scholarly journals Monoallylation and benzylation of dicarbonyl compounds with alcohols catalysed by a cationic cobalt(iii) compound

RSC Advances ◽  
2021 ◽  
Vol 11 (16) ◽  
pp. 9235-9245
Author(s):  
Mohan Chandra Sau ◽  
Smita Mandal ◽  
Manish Bhattacharjee
Keyword(s):  
Dicarbonyl Compounds ◽  
Benzylic Alcohols ◽  
Keto Esters

Monoallylation and monoalkylation of diketones and β-keto esters with allylic and benzylic alcohols catalysed by [Cp*Co(CH3CN)3][SbF6]2 (I) are reported.

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.

Direct benzylation of 1,3-dicarbonyl compounds catalyzed by Cs2.5H0.5PW12O40 in solvent-free conditions

2011 ◽  
Vol 89 (12) ◽  
pp. 1533-1538 ◽  
Author(s):  
Ezzat Rafiee ◽  
Maryam Khodayari ◽  
Mohammad Joshaghani
Keyword(s):  
Carbonyl Compounds ◽  
Reaction Times ◽  
Solvent Free ◽  
Dicarbonyl Compounds ◽  
Environmentally Conscious ◽  
Benzylic Alcohols ◽  
Solvent Free Conditions ◽  
Excellent Activity ◽  
High Yields ◽  
Reaction Profile

Various 1,3-dicarbonyl compounds reacted readily with benzylic alcohols in the presence of Cs2.5H0.5PW12O40 salt to produce 2-benzylic-1,3-dicarbonyl compounds in high yields. It was found that this catalyst could be completely recovered and reused without loss of its catalytic activities and is thus environmentally conscious especially in solvent-free conditions. The use of this method provides improved modification of the direct benzylation of 1,3-carbonyl compounds in terms of low reaction times, solvent-free conditions, usage of a small amount of the catalyst, and a clean reaction profile. Furthermore, the use of this catalyst is feasible because of its easy preparation, its easy handling, its stability, its easy recovery, its reusability, being environmentally green, its excellent activity, and its selectivity.

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.

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