Iodocarbocyclization and Iodoaminocyclization Reactions Mediated by a Metallic Reagent

All articles of this category We have developed new iodine-mediated carbocyclization and aminocyclization reactions through activation of intramolecular carbon or amide nucleophiles by metallic reagents. In the presence of I 2 and Ti(OR) 4 or TiCl 4 -Et 3 N, iodocarbocyclization of various active methine compounds having alkenyl or alkynyl groups proceeded in a highly stereospecific manner to give iodocyclo-alkanes or -alkenes in good yields. The present reaction can be also applied to asymmetric catalytic reation; that is, the reaction of 4-alkenylmalonate derivatives with Ti(TADDOLate) 2 catalyst gave iodoalkylcyclopentanes with excellent enantioselectivity (> 95%ee). Furthermore, iodoaminocyclization of unsaturated amide derivatives with an ambident nucleophilic center and iodoaziridination of N -allylic tosylamides, featuring regocontrol and an activation of an amide nucleophile by a basic metallic reagent, were also established. iodocarbocyclization - iodoaminocyclization - iodine - metallic reagent - catalytic asymmetric reaction