Lithium triphenylmethyl *

Indenopyrans (45) which can be obtained after Schroth and Fischer from benzoxalenes (44) and lithium alkyls or aryls, are y-pyrans, and may be dehydrogenated by triphenylmethyl perchlorate to the indenopyrylium perchlorate (46). °... 

The low degree of ionization in ether does not necessarily mean that triarylmethyl sodium compounds are largely covalent in that solvent. They may still be highly polar. Lithium iodide, for example, is also a poor conductor in ether although a good one in water. The conductivity of triphenylmethyl sodium in pyridine is very much... 

To obtain complete conversion of ketones to enolates, it is necessary to use aprotic solvents so that solvent deprotonation does not compete with enolate formation. Stronger bases, such as amide anion ( NH2), the conjugate base of DMSO (sometimes referred to as the dimsyl anion),2 and triphenylmethyl anion, are capable of effecting essentially complete conversion of a ketone to its enolate. Lithium diisopropylamide (LDA), which is generated by addition of w-butyllithium to diisopropylamine, is widely used as a strong... 

Fur die regioselektive Metallierung von 4,5-unsubstituierten 1,2-disubstituierten Imidazolen in 4-Stellung ist in der Literatur nur cin Beispiel beschrieben (falls kein Irrtum bei der Struk-turermittlung vorliegt) 2-Fluor-l-triphenylmethyl-imidazol wurde mit tert.-Butyl-lithium und Dimethylformamid zu 2-Fluor-4-formyl-l-triphenylmethyl-imidazol umgesetzt1041. 

Essentially covalent compounds such as the lithium alkyls. Derivatives of any alkali metal where charge delocalization can occur over several carbon atoms (e. g. triphenylmethyl-sodium, lithium-benzyl) were also considered to be largely ionic in constitution. 

Irradiation of (triphenylmethyl)lithium in tetrahydrofuran containing bromobenzene or iodobenzene produced three major products tetraphenylmethane (TPM), bipheny-lyldiphenylmethane (BDM) and 2-(triphenylmethyl)tetrahydrofuran (TTF)687. Product... 

Acyclische und spirocyclische Pentaarylphosphorane erhalt man unter milden Reaktions-bedingungen durch Einwirkung von Aryl- bzw. Triphenylmethyl-lithium- oder -magne-sium-Verbindungen auf Tetraarylphosphoniumsalze23-25 ... 

However, it was not possible to obtain l-trityl-2-nitroimidazole by this method as, for example, also during the nitration of the lithium derivative of 1-tritylimida-zole by nitronium tetrafluoroborate [356], This is probably due to the elimination of the triphenylmethyl group during nitration. However, it was possible to obtain l-trityl-2-nitroimidazole by using propyl nitrate as nitrating agent [356], The product... 

Azoisobutyronitrile Cyclopropylmethyl 3-exo Cyclisation A-endo Cyclisation Collidine DEPO Diethylphosphine oxide DPT Density functional theory DTBP Di-tert-butyl peroxide EPHP AT-Ethylpiperidine hypophosphite PCI Functional group interconversions EiMPA Hexamethylphosphoramide EDA Lithium diisopropylamide MAP 4-Methoxyacetophenone PTOC AT-Hydroxypyridine thione TMM Trimethylenemethane trityl Triphenylmethyl... 

Tolbert and Martone have reported further on the photochemistry of triphenylmethyl-lithium in tetrahydrofuran, and a review of the photochemical activity of organic anions has been published. ... 

Diphenylcyclopropenecarboxylic acid gives the corresponding diphenylcyclopro-penyl cation using acetyl perchlorate however, the major product is durene when the tetrafluoroborate salt is used. With triphenylmethyl perchlorate in methylene chloride and lithium carbonate this acid is converted into l,2-diphenyl-3-triphenylmethylcyclopropenyl cation (15) (equation 7). 

The triphenylmethyl carbanion, the trityl anion, can be generated by the reaction of triphenylmethane with the very powerful base, n-butyllithium. The reaction generates the blood-red lithium triphenylmethide and butane. The triphenylmethyl anion reacts much as a Grignard reagent does. In the present experiment it reacts with carbon dioxide to give triphenylacetic acid after acidification. Avoid an excess of n-butyllithium on reaction with carbon dioxide, it gives the vile-smelling pentanoic acid. 

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