99377-03-4Relevant academic research and scientific papers
Rhodium-catalyzed intermolecular chelation controlled alkene and alkyne hydroacylation: Synthetic scope of β-S-substituted aldehyde substrates
Willis, Michael C.,Randell-Sly, Helen E.,Woodward, Robert L.,McNally, Steven J.,Currie, Gordon S.
, p. 5291 - 5297 (2006)
The use of β-S-substituted aldehydes in rhodium-catalyzed intermolecular hydroacylation reactions is reported. Aldehydes substituted with either sulfide or thioacetal groups undergo efficient hydroacylation with a variety of electron-poor alkenes, such as enoates, in Stetter-like processes and with both electron-poor and neutral alkynes. In general, the reactions with electron-poor alkenes demonstrate good selectivity for the linear regioisomer, and the reactions with alkynes provide enone products with excellent selectivity for the E-isomers. The scope of the process was shown to be broad, tolerating a variety of substitution patterns and functional groups on both reaction components. A novel CN-directing effect was shown to be responsible for reversing the regioselectivity in a number of alkyne hydroacylation reactions. Catalyst loadings as low as 0.1 mol % were achievable.
2-Alkenyl-Substituted Methyl 2-Siloxycyclopropanecarboxylates as Masked Vinyl Ketones: Efficient Syntheses of Highly Functionalized Michael Adducts.
Grimm, Erich L.,Zschiesche, Ruth,Reissig, Hans-Ulrich
, p. 5543 - 5545 (2007/10/02)
2-Alkenyl-substituted methyl 2-siloxycyclopropanecarboxylates 3a, 3b, and 6 - easily available from the corresponding silyl enol ether - react with a variety of O-, N-, S-, and C-nucleophiles under mild acidic or basic conditions providing polyfunctionalized products 7-19 in good to excellent yields via 1,4-addition to vinyl ketones formed in situ.Due to the versatility of the nitro group, nitroalakne, adducts 15-19 are of special interest for further transformations.
