2-Chloromethyl-4-nitrophenyl esters

The preparation of phosphate esters has been reviewed and full details have appeared of the use of 2-chloromethyl-4-nitrophenyl esters (reported last year) in the synthesis of monoesters and mixed dialkyl esters of phosphoric acid. 

Materials. Crosslinked polystyrene beads were purchased from Bio-Rad Laboratories and were dried under vacuo at 40 C. Merrifield resin (chloromethyl group content 0.9 meq/g) was purchased from Pierce Chemical Co. A series of 3-nitro-4-acyloxy-benzoic acids ( ) were prepared by methods described in the literature. The long-chain p-nitrophenyl ester substrates were purchased from Sigma Chemical Co. p-Nitrophenyl acetate was a product of Pierce Chemical Co. and sublimed in vacuo before being used. Polystyrene (average MW 22,000) was purchased from Aldrich Chemical Co. 

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