Reagents for hydroxy compounds

Among the derivatization methods for hydroxyl groups, esterification with benzoyl chloride and its analogues 

Recently, Bayliss et al. [132] described the synthesis of anthracene-9-carbonyl chloride and its aplications as a label for fluorescence and UV absorbance detection of hydroxy compounds. The preparation and properties of esters of short-chain alcohols, diols, trichothecene mycotoxins and sterols were investigated. Anthracene-9-carbonyl chloride was prepared from commercial anthracene-9-carboxylic acid. Derivatization was carried out in acetonitrile free from water or active hydrogen compounds. The reaction rate was dejjendent on the structure of the alcohol. The derivatization of diethylene glycol was complete at ambient temp erature within 10 min (0.25 M reagent) or 30 min (0.1 M reagent) without a catalyst, but required 1 h for diolesteroL testosterone and the trichothecene T-2 toxin. For sterically hindered alcohols such as t-butanol and 17a-methyl-testosterone, more than 10 h, or refluxing for 1 h, was needed to complete the reaction. The derivatives had absorption maxima at 250 run. Both normal and reversed phase HPLC were applied to the separation of the derivatives. 

Bjorkqvist and Toivonen developed a procedure for derivatizing 2-ethylhexanol and other aliphatic alcohols 

Phenyldimethylsilyl chloride has been introduced as a reagent for labelling alditols and mono- and di-sacdtarides [135]. The derivatization was carried out in N,N-dimethyl-formamide. Imidazole solution (200 fi, 0.33 g ml ) was added to a solution of the carbohydrate ( 10mg). The mixture was then heated at 100 C for 1 h. After 

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