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.

Rhenium- and manganese-catalyzed carbon–carbon bond formation using 1,3-dicarbonyl compounds and alkynes

2010 ◽  
Vol 82 (7) ◽  
pp. 1491-1501 ◽  
Author(s):  
Yoichiro Kuninobu ◽  
Atsushi Kawata ◽  
Salprima S. Yudha ◽  
Hisatsugu Takata ◽  
Mitsumi Nishi ◽  
...  
Keyword(s):  
Molecular Sieves ◽  
Catalytic Amount ◽  
Alder Reaction ◽  
Terminal Alkynes ◽  
Dicarbonyl Compounds ◽  
Keto Esters ◽  
Rhenium Complex ◽  
Diels Alder Reaction ◽  
Carbon Carbon Bond ◽  
Catalyzed Reactions

A rhenium complex, [ReBr(CO)3(thf)]2, catalyzed insertion of terminal alkynes into a C–H bond of active methylene sites of 1,3-dicarbonyl compounds. When a catalytic amount of isocyanide or molecular sieves was added to the reaction mixture, the reaction course changed markedly, and insertion of alkynes into a C–C single bond between α- and β-positions of cyclic and acyclic β-keto esters occurred. The formed acyclic δ-keto esters could be converted to 2-pyranones, which were applied to the synthesis of multisubstituted aromatic compounds via the Diels–Alder reaction and successive elimination of carbon dioxide. In the case of the rhenium-catalyzed reactions between terminal alkynes and β-keto esters without substituent at the α-position, tetrasubstituted benzenes were produced regioselectively by two-to-one reaction of the components. The yields of tetrasubstituted benzenes were improved by using a manganese catalyst.

Highly Enantioselective Michael Addition of Cyclic 1,3-Dicarbonyl Compounds to β,γ-Unsaturated α-Keto Esters

2010 ◽  
Vol 352 (10) ◽  
pp. 1648-1652 ◽  
Author(s):  
Xing-Kuan Chen ◽  
Chang-Wu Zheng ◽  
Sheng-Li Zhao ◽  
Zhuo Chai ◽  
Ying-Quan Yang ◽  
...  
Keyword(s):  
Michael Addition ◽  
Dicarbonyl Compounds ◽  
Keto Esters

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.

ChemInform Abstract: Alternative Preparation of α-Keto Esters from Acid Chlorides.

ChemInform ◽  
2010 ◽  
Vol 26 (44) ◽  
pp. no-no
Author(s):  
A. R. KATRITZKY ◽  
Z. WANG ◽  
A. P. WELLS ◽  
P. Y. STEEL
Keyword(s):  
Acid Chlorides ◽  
Keto Esters

The reaction of malononitrile with some β-dicarbonyl compounds

1975 ◽  
Vol 28 (3) ◽  
pp. 581 ◽  
Author(s):  
JW Ducker ◽  
MJ Gunter
Keyword(s):  
Benzene Solution ◽  
Similar Reaction ◽  
Benzene Derivatives ◽  
Dicarbonyl Compounds ◽  
Keto Esters

The reaction of β-keto esters and amides with malononitrile, in the presence of alcohol, has been shown to proceed through cyanocarbon acid and iminopyran intermediates to yield the pyridones (3).With β- diketones, in benzene solution, a similar reaction is accompanied by the formation of δ-lactams(15) and benzene derivatives (16).

Formation of quaternary centres via iron allyl cations. Rapid entry into spirocyclic ring systems

1997 ◽  
Vol 75 (7) ◽  
pp. 965-974 ◽  
Author(s):  
M. Anne Charlton ◽  
James R. Green
Keyword(s):  
Reductive Cyclization ◽  
Cyclization Reactions ◽  
Dicarbonyl Compounds ◽  
Enol Ethers ◽  
Ring Systems ◽  
Silyl Enol Ethers ◽  
Keto Esters ◽  
Condensation Products ◽  
Ketene Acetals ◽  
Silyl Ketene Acetals

Ester-substituted allyltetracarbonyliron cations react with cycloalkylidene-type silyl enol ethers, silyl ketene acetals, and β-keto-esters to give 1,6-dicarbonyl compounds containing a newly formed quaternary centre. Selected condensation products are converted by enolate chemistry into spirocyclic [4.4], [4.5], and [4.6] systems. Acyloin and other reductive cyclization reactions are employed to convert the condensation products into spirocyclic [4.5], [5.5], and [5.6] systems. Keywords: allyliron complexes, umpolung synthesis, 1,6-dicarbonyls, spirocycle synthesis.

Catalytic asymmetric α-amination of β-keto esters and β-keto amides with a chiral N,N′-dioxide–copper(i) complex

2016 ◽  
Vol 3 (7) ◽  
pp. 809-812 ◽  
Author(s):  
Xiao Xiao ◽  
Lili Lin ◽  
Xiangjin Lian ◽  
Xiaohua Liu ◽  
Xiaoming Feng
Keyword(s):  
Reaction Conditions ◽  
Dicarbonyl Compounds ◽  
Keto Esters ◽  
Highly Efficient ◽  
Catalytic Asymmetric

The highly efficient asymmetric α-amination of β-keto esters and β-keto amides was realized by using a chiral N,N′-dioxide/Cu(i) complex. Under mild reaction conditions, a series of chiral α-amino dicarbonyl compounds were obtained in good result.

scholarly journals DMAP-Catalyzed Reaction of Diethyl 1,3-Acetonedicarboxylate with 2-Hydroxybenzylideneindenediones: Facile Synthesis of Fluorenone-Fused Coumarins

Synlett ◽  
2021 ◽  
Author(s):  
Mohanad Shkoor ◽  
Raghad Bayari
Keyword(s):  
Natural Product ◽  
Single Step ◽  
Facile Synthesis ◽  
Dicarbonyl Compounds ◽  
Keto Esters

AbstractThe base-catalyzed reaction of diethyl 1,3-acetonedicarboxylate with 2-hydroxybenzylidene indenediones was studied. The reaction provides a facile and expeditious protocol for the synthesis of natural product inspired fluorenone-fused coumarins in good to very good yields. This process resembles a combination of domino Michael–intramolecular Knoevenagel–aromatization–lactonization reactions in a single step. Although this reaction operates with many bases, the best yields were obtained with DMAP as a catalyst. This protocol could open new potential avenues for the synthesis of fused coumarins by the reaction of substituted β-keto esters with different 2-(2-hydroxybenzylidenes) of 1,3-dicarbonyl compounds.

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