6266-95-1Relevant articles and documents
Single-Flask Multicomponent Synthesis of Highly Substituted α-Pyrones via a Sequential Enolate Arylation and Alkenylation Strategy
Grigalunas, Michael,Wiest, Olaf,Helquist, Paul
supporting information, p. 5724 - 5727 (2016/11/17)
Trisubstituted α-pyrones are obtained by a Pd-catalyzed three-component, single-flask operation via an α-arylation, subsequent α-alkenylation, alkene isomerization, and dienolate lactonization. A variety of coupling components under mild conditions afforded isolated yields of up to 93% of the pyrones with complete control of regioselectivity. Metal dependence was noted for three of the steps of the pathway. Utility of the pyrone products was demonstrated by further transformations providing convenient access to polyaromatic compounds, exhibiting broad molecular diversity.
Palladium-catalyzed α-ketone arylation under mild conditions
Cao, Changsheng,Wang, Lingling,Cai, Zhengyuan,Zhang, Lingqiao,Guo, Jin,Pang, Guangsheng,Shi, Yanhui
supporting information; experimental part, p. 1570 - 1574 (2011/04/17)
The α-arylation of ketones with aryl halides catalyzed by the easily prepared and air-stable palladium complex (SIPr)Pd(Py)Cl2 (3) is described. Complex 3 displays high activity for a variety of aryl halides (activated, unactivated, and sterically hindered aryl halides) under mild conditions. Moreover, both aryl and alkyl ketones can be arylated. The α-arylation of some alkyl ketones can even be run at room temperature. The mono- or diarylated products of the unhindered dialkyl ketone 3-pentanone could be controlled by temperature and the ratio of ketones to aryl halides. Palladium-catalyzed α-ketone arylation of aryl and alkyl ketones with aryl halides is described. A total of 31 examples is presented with yields ranging from 45 to 95%.The mono- or diarylated product of the unhindered dialkyl ketone 3-pentanone could be controlled. Copyright
General and efficient insertions of carbons carrying aryl and heteroaryl groups: Synthesis of α-Aryl- And α-heteroaryl-substituted ketones
Katritzky, Alan R.,Toader, Dorin,Xie, Linghong
, p. 7571 - 7577 (2007/10/03)
Anions formed from the lithiation of a variety of 1-(arylmethyl)- and 1-(heteroarylmethyl)-benzotriazoles 1 with n-BuLi underwent addition to aliphatic and aromatic aldehydes and cyclic and acyclic ketones. Subsequent in situ thermal rearrangements of the intermediates in the presence of zinc bromide provided one-carbon chain-extended or ring-expanded α-aryl- and α-heteroaryl-substituted ketones 2 in moderate to excellent yields in simple one-pot operations with excellent regioselectivity in most cases. Substituent effects on the relative migration rates were investigated in the insertion reactions of 1-(4-methoxybenzyl)benzotriazole (1e) with XC6H4-COPh. The small and negative Hammett ρ+ value (-0.92) suggested that the rearrangements proceed via early, reagent-like, electron deficient transition states.