Asymmetric Synthesis of (-)-Pterocarine and (-)-Galeon via Chiral Phase Transfer-Catalyzed Atropselective Formation of Diarylether Cyclophane Skeleton.

Pterocarine and galeon are typical examples of diarylether heptanoids (DAEHs) with planar chirality due to the strictly constrained conformations in their molecular skeletons. The characterized oxa[1,7]metapara-cyclophane motifs in DAEHs impose great challenges for their enantioselective synthesis. The asymmetric syntheses of (-)-pterocarine and (-)-galeon are demonstrated by employing a chiral phase transfer-catalyzed highly enantioselective SNAr cyclization as the key step for the formation of a diarylether cyclophane skeleton.