Preparation of functionalised monobactams from pyridones
摘要:
A novel synthesis of functionalised monobactams in high isolated yields is described. The procedure involves photochemical cyclisation of commercially available 2-pyridones followed by ring-opening cross-metathesis. (C) 2009 Elsevier Ltd. All rights reserved.
Eight dienic nitrogen compounds were prepared starting from cyclobutene lactam 8. Dienes 12-15 were obtained by benzylation or acylation followed by methanolysis, hydrolysis or reduction. The unsubstituted lactam 8 provided diene 16. The latter was a precursor for the mono and biacylated products 17-19.
The Synthesis of Aza[n]ladderanes and Azahomo[n]ladderanes Containing β-Lactams at the Terminus
作者:Ronald Warrener、Richard Russell、Davor Margetic
DOI:10.1055/s-1997-697
日期:——
5-Azabicyclo[2.2.0]hex-2-en-6-one 1 undergoes [2Ï+2Ï] cycloaddition with dimethyl acetylene dicarboxylate (Ru-catalysed) to yield aza[3]ladderane 2 which is transformed to aza[5]ladderanes 4 and 5 on treatment with cyclobutadiene and to azahomo[5]ladderanes 10 and 11 on reaction with cyclopentadiene. The specifities of these cycloaddition reactions are in agreement with predictions made using ab initio calculations. Chlorosulfonylisocyanate addition is used to access azahomo[4]ladderane 14.
5-Azabicyclo[2.2.0]hex-2-en-6-one 1 与乙炔二羧酸二甲酯发生 [2Ï+2Ï] 环加成反应(Ru 催化),生成氮杂[3]梯烷 2,与环丁二烯处理后转化为氮杂[5]梯烷 4 和 5,与环戊二烯反应后转化为氮杂[5]梯烷 10 和 11。这些环加成反应的特性与利用 ab initio 计算得出的预测结果一致。氯磺酰异氰酸酯加成反应可用于获得氮杂二茂[4]梯烷 14。
Preparation of functionalised monobactams from pyridones
作者:Mauro F.A. Adamo、Paolo Disetti、Linda Piras
DOI:10.1016/j.tetlet.2009.03.045
日期:2009.7
A novel synthesis of functionalised monobactams in high isolated yields is described. The procedure involves photochemical cyclisation of commercially available 2-pyridones followed by ring-opening cross-metathesis. (C) 2009 Elsevier Ltd. All rights reserved.
A Short Stereoselective Preparation of Dienamides from Cyclobutene Compounds. Application in the Synthesis of a New Cyclohexene Nucleoside
作者:Noëlle Gauvry、François Huet
DOI:10.1021/jo001467v
日期:2001.1.1
from 2-hydroxypyridine by a photochemical electrocyclic reaction. The tert-butoxycarbonyl derivative 17 was prepared to facilitate nucleophilic attacks to the carbonyl group, and the subsequent thermal ring opening provided dienes 18-21. One of these (20) was used in the synthesis of the cyclohexene nucleoside 30. A Diels-Alderreaction between diene 20 and maleic anhydride provided the endo-cycloadduct