Phosphine-Catalyzed Cycloadditions of Allenic Ketones: New Substrates for Nucleophilic Catalysis
作者:Debra J. Wallace、Rachel L. Sidda、Robert A. Reamer
DOI:10.1021/jo062170l
日期:2007.2.1
reactions of allenicketones have been studied, extending the scope of these processes from the more widely used 2,3-butadienoates to allow access to a number of synthetically useful products. Reaction of allenyl methyl ketone 4 with exo-enones afforded spirocyclic compounds in good regioselectivity and promising enantioselectivity via a [2 + 3] cycloaddtion. Aromatic allenyl ketones undergo a phosphine-promoted
New synthesis of a selective estrogen receptor modulator using an enatioselective phosphine-mediated 2+3 cycloaddition
作者:Debra J. Wallace、Robert A. Reamer
DOI:10.1016/j.tetlet.2013.06.023
日期:2013.8
A new synthetic approach to the selective estrogen agonist 1 is described. The key steps in the route are a phosphine catalyzed 2+3cycloaddition between an indanone enone and allenyl methyl ketone, and an unusual Robinson annulation to afford a bicylco[3.2.1]octane. The potential benefits of the new route are discussed along with efforts to render the approach asymmetric.
Selectfluor-promoted α-methylenation of aromatic ketones to terminal olefins using acetonitrile as one carbon source
作者:Zhiqi Liu、Yuan Zhang、Weibin Fan、Deguang Huang
DOI:10.1016/j.tetlet.2022.154179
日期:2022.11
A mehtod for the synthesis of terminalolefins by α-methylenation of aromatic ketones is reported. The reaction was carried out in air using acetonitrile as one carbon source and Selectfluor as a mild oxidant. The scope and versatility of the method were demonstrated with 29 examples. A Selectfluor-promoted oxidative reaction mechanism is proposed based on the experimental results.
palladium-catalyzed carbonylative Heck reaction of aryl thianthrenium salts with carbon monoxide and alkenes has been developed. This protocol can greatly reduce the quantity of olefins used in the carbonylative Heck reaction. In addition, the reaction can also proceed when the coupling partner is a non-activated olefin which is not common in such carbonylative Heck reactions. Combined with C–H thianthrenation