Michael Additions in Aqueous Media: “On-Water” and “In-Water” Processes from α-Nitro Ketones and Their Anions
作者:Giorgio Giorgi、Pilar López-Alvarado、Sonia Miranda、Jean Rodriguez、J. Carlos Menéndez
DOI:10.1002/ejoc.201201431
日期:2013.3
A variety of α,β-unsaturatedaldehydes and ketones gave very high-yielding Michael addition reactions with α-nitrocycloalkanones in water, at room temperature without added catalyst. These can be considered as one of the very few “on-water” Michael reactions known in the literature, because they took place in suspension or emulsion and at increased speed relative to the same transformations performed
Synthesen Makrocyclischer Lactone durch Ringerweiterung. Vorläufige Mitteilung
作者:Kalina Kostova、Manfred Hesse
DOI:10.1002/hlca.19830660303
日期:1983.5.5
Syntheses of Macrocyclic Lactones by Ring Enlargement Reaction
环扩大反应合成大环内酯
Synthesen makrocyclischer Lactone durch Ringerweiterung Herstellung von (±)-Phoracantholid I, (±)-Dihydrorecifeiolid und (±)-15-Hexadecanolid
作者:Kalina Kostava、Manfred Hesse
DOI:10.1002/hlca.19840670708
日期:1984.11.7
Syntheses of Macrocyclic Lactones by Ring Enlargement Reaction Reaction. Preparation of (±)-Phoracantholide I, (±)-Dihydrorecifeiolide and (±)-15-Hexadecanolide
The reaction of α-nitro ketones to the corresponding α-hydroxy ketones under basic aqueous conditions, a novel transformation, was studied. The investigation revealed that the reaction is only possible with α-nitro ketones that are CH-acidic in the α′-position and readily deprotonated under the reaction conditions. The NO2/OH exchange was established to proceed with retention of configuration at the
Synthesis of 14-Membered Lactones from Cyclooctanone
作者:Tetsuya Aono、Manfred Hesse
DOI:10.1002/hlca.19840670604
日期:1984.9.26
As shown in the Scheme, 3-(1-nitro-2-oxocyclooctyl)propanal (1) prepared earlier from cyclooctanone was converted into the 14-membered lactones 6 and 7. The aldehyde 1 was submitted to allylation to give 2 using allyltitnium or allylsilicon reagents. After lactonizatrion and transformation of the C,C-double bond to an alcohol, 4 was translactonized under acidic conditions to form 5, from which 6 and