Methane-, lithium

Strong acids or superacid systems generate stable fluorinated carbocations [40, 42] Treatment of tetrafluorobenzbarrelene with arenesulfonyl chlorides in nitro-methane-lithium perchlorate yields a crystalline salt with a rearranged benzo barrelene skeleton [43] Ionization of polycyclic adducts of difluorocarbene and derivatives of bornadiene with antimony pentafluonde in fluorosulfonyl chloride yields stable cations [44, 45]... 

An aiyl methane- or toluenesulfonate ester is stable to reduction with lithium aluminum hydride, to the acidic conditions used for nitration of an aromatic ring (HNO3/HOAC), and to the high temperatures (200-250°) of an Ullman reaction. Aiyl sulfonate esters, formed by reaction of a phenol with a sulfonyl chloride in pyridine or aqueous sodium hydroxide, are cleaved by warming in aqueous sodium hydroxide. ... 

The lithium oxide-promoted barium oxide also functions as a catalyst for the methane coupling reaction, but the mechanism is not clearly understood at the present time. The only comment that might be offered here is that the presence of ions on the surface of this material might etdrance the formation of methyl radicals drrough the formation of hydroxyl groups thus... 

Other methods for the preparation of cyclohexanecarboxaldehyde include the catalytic hydrogenation of 3-cyclohexene-1-carboxaldehyde, available from the Diels-Alder reaction of butadiene and acrolein, the reduction of cyclohexanecarbonyl chloride by lithium tri-tcrt-butoxy-aluminum hydride,the reduction of iV,A -dimethylcyclohexane-carboxamide with lithium diethoxyaluminum hydride, and the oxidation of the methane-sulfonate of cyclohexylmethanol with dimethyl sulfoxide. The hydrolysis, with simultaneous decarboxylation and rearrangement, of glycidic esters derived from cyclohexanone gives cyclohexanecarboxaldehyde. 

Problem 1.8 concerned the charge distribution in methane (CH4), chloromethane (CH3CI), and methyllithium (CH3Li). Inspect molecular models of each of these compounds, and compare them with respect to how charge is distributed among the various atoms (carbon, hydrogen, chlorine, and lithium). Compare their electrostatic potential maps. 

The first clearly authenticated preparation of an isoindole was reported by Wittig et in 1951. It was found that elimination from isoindolinium bromides and iodides with bases such as aryl- and alkyllithium afforded 2-substituted isoindoles in variable yields. For instance, 2,2-dimethylisoindolinium bromide (5) on treatment with one equivalent of phenyllithium in ether under nitrogen, evolved methane and gave 2-mcthylisoindole (6) in 74% yield. With methyl-lithium as base, a slightly lower yield was obtained. 

CK-Hvdroxy-9CK-fluorohydrocortlsone acetonide Methane sulfonyl chloride Lithium chloride... 

Cl Methylation of the 16/-3-benzazepine 1 to give 2 is effected in quantitative yield with iodo-methane in the presence of lithium diisopropylamide.61... 

Because carbon bonds so readily with itself, there are many hydrocarbons (see Chapter 18). Silicon forms a much smaller number of compounds with hydrogen, called the silanes. The simplest silane is silane itself, SiH4, the analog of methane. Silane is formed by the action of lithium aluminum hydride on silicon halides in ether ... 

Quartare Methyl-ammonium-Salze lassen sich mit Lithium al an at unter Entwicklung von Methan zu tert. Aminen demethylieren3,4 ... 

Bis(diphenylphosphino)methyl-lithium, from methyl-lithium and bis-(diphenylphosphino)methane, gave the compound (1) with chlorodiphenyl-phosphine. ... 

T. Ito and J. H. Lunsford, Synthesis of ethylene and ethane by partial oxidation of methane over lithium-doped magnesium oxide, Nature, 1985, 314, 721. 

We came up with the idea of using a dummy ligand, as shown in Scheme 1.23 [34]. Reaction of dimethylzinc with our chiral modifier (amino-alcohol) 46 provided the methylzinc complex 62, which was subsequently reacted with 1 equiv of MeOH, to form chiral zinc alkoxide 63, generating a total of 2 moles of methane. Addition of lithium acetylide to 63 would generate an ate complex 64. The ate complex 64 should exist in equilibrium with the monomeric zincate 65 and the dimer 66. However, we expected that the monomer ate complex 64 and the mono-... 

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