The Retro-Michael Reaction of 1,5-Dicarbonyl Compounds: Scope and Limitation

1999 ◽  
Vol 64 (1) ◽  
pp. 107-113 ◽  
Author(s):  
Jian-Xin Wang ◽  
Tong-Shuang Li
Keyword(s):  
Good Yield ◽  
Steam Distillation ◽  
Michael Reaction ◽  
Glass Wool ◽  
Dicarbonyl Compounds ◽  
Keto Esters ◽  
Tricyclic Compounds ◽  
Keto Acids

Under catalysis of NaOH or KOH adsorbed on glass wool and by using steam distillation, (20R,S)-4,4,5,14-tetramethyl-18,19-dinor-13,17-seco-5β,8α,9β,10α,14β-cholestane-13,17-dione (1) and 3,14-dioxo-14,15-seco-5α-cholestan-15-al (4) gave good yield (>59%) of the corresponding tricyclic compounds (8a, 8b and 10a) via a retro-Michael reaction at 250 °C. While 5-oxo-4-nor-3,5-secocholestan-3-oic acid (6) and ethyl 5-oxo-4-nor-3,5-secocholestan-3-oate (7) afforded low yield (<15%) of the retro-Michael cleavage products (12a, 12b) at the same conditions. Thus, the retro-Michael reaction worked well for 1,5-diketones and 1,5-keto aldehydes but gave poor yield for 1,5-keto esters and 1,5-keto acids.

Pyridinium ylids in synthesis. II. Acylation and the synthesis of b-dicarbonyl compounds

1967 ◽  
Vol 20 (11) ◽  
pp. 2455 ◽  
Author(s):  
CA Henrick ◽  
E Ritchie ◽  
WC Taylor
Keyword(s):  
Acid Chlorides ◽  
Dicarbonyl Compounds ◽  
Keto Esters

The acylation of N-pyridinium ylids with acid chlorides or anhydrides yields C-acylated ylids which may be reductivaly cleared to yield P-diketones or P-keto esters, depending on the starting materials. The u.v., i.r., and N.M.R. spectra of the ylids are discussed.

Heterogeneous Amine Catalyst Grafted on Amorphous Silica: An Effective Organocatalyst for Microwave-promoted Michael Reaction of 1,3-Dicarbonyl Compounds in Water

2006 ◽  
Vol 35 (8) ◽  
pp. 926-927 ◽  
Author(s):  
Hisahiro Hagiwara ◽  
Sachiyo Inotsume ◽  
Masakazu Fukushima ◽  
Takashi Hoshi ◽  
Toshio Suzuki
Keyword(s):  
Amorphous Silica ◽  
Michael Reaction ◽  
Dicarbonyl Compounds

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.

ChemInform Abstract: UNUSUAL MICHAEL REACTION OF ACYCLIC 1,3-DICARBONYL COMPOUNDS WITH NITROOLEFINS. A NOVEL PYRROLE SYNTHESIS

1982 ◽  
Vol 13 (21) ◽  
Author(s):  
A. GOMEZ-SANCHEZ ◽  
B. M. STIEFEL ◽  
R. FERNANDEZ-FERNANDEZ ◽  
C. PASCUAL ◽  
J. BELLANATO
Keyword(s):  
Michael Reaction ◽  
Dicarbonyl Compounds

2-Azanorbornane-Based Amino Alcohol Organocatalysts for Asymmetric Michael Reaction of β-Keto Esters with Nitroolefins

2019 ◽  
Vol 2019 (24) ◽  
pp. 3882-3889 ◽  
Author(s):  
Rei Togashi ◽  
Madhu Chennapuram ◽  
Chigusa Seki ◽  
Yuko Okuyama ◽  
Eunsang Kwon ◽  
...  
Keyword(s):  
Amino Alcohol ◽  
Michael Reaction ◽  
Keto Esters ◽  
Asymmetric Michael Reaction

scholarly journals Highly Enantioselective Construction of Quaternary Stereocenters onβ-Keto Esters by Phase-Transfer Catalytic Asymmetric Alkylation and Michael Reaction

2003 ◽  
Vol 115 (34) ◽  
pp. 4111-4111 ◽  
Author(s):  
Takashi Ooi ◽  
Takashi Miki ◽  
Mika Taniguchi ◽  
Misato Shiraishi ◽  
Mifune Takeuchi ◽  
...  
Keyword(s):  
Michael Reaction ◽  
Phase Transfer ◽  
Asymmetric Alkylation ◽  
Keto Esters ◽  
Catalytic Asymmetric ◽  
Quaternary Stereocenters
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