In this paper

the derivatizing and non-derivatizing organic solvents for cellulose with special accentuation of dipolar-aprotic

O-basic solvent systems

are surveyed and the present state of knowledge on homogeneous acylation

alkylation and graft polymerization of cellulose in both categories of solvents is reviewed briefly. Recent results of the authors' work are then presented on the acylation of cellulose to anionic esters (sulphate and phosphate)

especially in the derivatizing solvent system "N

2

O

4

/DMF". Finally

the advantages and the shortcomings of homogeneous cellulose derivatization inthe new organic solvents ' are considered in a general discussion

accentuating the possible control of regioselectivity of substitution and the important role of the steps of after-treatment in determining product properties.