Synthesis of Allenyl Ketones by the Palladium-Catalyzed Carbonylation of 2-Alkynyl Carbonates in the Presence of Soft Carbon Nucleophiles

Synlett ◽  
1991 ◽  
Vol 1991 (09) ◽  
pp. 697-698 ◽  
Author(s):  
Tadakatsu Mandai ◽  
Hiroaki Kunitomi ◽  
Kiyoto Higashi ◽  
Mikio Kawada ◽  
Jiro Tsuji
Keyword(s):  
Carbon Nucleophiles ◽  
Palladium Catalyzed ◽  
Soft Carbon

Synthesis of Allenyl Ketones by the Palladium-Catalyzed Carbonylation of 2-Alkynyl Carbonates in the Presence of Soft Carbon Nucleophiles

Synlett ◽  
1991 ◽  
Vol 1991 (10) ◽  
pp. 697-698 ◽  
Author(s):  
Tadakatsu Mandai ◽  
Hiroaki Kunitomi ◽  
Kiyoto Higashi ◽  
Mikio Kawada ◽  
Jiro Tsuji
Keyword(s):  
Carbon Nucleophiles ◽  
Palladium Catalyzed ◽  
Soft Carbon

scholarly journals Palladium-catalyzed alkylation of unactivated olefins

2004 ◽  
Vol 76 (3) ◽  
pp. 671-678 ◽  
Author(s):  
Ross A. Widenhoefer
Keyword(s):  
Good Yield ◽  
Catalytic Amount ◽  
Outer Sphere ◽  
Deuterium Labeling ◽  
Carbon Nucleophiles ◽  
Keto Esters ◽  
Reactive Carbon ◽  
Aryl Ketones ◽  
Palladium Catalyzed ◽  
Hydride Elimination

The reaction of a 3-butenyl β-diketone with a catalytic amount of PdCl2(CH3CN)2 in dioxane at room temperature led to olefin hydroalkylation and formation of the corresponding 2-acylcyclohexanone in good yield as a single regioisomer. Deuterium-labeling experiments for the hydroalkylation of 7-octene-2,4-dione were in accord with a mechanism involving outer-sphere attack of the pendant enol on a palladium-complexed olefin to form a palladium cyclohexyl species, followed by palladium migration via iterative β-hydride elimination/addition and protonolysis from a palladium enolate complex. In comparison to a 3-butenyl β-diketone, reaction of a 4-pentenyl β-diketone with a catalytic amount of PdCl2(CH3CN)2 in the presence of CuCl2 led to oxidative alkylation and formation of the corresponding 2-acyl-3-methyl-2-cyclohexenone in good yield as a single isomer. Unactivated olefins tethered to less reactive carbon nucleophiles such as β-keto esters, α-aryl ketones, and even dialkyl ketones underwent palladium-catalyzed hydroalkylation in the presence of Me3SiCl or HCl to form the corresponding cyclohexanones in moderate-to-good yield with high regioselectivity.

Sign in / Sign up

Export Citation Format

Share Document