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A series of spacer-modified polystyrene-supported hydroxamic esters and hydroxamic dithiocarbonic anhydrides were prepared starting from divinyl benzene and ethyleneglycol dimethacrylate crosslinked polystyrene resins through multistage polymer-analogous reactions. Acyl transfer reactions using these polymer-supported hydroxamic acylating agents containing spacer arms of various lengths were carried out. The investigation revealed a sharp increase in reactivity as the length of the spacer arm was increased from zero methylene spacer to five methylene spacers. Investigations were also carried out to correlate the extent of acyl transfer with the nature and degree of crosslinking and the relative polarity of the polymer network. It was found that the extent of functionalization in each of the polymer analogous reactions and the extent of acylation reaction decreased with an increase in the degree of crosslinking.

Polystyrene-supported hydroxamic dithiocarbonicanhydrides were developed as a new class of regenerable solid phase reagents for acylating amino groups selectively. The reagent was prepared from crosslinked polystyrene support by a series of polymer analogous reactions. The crosslinking agents used were divinylbenzene (DVB) and ethyleneglycol dimethacrylate (EGDMA). The reagents were found to transfer their acyl groups to amines in solution at room temperature, yielding a solution of the corresponding amides. The influence of solvent, temperature, molar ratio and duration of reaction were studied to find out the optimum conditions. The spent reagent can be regenerated several times by a simple reaction, without significant loss in activity.

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