Cellulose carbamates transcarbamoylation/transurethanization of methyl carbamates in superbase-acid conjugate ionic liquids.

A sustainable homogeneous transcarbamoylation/transurethanization protocol for cellulose modification with methyl -substituted carbamates was developed. The protocol utilizes the superbase ionic liquid [mTBNH][OAc], not only as a green reaction medium, but also as a promotor of the transformation. This approach allows to obtain different cellulose carbamates with controllable degrees of substitution.

Bicyclic guanidine superbase carboxylate salts for cellulose dissolution.

Bicyclic guanidines are utilized in organic synthesis as base catalysts or reagents. They also offer a platform for coordination chemistry, for example in CO activation, and their carboxylate salts offer an efficient media for cellulose dissolution. We have studied a series of bicyclic guanidines with varying ring sizes and with varying methyl substituents with a specific aim to find hydrolytically stable acetate salts for dissolution and processing of cellulose.