First Synthesis of 3‐O‐Functionalized Cellulose Ethers via 2,6‐Di‐O‐Protected Silyl Cellulose

The present paper describes the synthesis of 2,6‐di‐O‐thexyldimethylsilyl cellulose as a novel 2,6‐di‐O‐protected cellulose derivative. This material was obtained by reacting cellulose in N,N‐dimethylacetamide/LiCl solution with thexyldimethylchlorosilane and imidazole for 24 h at 100°C. In a typical subsequent reaction the residual OH‐group in position 3 could be completely etherified without loss of any protecting groups. Treatment with tetrabutylammonium fluoride leads to the novel compounds 3‐O‐allyl and 3‐O‐methyl cellulose. The structures of all polymers are revealed by means of one‐ (¹H and ¹³C) and two‐dimensional (COSY and HMQC) NMR techniques.