Capping α‐Cyclodextrin with Cyclotriveratrylene by Triple Disulfide‐Bridge Formation. Issue 13 (13th March 2013)

• Record Type: Journal Article
• Authors: Brégier, Frédérique; Lavalle, Juliette; Chambron, Jean‐Claude
• Is Part Of: European journal of organic chemistry. Issue 13(2013)
• Page Start: 2666
• Page End: 2671
• Publication Date: 2013-03-13
• Subjects: Supramolecular chemistry -- ­Cavitands -- Cyclodextrins -- Hemicrypt­ophane -- Sulfur; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.201201729
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract: Disulfide‐bond formation is an expeditious coupling reaction to make macropolycyclic symmetrical receptors. It is used here for the preparation of unsymmetrical cavitands based on α‐cyclodextrin (α‐CDX) and cyclotriveratrylene (CTV) analogues. Accordingly, diastereomeric hemicryptophanes2a and2b were obtained in 11 % isolated yield by the iodine oxidation of a 1:1 mixture of racemic cyclotrithiophenolene (3 ) and the C 3 ‐symmetric trithiol derivative of permethylated α‐cyclodextrin (PM α‐CDX)4 . Remarkably, the target hemicryptophanes were obtained in a 5:3 diastereomeric ratio. The reaction produced mainly (34 %) a singly disulfide‐bridged PM α‐CDX dimer7, however no traces of triply disulfide‐bridged head‐to‐head PM α‐CDX dimer were detected. In addition, the formation of the known S ‐cryptophane‐0.0.0 was observed. Abstract : Hemicryptophanes based on permethylated ‐cyclodextrin (PM ‐CDX) were obtained as a diastereomeric mixture in a 5:3 ratio and 11 % yield by reacting a C 3 ‐symmetric trithiol PM ‐CDX derivative with the known chiral cyclotrithiophenolene under conditions (I2 /KI, Et3 N) that promote disulfide‐bridge formation.