Various (β-lactams are prepared from the corresponding β-amino acids under mild reaction conditions in high yields by employing 2-chloro-1-methylpyridinium iodide as a condensing reagent.
A NOVEL METHOD FOR THE SYNTHESIS OF β-LACTAMS BY MEANS OF PHASE TRANSFER SYSTEM
作者:Yutaka Watanabe、Teruaki Mukaiyama
DOI:10.1246/cl.1981.443
日期:1981.4.5
The reaction of β-amino acids with methanesulfonyl chloride in a chloroform-water bilayer system in the presence of 15 mol% of tetrabutylammonium hydrogen sulfate gives the corresponding β-lactams in good yields.
Conversion of .beta.-amino esters to .beta.-lactams via tin(II) amides
作者:Wei Bo Wang、Eric J. Roskamp
DOI:10.1021/ja00074a007
日期:1993.10
Addition of Sn[N(TMS)2]2 to beta-amino esters with sterically nondemanding substituents at C3 or on nitrogen gave beta-lactams in 76-100% yield. More sterically demanding beta-amino esters could be converted to beta-lactams in excellent yield using unsymmetrical tin(II) amide reagents which were prepared in situ. Optimal results for the in situ procedure involved addition of Sn[N(TMS)2]2 to a beta-amino ester, followed by addition of either pivalic acid or N-tert-butylacetamide.
KIM, SUNGGAK;YI, KYU-YANG;NAMKUNG, JA-YOUNG, HETEROCYCLES, 29,(1989) N, C. 1237-1240