Acylation of 6-O-Functionalized Cellulose Ethers with Diphenylketene

An environmentally friendly acylation reaction of 2-methylnaphthalene in solvent-free condition in a micro-channel reactor

“…In the acylation reaction of aromatic compounds using carboxylic acids, a mixture of graphite and p-toluenesulfonic acid was shown to be the best catalyst for the reaction. Carboxylic acids are not only used as a green acylating agent, but also as a solvent in this reaction [14]. The acylation of anisole with PC using MoO 4 (AlCl 2 ) 2 as the catalyst, in this reaction PC is the main reaction solvent [15].…”

A new protection group strategy for cellulose in an ionic liquid: simultaneous protection of two sites to yield 2,6-di-O-substituted mono-p-methoxytrityl cellulose

“…These tailored derivatives can be used as components or additives in industrial products such as adhesives, films, membranes and fibres. 1 However, the poor solubility of cellulose in common organic solvents and water has held back the development of efficient uses for cellulose. Recently, it has been shown that ionic liquids can dissolve cellulose, and further provide an inert and homogeneous reaction media for this macromolecule.…”

“…1,4 However, when selective modification of only one of the secondary OH groups (either C2-OH or C3-OH) is desired, the above-mentioned strategy has to be changed in such a way that the introduced PG has to be attached not only at the C-6 position, but also at the C-2 position, leaving C3-OH available for further modification. 1,5 The reason for the successful protection only at C2-OH, additionally to C-6, is due to the reactivity differences between C2-OH and C3-OH, which is typically in the order of C2-OH > C3-OH, 6 and also, in this case, the choice of the PG is important. Herein, it is shown that the p-methoxytrityl group can be used as a PG, providing the reaction is carried out in an ionic liquid.…”

“…The pattern of substitution was initially investigated with 1 H-13 C HMBC, despite several trials, we were unable to record a good quality HMBC spectrum due to the high molecular weight of the derivative. Therefore, 2D HSQC (Fig.…”

Regioselective Dendritic Functionalization of Cellulose

“…The properties of the cellulose derivatives not only depend on the nature of the substituents but also on the position of substitution and the distribution of functionality along the cellulose chain. [7][8][9][10][11][12] Using cellulose as the chiral polymeric core, we herein describe its dendronization specifically at the C-6 primary hydroxyl moiety without the cumbersome protectiondeprotection procedures that are generally used in carbohydrate functionalization.…”