Aromatic nucleophilic substitution in nonionic alkylglucoside micelles

The kinetics and mechanism of the aromatic nucleophilic substitution reaction of 2,4-dinitrochlorobenzene (DNCB) with OH- in nonionic sugar-derived micelles were investigated and compared with those for reaction in polyoxyethylene glycol surfactants. Hydroxyl groups on the sugar headgroups of micellized n-nonyl beta-D-glucopyranoside (C9G1), n-dodecyl beta-D-maltoside (C12G2), and n-dodecyl beta-D-maltotrioside (C12G3) are partially deprotonated by OH- and the alkoxide ions react with DNCB, forming an arene ether. Observation of more than one isosbestic point indicates that more than one intermediate ether is formed, largely at C3 or C4 with micellar stereocontrol. Over time the ethers react with OH- giving 2,4-dinitrophenoxide ion.