Chiral ion-pair organocatalyst promotes highly enantioselective 3-exo iodo-cycloetherification of allyl alcoholsElectronic supplementary information (ESI) available: Experimental procedures and characterization for all new compounds. CCDC 1023013 and 1028455. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5sc02485d

By designing a novel chiral ion-pair organocatalyst composed of chiral phosphate and DABCO-derived quaternary ammonium, highly enantioselective 3- exo iodo-cycloetherification of allyl alcohols was achieved using NIS as a halogen source. Based on this reaction, one-pot asymmetric 3- exo iodo-cycloetherification/Wagner-Meerwein rearrangement of allyl alcohols en route to enantioenriched 2-iodomethyl-2-aryl cycloalkanones was subsequently developed. Due to the participation of adjacent iodine, the Wagner-Meerwein rearrangement of 2-iodomethyl-2-aryl epoxide proceeds with unusual retention of stereoconfiguration. Enantioselective 3- exo iodo-cycloetherification of allyl alcohols was realized by employing a novel ion-pair organocatalyst.