Iodine Monochloride-Amine Complexes: An Experimental and Computational Approach to New Chiral Electrophiles

• Published in: Chemistry : a European journal Vol. 11; no. 19; pp. 5777 - 5785
• Main Authors: Haas, Jürgen, Bissmire, Stewart, Wirth, Thomas
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 19.09.2005; WILEY‐VCH Verlag; Wiley
• Subjects: Chemistry; Chemistry, Multidisciplinary; computer chemistry; electrophiles; iodine; iodolactonization; Physical Sciences; Science & Technology; stereoselective synthesis; CONSTANTS; ICL; computer chemistry; stereoselective synthesis; CHEMISTRY; iodine; iodolactonization; CHARGE-TRANSFER; CYCLIZATION; electrophiles
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.200500507

Lactonizations are important steps in many synthetic sequences. Substrate‐controlled reactions that use chiral auxiliaries or chiral alkenes have already been studied in depth. This study focuses on stereoselective reagent‐controlled iodolactonizations, by application of a new method that uses complexes of iodine monochloride and various donor molecules. (R)‐1,2,3,4‐Tetrahydro‐1‐naphthylamine and other amines with similar structures were found to be efficient in the iodocyclization of 4‐aryl‐4‐pentenoic acids. Calculations were performed on complexes of (R)‐1,2,3,4‐tetrahydro‐1‐naphthylamine with XCl (X=I, H) to identify possible reactive species in these iodocyclizations. Calculations were carried out at various levels of theory, including B3 LYP/6‐31+G (d,p) by using a modified SDD basis set for iodine. New chiral electrophiles were used for stereoselective iodocyclizations. Amine–ICl complexes (see figure) as efficient reagents for this reaction were analyzed from an experimental and theoretical perspective.