Asymmetric synthesis of β-lactams by chiral ester enolate - imine condensation
作者:Iwao Ojirna、Ivan I-Iabus
DOI:10.1016/s0040-4039(00)97603-2
日期:1990.1
Asymmetric cyclocondensation of N,N-bis(silyl)glycinates bearing chiral ester moieties with aldimines is found to proceed with extremely high enantioselectivity to give the corresponding chiral β-lactams in good to high yields. It is found that the E/Z-geometry of the chiral ester-enolate ts responsible for cis/trans stereochemistry of the β-lactam formed. Effects of various chiral auxiliaries in the
Synthesis of Novel N-Sulfonyl Monocyclic β-Lactams as Potential Antibacterial Agents
作者:Aliasghar Jarrahpour、Maaroof Zarei
DOI:10.3390/11010049
日期:——
New cis monocyclic β-lactams were synthesized by [2+2] Staudinger cycloaddition reactions of the imine (3,4-dimethoxybenzylidene)-(4-methoxyphenyl)- amine and ketenes derived from different acyl chlorides and Et3N. These monocyclic β-lactams were then cleaved by ceric ammonium nitrate (CAN) to give NH-monocyclic β-lactams, which in turn were converted to N-sulfonyl monocyclic β-lactams by treatment with four different sulfonyl chlorides in the presence of Et3N and 4,4-dimethyl- aminopyridine (DMAP).
Asymmetric Synthesis of β-Substituted α-Methyl-β-amino Esters by Mannich Reaction of (<i>S</i>,<i>S</i>)-(<i>+</i>)-Pseudoephedrine Acetamide Derived Enolate with Imines
作者:Jose L. Vicario、Dolores Badía、Luisa Carrillo
DOI:10.1021/ol0155384
日期:2001.3.1
[reaction: see text]. The reaction of an (S,S)-(+)-pseudoephedrine acetamide based enolate with several imines afforded smoothly and with full stereochemical control a series of beta-substituted alpha-methyl-beta-aminoamides that upon hydrolysis/esterification afforded the corresponding beta-aminoester derivatives in good yields and in almost enantiomerically pure form.
Electroreductive acylation of aromatic imines with acylimidazoles
作者:Naoki Kise、Shinji Morimoto
DOI:10.1016/j.tet.2007.11.106
日期:2008.2
The intermolecular reductive coupling of aromatic imines with acylimidazoles was effected by electroreduction in the presence of chlorotrimethylsilane and gave a-amino-a-aryl ketones. This method was also effective for the synthesis of alpha-amino-alpha-aryl esters using methoxycarbonylimidazole as an electrophile. (c) 2007 Elsevier Ltd. All rights reserved.
Kumar, Baldev; Kumar, Harish; Arora, Shivani, Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 1993, vol. 32, # 7, p. 779 - 782