Derivatives of arsabenzene possessing a functional group

Alkylation of 4-hydroxyarsabenzene with methyl or ethyl iodide gives the 1-alky1-4-one (p.37 ), but with propyl iodide a trace of 4-propoxyarsabenzene is also obtained and with ethyl and propyl bromide mixtures of the corresponding 1-alkyl--4-ones and alkoxyarsabenzenes are formed (Markl and Rampal, Tetrahedron Letters, 1976, 4143). The acetylation of 1--arylarsacyclohexa-2,5-dien-4-one (6) results in a dienone--phenol type of rearrangement to yield 4-acetoxy-2-aryl-arsabenzene (7), which on hydrolysis affords the 2-ary1-4--hydroxyarsabenzene (8) (Markl and Rampal, ibid,y 1977, 3449). 

The reaction between 2-ary1-4-hydroxyarsabenzene (8 Ar= CgHj, 4-MeC H ) and phenyl radicals gives the ketone (9), which on acetylation yields the 4-acetoxy-2-aryl-6--phenylarsabenzene (10). Hydrolysis of (10) affords a product, which in ethanol and chloroform appears to contain both tautomers (11) and (12) (Markl and Rampal, ibid., 1978, 1471). 

The oxime of 1-phenylarsacyclohexa-2,5-dien-4-one (13) on lx)iling with acetic anhydride rearranges to give the diacetyl derivative of 4-amino-2-phenylarsabenzene (an arsaaniline derivative) (14) (Markl and Rampal, Tetrahedron Letters, 1978, 1175). 

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