Acetic anhydride acetyl phosphate preparation with

Hydroxy-l,2-benziodoxole-3(l//)-one (104) is commercially available or can be easily prepared by direct oxidation of 2-iodobenzoic acid or by basic hydrolysis of 2-(dichloroiodo)benzoic acid [232,233,274]. A more recent preparative procedure for 104 involves the oxidation of 2-iodobenzoic acid with acetyl nitrate in acetic anhydride at room temperature followed by aqueous work-up [275]. In the 1980s benziodoxole 104 and other hydroxybenziodoxoles attracted considerable research interest due to their excellent catalytic activity in the cleavage of toxic phosphates and reactive esters. This activity is explained by a pronounced O-nucleophilicity of the benziodoxole anion 105 due to the a-effect [234,272,276]. Spectroscopic and kinetic mechanistic studies indicate that the highly unstable iodoxole derivatives, such as the phosphate 107, are reactive intermediates in catalytic cleavage of phosphates, as shown for the catalytic hydrolysis of a typical substrate 106 (Scheme 2.39) [277-279]. This mechanism was proved by the synthesis and reactivity studies of the phosphate intermediate 107. 

Compound (1) is prepared by reacting 4-hydroxybenzaldehyde with 6-chloro-1-hexanol in methanol for 24 h at 70°C, and then alcohol protects with acetic anhydride in triethylamine to produce compound (2). 4-(Trifluoromethyl)benzyl bromide is reacted with triethylphosphite to produce phosphate (4). The aldehyde and phosphonate are reacted with NaH in THF to form a stilbene moiety, and then deprotection of the acetyl group generates a hydroxyl group. The monomer is obtained by reacting compound (5) and methacryloyl chloride in triethylamine at... 

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