Synthesis of functionalized pyrrolidines from N-(benzylidene)- and N(alkylidene)-homoallylamines
摘要:
N-(Benzylidene)- and N-(alkylidene)-homoallylamines are cyclised by electrophiles, e,g. bromine or phenylselenenyl bromide, and by subsequent reduction to the corresponding 3-functionalised pyrrolidines; the stereochemistry was investigated, and reductive removal of the 3(or 4)-bromo- and 3(or 4)-phenylseleno-substituents was accomplished.
Synthesis of azetidines by electrophilic selenium-induced cyclization of homoallylic benzylamines
摘要:
Homoallyl benzylamines, prepared by allylation of the corresponding N-benzylimines, have been subjected to a selenium-induced cyclization under various conditions. At room temperature, the 4-exo and the 5-endo modes are competitive. In acetonitrile, the azetidine has been isolated as the major cyclization product, especially for homoallylamines derived from ketimines. With an excess of selenium reagent, 3-halopyrrolidines have been obtained. (C) 1997 Published by Elsevier Science Ltd.