Potassium triphenylmethide

Alkylation of disubstituted acetic esters has become an important new route to trisubstituted acetic acids and their derivatives. Sodium tri-phenylmethide or potassium triphenylmethide is used to convert the ester to its enolate ion, which, in turn, is allowed to react with an alkyl iodide to form the trialkylated ester. The yields are in the range of 42-61%. Potassium hydroxide in acetal solvents serves as basic reagent in the alkylation of certain esters by reactive halides. An interesting preparation of diethyl tetramethylsuccinate involves alkylation of ethyl isobutyrate with ethyl a-bromoisobutyrate. The yield is 30%. ... 

When a trace of KNH2 is added to a solution of chlorobenzene and potassium triphenylmethide, (CeH5)3C K, in liquid ammonia, a rapid reaction takes place to yield a product of formula C2sH2o- What is the product What is the role of KNH2, and why is it needed ... 

Potassium nitronates, 950 Potassium nitrosodisulfonate, 940-942 Potassium permanganate, 713, 942-952 Potassium peroxymonosulfate. 952 Potassium persulfate, 952-954 silver-catalyzed, 954 Potassium phenoxide, 300 Potassium-sodium tartrate, 36 Potassium thiocyanate, 199, 378, 954 Potassium thiolacetate, 356,955-956 Potassium triacetylosmate, 955 Potassium triphenylmethide, see Triphenyl-methyl potassium Prednisolone, 997 21-acetate, 604... 

The conversion of the potassium to potassium triphenylmethide is assumed to be quantitative, producing 0.2 mol of the reagent. Carbonation of the reagent gives a 91 yield (based on either triphenylmethane or potassium) of triphenylacetic acid, mp 263-265°. 

Potassium triethylmethoxide (Potassium t-heptoxide). (C2H5)3CO K+[l, 956, before Potassium triphenylmethide]. Mol. wt. 154.29. 

Tritylpotassium (Potassium triphenylmethide), (C6H5)3CK. This strong base can be generated by addition of triphenylmethane dissolved in DME to potassium hydride which has been treated with a small quantity of DNISO. It has also been generated from triphenylmethane and potassium hydride in the presence of a crown ether. ... 

Propose an explanation for the observation that potassium amide enhances the rate of formation of tetraphenylmethane in the reaction of chlorobenzene with potassium triphenylmethide in liquid ammonia. 

Triphenylmethyl sodium and triphenylmethyl potassium conduct in liquid ammonia although they slowly react with that solvent.887 888 When the liquid ammonia is allowed to evaporate from a solution of triphenylmethyl sodium in ammonia, the residue is a colorless mixture of sodamide and triphenylmethane. The sodium-tin and sodium-germanium compounds analogous to sodium triphenylmethide are also strong electrolytes in liquid ammonia. Sodium acetylide in liquid ammonia is dissociated to about the same extent as sodium acetate in water.889... 

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