Synthesis of Enantiomerically Pure 1,2,3-Trisubstituted Cyclopropane Nucleosides Using Pd-Catalyzed Substitution via Directing Group-Mediated C(sp3)-H Activation as a Key Step.

A series of enantiomerically pure 1,2,3-trisubstituted cyclopropane nucleosides Ia-Id and IIa-IId of medicinal chemical interest was designed and synthesized. In the synthesis, a Pd-catalyzed substitution reaction via a directing group-mediated C(sp3)-H activation was effectively used to construct the 1,2,3-trisubstituted cyclopropane structure as a key step.