Arsenic trichloride trimethyl

Arsenocholine was synthesized from arsenic trichloride, producing first trimethylarsine by addition of MeLi, followed by conversion of the trimethyl-arsine into arsenocholine by addition of bromoethanol. Arsenobetaine was prepared from trimethylarsine (synthesized from commercial arsenic trichloride). 

The unknown compound tri-t-butyl arsenate has now been produced by transesterification of trimethyl arsenate with a large excess of dry t-butyl alcohol, but neither transesterification nor other conventional approaches gave the interesting, sterically hindered arsenite (Ph3CO)3As. The method successfully used was the reaction between arsenic trichloride and Ph3CONa in ether. 

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