D/L selective re-binding of saccharide-imprinted [60]fullerene- bisadducts based on a saccharide-boronic acid interaction: Development of a molecular imprinting technique useful in a homogeneous system

The memory effect of the D-threitol- or L-threitol-imprinted [60]fullerene-bisadduct [((f)C)-4 or ((f)A)-4], which was obtained from the double addition reaction between [60]fullerene and D-threitol- or L-threitol- boronic acid 1:2 complex (D-1 or L-1), was discussed. In the competitive complexation with D-threitol and L-threitol, ((f)C)-4 or ((f)A)-4 diastereoselectively rebound with the original template, D-threitol or L- threitol, respectively, affording the corresponding 1:1 complex [((f)C)-3D or ((f)A)-3L]. The selectivities increased with lowering the complexation temperature; under the optimum conditions 48% diastereomeric excess was achieved.