98361-29-6Relevant academic research and scientific papers
1,5-DICARBONYL COMPOUNDS A GENERAL PREPARATION METHOD
Duhamel, P.,Hennequin, L.,Poirier, J. M.,Tavel, G.,Vottero, C.
, p. 4777 - 4786 (2007/10/02)
In this report, a general method for the preparation of 1,5-dicarbonyl compounds and six membered ring annelation is described.This method involves the reaction of hemiacetal vinylogs 1 with enol ethers 2 or 3 in the presence of a Lewis acid.This reaction was successfully applied to the enol ethers of α and α,α'-hindered ketones such as 2,2,6-trimethyl cyclohexanone. α-Cyperone and 6-epi-α-cyperone were obtained using this process.
A Silyl Enol Ether Variation of the Robinson Annulation
Huffman, John W.,Potnis, Shailesh M.,Satish, Amruthur V.
, p. 4266 - 4270 (2007/10/02)
The Lewis acid catalyzed reaction of regioselectively generated silyl enol ethers with vinyl ketones has been explored as an alternative to the Robinson annulation sequence.Alkylation of the trimethylsilyl enol ethers of cyclohexanone, 2-methylcyclohexanone, and 2,3-dimethylcyclohexanone with ethyl vinyl ketone, 3-penten-2-one, and methyl vinyl ketone ethylene ketal gave a series of 1,5-diketones.Cyclization of the diketones affords 2-octalones in fair to good overall yield.This procedure has been used to prepare in good yield 5,10-dimethyl-Δ1(9)-2-octalone, an important intermediate for sesquiterpene synthesis, with a cis/trans ratio of 3 to 1.Alkylation of the trimethylsilyl enol ether of isobutyraldehyde with 3-penten-2-one, methyl vinyl ketone, and its ethylene ketal followed by cyclization affords 4,4,5-trimethyl- and 4,4-dimethyl-2-cyclohexen-1-one.This method has been employed in the synthesis of 5-(hydroxymethyl)-2,4,4-trimethyl-2-cyclohexen-1-one, a potential synthon for ring A of the taxane diterpenes.
A Reexamination of the Robinson Annelation of 2-Methylcyclohexanone with 3-Penten-2-one and 4-Phenyl-3-buten-2-one
Kikuchi, Mitsuko,Yoshikoshi, Akira
, p. 3420 - 3424 (2007/10/02)
The reported Robinson annelation of 2-methylcyclohexanone with 3-penten-2-one has been reexamined.In contrast to the previous result, it was found that the reaction product was not only obtained in a low yield, but also the solvent-depending stereoselecti
