Triphosgene: a versatile reagent for the synthesis of azetidin-2-ones
摘要:
An efficient use of triphosgene, as an acid activator, for the synthesis of substituted azetidin-2-ones via ketene-imine cyclo-addition reaction using various acids and imines have been described. (C) 2002 Elsevier Science Ltd. All rights reserved.
4,4-Bis(methylthio)azetidin-2-ones as synthons of 1,2- and 1,3-dicarbonyl systems
作者:Monika I. Konaklieva、Lita S. Suwandi、Maya Kostova、Jeffrey Deschamps
DOI:10.1016/j.tetlet.2011.02.046
日期:2011.4
The importance of beta-lactams as synthetic building blocks has been widely recognized in organic synthesis due to possible ring cleavage at any of the four single bonds of the beta-lactam ring. We now report reactions involving breaking of the N1-C4 bond in differently substituted at C3 4,4-bis(methylthio)azetidin-2-ones, leading to formation of 1,2- and 1,3-dicarbonyl systems. (C) 2011 Elsevier Ltd. All rights reserved.
SHARMA, S. D.;MEHRA, USHA;KHURANA, J. P. S.;PANDHI, S. B., SYNTHESIS,(1987) N 11, 990-992
作者:SHARMA, S. D.、MEHRA, USHA、KHURANA, J. P. S.、PANDHI, S. B.
DOI:——
日期:——
Triphosgene: a versatile reagent for the synthesis of azetidin-2-ones
An efficient use of triphosgene, as an acid activator, for the synthesis of substituted azetidin-2-ones via ketene-imine cyclo-addition reaction using various acids and imines have been described. (C) 2002 Elsevier Science Ltd. All rights reserved.
Synthesis of 4-Unsubstituted β-Lactams<i>via</i>Dithiocarbonimidates
作者:S. D. Sharma、Usha Mehra、J. P. S. Khurana、S. B. Pandhi
DOI:10.1055/s-1987-28144
日期:——
Cycloaddition of dithiocarbonimidate 1 to the ketene generated in situ from phenoxyacetylchloride in the presence of triethylamine affords the 4-dithioalkyl-2-azetidinones 2 in good yields. Facile conversion of 2 to the 4-unsubstituted ß-lactams 3 can be accomplished by desulfurization with Raney-Nickel. Formation of several interesting products during attempts to bring a carbonyl function at C-4 in 2 has also been described.