REGIOSELECTIVE ESTERIFICATION AND ETHERIF ICATION OF CELLULOSE AND CELLULOSE DERIVATIVES .1. PROBLEMS AND DESCRIPTION OF THE REACTION SYSTEMS

In this first of three separate contributions the preparation and reac tivity of cellulose intermediates are described. These derivatives are suitable for the synthesis of cellulose esters and ethers with a regi oselective distribution of substituents within the anhydroglucose unit . In case of corresponding 2,3,6-tri-O- and 6-O-silyl- and 6-O-tritylc elluloses the complete resp. selective introduction of protective or a ctivating groups succeeds during or after dissolution of the cellulose . In case of the formation and modification of cellulose nitrite a reg ioselectively controlled reactivity results in subsequent syntheses. C ellulose acetates regioselectively substituted at the O-6 position are accessible by controlled 2,3-deacetylation of cellulose triacetate us ing selected aliphatic amines.