Arsonium ylides hydrolysis

By far the most important reactions of ylides are those of the Wittig type, especially those with carbonyl compounds, and they will be dealt with first other reactions of this sort are those with other C = X functions and with nitroso-compounds. Other carbanionic reactions are then considered and a final section deals with the formation of cyclic compounds from arsonium ylides. Hydrolysis has already been discussion in Section III.B. 

In this case the ylide was not isolated but allowed to react with ben2ophenone to give, after hydrolysis with hydrochloric acid, 1,1-diphenylethylene, diphenylacetaldehyde, and triphenylarsine (160). An excellent method for preparing arsonium ylides involves the reaction between a stable dia2o compound and triphenylarsine in the presence of a copper catalyst such as bis(acetylacetonato)copper(II) (161). Rather than a dia2o compound, an iodonium yhde can be used again a copper catalyst is necessary for an optimum yield of product. An example of the use of a dia2o compound is shown in the formulation of triphenyl arsonium 2,3,4-triphenylcyclopentadienyLide [29629-32-17, C H As ... 

It has been speculated" that, by analogy with the mechanism proposed for the extensively studied hydrolysis of phosphonium ylides, the steps involved in hydrolysis are protonation, followed by formation of a pentacovalent arsenic species and finally loss of a carbanion (equation 5). Presumably for arsonium ylides, as for phosphonium ylides, the... 

Arsonium ylides react with fluoroalkenes the isolated products, after hydrolysis, are disubstituted arsonium ylidese.g. equation 15. In some, but not all cases, the... 

Arsinimines 35 are the nitrogen analogues of arsonium ylides. They appear to be more resistant to hydrolysis than are ylides, for even the simple non-stabilized example (35,... 

Triaryl-phosphonium or -arsonium fluorenylides are markedly more stable to hydrolysis than their trialkyl analogues [171-174], This can again be attributed to the more polar character of the latter ylides [173], In keeping with this the trialkyl derivatives are also more reactive in Wittig reactions than are their triphenyl analogues [172,173,176,177],... 

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