γ-lactonization of homopropargyl alcohols via an alkyne deprotonation/boronation/oxidation sequence has been developed. Oxidation of the generated alkynyl boronate affords the corresponding ketene intermediate, which is trapped by the adjacent hydroxy group to furnish the γ-lactone. We have optimized the conditions as well as examined the substrate scope and synthetic applications of this efficient one-pot
The chemistry of small-ring compounds. Part 51. Electron-transfer-initiated oxidation of some cyclopropylidene compounds
作者:A. Hofland、Th. J. de Boer
DOI:10.1002/recl.19871061103
日期:——
Cyclopropylidenecompounds of type 1 are found to quench the fluorescence of 9,10-dicyanoanthracene (DCA). Nevertheless photo-oxygenation, in the presence of DCA, leads under no circumstances to dioxetanes but (in ethanol) to a methoxy hydroperoxide 5, as tentatively shown in Scheme 2. This hydroperoxide undergoes acid rearrangement either to a lactone or to a cyclobutanone, depending on the reaction
Reaction of cycloalkanones with methyl 3-bromopropionate and Sml2 afforded formation of spiroanellated γ-lactones, pinacols and unprecedented 3-(1-hydroxycycloalkyl)-1-oxaspiro[n,m]alkan-2-ones.
Velzen, J. C. van; Tunen, W. C. J. van; Boer, Th. J. de, Recueil des Travaux Chimiques des Pays-Bas, 1986, vol. 105, # 7-8, p. 225 - 228
作者:Velzen, J. C. van、Tunen, W. C. J. van、Boer, Th. J. de
DOI:——
日期:——
Silicon in Synthesis. 10. The (Trimethylsilyl)allyl Anion: A .beta.-Acyl Anion Equivalent for the Conversion of Aldehydes and Ketones into .gamma.-Lactones