The layered double hydroxides [LiAl2(OH)6]X.H2O (X = Cl-, OH-) exhibit facile ion-exchange intercalation chem. in which the inter-lamellar anions can be exchanged for a wide range of inorg. and org. anions in both aq. and non-aq. media. In addn., these materials displays the unique ability to selectively intercalate specific isomers of org. carboxylates and sulfonates from complex mixts. For example, the dicarboxylate anions 1,4-benzenedicarboxylate and fumarate are selectively intercalated into [LiAl2(OH)6]Cl.H2O from an equimolar molar mixts. of the 1,2- 1,3- and 1,4- benzenedicarboxylate and fumarate and maleate isomers resp. We can also affect which isomer is selectively intercalated by controlling the conditions of the reaction. The intercalated anions can be quant. recovered from the solid, and so new opportunities in recyclable chromatog.-style sepn. procedures are envisaged. [on SciFinder(R)]
