Grignard reagents arsenic compounds

As exemplified in the sections indicated, these compounds show most of the typical reactions of Grignard reagents and alkyllithiums. Thus, pyridyllithiums and their benzo analogues allow the introduction of other metals, and non-metals, on to the ring, such as mercury, boron, phosphorus, tin and arsenic (Scheme 74) (see also Section 3.2.3.10.2.v). 

Reactions of Grignard reagents or organolithium compounds with arsenic halides, usually chlorides, have been one of the most frequently used method for the preparation of triorganoarsenic compounds. A wide variety of triorganoarsenic(III) compounds have been prepared as shown in equations 1 , 2 , 3 , 4 , 5 , 6 , 7 and 8 . 

Various alkyl and aryl substituted pentaorganoarsenic compounds are known - . Most of these have been synthesized by transmetallation from Grignard reagents or organo-lithium reagents to arsenic centers. 

In the reaction with halides of the less electropositive metals such as mercury,79 arsenic,80- 81 antimony,82 and indium,83 a stannane provides nucleophilic hydrogen and gives the new metal hydride (equation 15-27). Free radical inhibitors may be added to repress radical reaction of vinyl reactants. The preparation of vinylmercury hydride by this route involves the unusual use of tributyltin chloride as a solvent (equation 15-28).79 On the other hand, in the reactions of tributyltin hydride with Grignard reagents, RMgX, the hydrogen behaves as an electrophile towards R, and the Sn-Mg bonded compounds are formed.84... 

AS2O3 with the Grignard reagent from 1-naphthyl bromide followed by deeom-position with hydrochlorie aeid. The resolution into optically active isomers of the arsenic(ni) compounds (115) as hydrogen tartrates and the arsonium salts... 

The most convenient method, and thus that most often used, is treatment of arsenic halides with alkyl- or aryl-Grignard reagents or organolithium compounds.486,487... 

This type of compound is prepared by reacting arsenic hydrides with Grignard reagents, or in one case with ethylzinc iodide 212). 

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