The regioselectivity of the addition of benzeneselenyl chloride to 7-azanorborn-5-ene-2-yl derivatives is controlled by the 2-substituent: new entry into 3-and 4-hydroxy-5-substituted prolines
The electrophilic addition of benzeneselenyl chloride to the alkene moiety of 7-azabicyclo[2.2.1]hept-5en-2-yl derivatives has been studied. With camphanates 8 and 9 N-Boc-5-endo-chloro-6-exo-phenylseleno-7-azanorborn-2-yl camphanates 10 and 11 are obtained with high regioselectivity due to a steric control. With N-Boc-7-azanorbor-5-en-2-one (2) the corresponding 6-endo-chloro-5-exo-phenylseleno derivative 15 is obtained in high yield due to a kinetic control attributed to the electron-releasing ability of the homoconjugated carbonyl group. Bicyclic adducts 10 and 11 and 15 are readily converted into 4-hydroxy-(14) and 3-hydroxy-5-substituted proline derivatives 19, respectively. (C) 2010 Elsevier Ltd. All rights reserved.
Keywords: 7-Azanorbornenes ; 7-Azabicyclo[2.2.1]heptanes ; Naked sugar ; Hydroxylated prolines ; Bulgecinine ; Homoconjugated Carbonyl Group ; Bulge-Inducing Activity ; Enantiomerically Pure ; Bacterial Metabolites ; Formal Synthesis ; Mytilus-Edulis ; E-Selectin ; Epibatidine ; Analogs ; Acid
Record created on 2011-12-16, modified on 2016-08-09