Hydroxyl groups modification with anhydrides

As mentioned previously, the C-3 hydroxyl group can be readily acylated with a wide variety of anhydrides and acid chlorides.30 Modification on this site of BA 1 and dihydro-BA 3 in our laboratory afforded a group of C-3 ester derivatives 7-22 (Table 13.1). 

During the chemical modification of wood with acetic anhydride (Scheme 9.4.8), the reaction takes place with the cell wall polymeric hydroxyl groups to form ester bonds. Acetic acid is produced as by-product. 

In this process polyol, dibasic acid and fatty acids are made to react simultaneously at a temperature of 220-260°C until the desired polyester is obtained. In this process, fatty acids compete with the phthalic anhydride and the phthalate half ester for the available hydroxyl groups. In a special modification of the fatty acid process developed by Kraft, the dibasic acid... 

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