Toward chiral polyhydroxylated dendrimers. Preparation and chiroptical properties

Four dendrimers (1b-4b) containing chiral vicinal diol-based subunits were prepared from their acetonide-protected precursors (1a-4a). The optical act ivity of these chiral dendritic structures was successfully modeled using s tructurally similar, low molecular weight model compounds. Using the [Phi]( d) values of the low molecular weight model compounds 5b-7b, we calculated [Phi](d) values for dendrimers 1b-4b that agree to within 4.5% of the obser ved values. Agreement between the optical activity of the model compounds a nd that of the dendrimers leads to the conclusion that the conformational e quilibria of the dendrimer subunits are not perturbed relative to those of the model compounds.