The asymmetric synthesis of 2,3-benzocarbapenems by intramolecular aryl radical cyclizations
作者:Benito Alcaide、Angel M. Moreno、Alberto Rodríguez-Vicente、Miguel A. Sierra
DOI:10.1016/0957-4166(96)00271-6
日期:1996.8
Racemic and enantiomerically pure 2,3-benzocarbapenems 1 are obtained in good yields by the tin-mediated, intramolecular aryl radicalcyclizations of the readily available 4-alkenyl-N-(2-halogenophenyl)-β-lactams 2.
Novel and effective routes to optically pure amino acids, dipeptides, and their derivatives viaβ-lactams obtained through asymmetric cycloaddition
作者:Iwao Ojima、Hauh-Jyun C. Chen
DOI:10.1039/c39870000625
日期:——
Opticallypuredipeptides bearing aromatic aminoacid residues were synthesized via homochiral (opticallypure)β-lactams which were obtainedthroughasymmetriccycloadditions of homochiral ketenes to homochiral imines.
Sequential and cascade ketene-imine [2+2]-cycloaddition-palladium catalysed cyclisation reactions occur in good yield. Racemic and homochiral examples incorporating a range of aromatic and heteroaromatic rings are reported.
Ojima, Iwao; Shimizu, Nobuko; Qiu, Xiaogang, Bulletin de la Societe Chimique de France, 1987, # 5, p. 649 - 658