethylene and/or propylene selectivity when used in the conversion of organic oxygenates to olefins. The ethylene and/or propylene selectivity, as well as catalyst life, are further enhanced when the resulting organometallic treated molecular sieve is combined with an oxide of at least one metal selected from Groups 2, 3 and Group 4 of the Periodic Table.
Process for the preparation of alicyclic ketones and an alkyl-substituted alicyclic esters
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, (2008/06/13)
A high-purity alicyclic ketone which is a raw material for an alkyl-substituted alicyclic ester such as an alkyl adamantyl ester compound which is useful as a resist raw material can be obtained by a simple operation such as extraction without a special purification step such as distillation or recrystallization. In this process, when an alicyclic hydrocarbon is oxidized with concentrated sulfuric acid or fuming sulfuric acid, the reaction solution after oxidation is poured into water and a solid is extracted with an organic solvent, the concentration of sulfuric acid in the water layer at the time of extraction is adjusted to 60 to 90 wt % to carry out extraction so as to obtain an alicyclic ketone.
Adamantanemethanol derivatives and production processes thereof
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Example 4, (2008/06/13)
An adamantanemethanol derivative of the invention is represented by the following formula (1), wherein Rais a hydrogen atom or a hydrocarbon group; Rbis a hydrocarbon group having a carbon atom, to which carbon atom at least one hydrogen atom is bonded, at a bonding site with the adjacent carbon atom; Rc, Rdand Reare each a hydrogen atom, a hydroxyl group which may be protected by a protective group or the like; provided that a hydroxyl group protected by a protective group or the like is bonded to at least one carbon atom constituting the adamantane skeleton when Rais a hydrogen atom or a methyl group and Rbis a methyl group; and at least one substituent, in addition to the HO—C(Ra)(Rb)— group indicated in the formula (1), is bonded to the adamantane ring when one of Raand Rbis a methyl group and the other is an ethyl group.
2,3-oxidosqualene-lanosterol cyclase inhibitors
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, (2008/06/13)
The present invention relates to aminocyclohexanol derivatives useful for the treatment and/or prophylaxis of diseases which are associated with 2,3-oxidosqualene-lanosterol cyclase such as hypercholesterolemia, hyperlipemia, arteriosclerosis, vascular diseases, mycoses, gallstones, tumors and/or hyperproliferative disorders, and treatment and/or prophylaxis of impaired glucose tolerance and diabetes.
An ESR and HPLC-EC assay for the detection of alkyl radicals
Novakov,Feierman,Cederbaum,Stoyanovsky
, p. 1239 - 1246 (2007/10/03)
The correlation of lipid peroxidation with release of alkanes (RH) is considered a noninvasive method for the in vivo evaluation of oxidative stress. The formation of RH is believed to reflect a lipid hydroperoxide (LOOH)-dependent generation of alkoxyl radicals (LO·) that undergo β-scission with release of alkyl radicals (R·). Alternatively, R· could be spin-trapped with a nitrone before the formation of RH and analyzed by ESR. Extracts from the liver and lung of CCl4- and asbestos-treated rats that were previously loaded with nitrones exhibited ESR spectra suggesting the formation of iso-propyl, n-butyl, ethyl, and pentyl radical-derived nitroxides. In biological systems, various nitroxides with indistinguishable ESR spectra could be formed. Hence, experiments with N-tert-butyl-α-phenylnitrone (PBN) for spin trapping of R· were carried out in which the nitroxides formed were separated and analyzed by HPLC with electrochemical detection (EC). The C1-5 homologous series of PBN nitroxides and hydroxylamines were synthesized, characterized by ESR, GC-MS, and HPLC-EC, and used as HPLC standards. For in vivo generation and spin trapping of R·, rats were loaded with CCl4 and PBN. The HPLC-EC chromatograms of liver extracts from CCl4-treated rats demonstrated the formation of both the nitroxide and hydroxylamine forms of PBN/·CCl3, as well as the formation of a series of unidentified PBN nitroxides and hydroxylamines. However, formation of PBN adducts with retention times similar to these of the PBN/C2-5 derivatives was not observed. In conclusion, we could not correlate the production of PBN-detectable alkyl radicals with the reported CCl4-dependent production of C1-5 alkanes. We speculate that the major reason for this is the low steady-state concentrations of R· produced because only a small fraction of LO· undergo β-scission to release R·.
Alkyl tetralin aldehyde compounds
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, (2008/06/13)
The present invention relates, inter alia, to novel alkyl tetralin aldehyde compounds having fragrant musk-like aroma.