Condensation of 2-acylcyclohexane-1,3-diones with aromatic aldehydes

Condensation of 2-propanoyl-, 2-butanoyl-, and 2-pentanoylcyclohexane-1,3-diones with aromatic aldehydes in the presence of secondary amines (diethylamine, pyrrolidine, morpholine, piperidine, and hexamethyleneimine) leads to the formation of the corresponding 2-[1-(dialkylamino)-2-alkyl-3-aryl-2-propylidene]cyclohexane-1,3-diones and derivatives of 4H-chromen-4,5(6H)-dione. A primary screening of some of the resulting enamino derivatives for fungicidal activity has been performed.     

Condensation of quinolin-5-amine with aromatic aldehydes and cyclohexane-1,3-dione

7-Aryl(hetaryl, cyclohexenyl)-7,10,11,12-tetrahydrobenzo[b][1,7]phenanthrolin-8(9H)-ones were synthesized by three-component condensation of aromatic and heteroaromatic aldehydes and cyclohex-3-ene-1-carbaldehyde with quinolin-5-amine and cyclohexane-1,3-diones.     

Three-component condensation of 2-naphthylamine with aromatic aldehydes and 5-(2-furyl)-1,3-cyclohexanedione

Three-component condensation of 5-(2-furyl)-1,3-cyclohexanedione with 2-naphthylamine and aromatic or heteroaromatic aldehydes afforded 12-aryl(hetaryl)-9-(2-furyl)-7,8,9,10,11,12-hexahydrobenzo[a]-acridin-11-ones possessing two asymmetric carbon atoms (C⁹ and C¹²). The products were found to be formed as mixtures of diastereoisomers.     

Synthesis of 2-(Tetrazolylacetyl)cyclohexane-1,3-diones

Russian Journal of General Chemistry - 2-(Tetrazolylacetyl)cyclohexane-1,3-diones were synthesized via C-acylation of cyclohexane-1,3-diones with tetrazolylacetic acids in the presence of...     

Condensation of 2- tosylaminoindole with aromatic aldehydes

The condensation of 2-tosylaminoindole and 1-methyl-2-tosylaminoindoline with aromatic aldehydes gives primarily trans-3-arylidene derivatives, which exist in two tautomeric forms in solution.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 343–347, March, 1976.     

Condensation of 2-Alkylcyclohexane-1,3-diones with Cyclic Azomethines

Reaction of 2-acylcyclohexane-1,3-diones with 5- and 6-membered cyclic azomethines (3,4-dihydro-2H-pyrrole and 2,3,4,5-tetrahydropyridine) furnished derivatives of 2,3,3a;,4,8,9-hexahydropyrrolo[1,2-a]quinoline-5,6(1H,5aH)-dione and 3,4,4a,5,9,10-hexahydro-1H-pyrido[1,2-a]quinoline-6,7(2H,8H)-dione respectively. In reaction with 7-membered 3,4,5,6-tetrahydro-2H-azepine we failed to isolate polycyclic nitrogen-containing products.     

Synthesis of 2-(12-aryldodecanoyl)cyclohexane-1,3-diones

Synthesis was developed of 2-(10-undecenoyl)cyclohexane-1,3-diones containing in the side chain keto and hydroxy groups and a phenyl substituent. The synthesis is underlain by a nitrile oxide approach. The scheme included isoxazole synthesis for the protection of the β,β′-tricarbonyl fragment, building up of a heterocycle by 1,3-dipolar cycloaddition of nitrile oxide in situ to the terminal double bond, cycle opening (of isoxazole and isoxazoline), and alkaline hydrolysis.     

β,β-Dinitrostyrenes in reactions with cyclohexane-1,3-diones

The Michael-type addition of dimedone and dihydroresorcinol to β,β-dinitrostyrenes occurs easily without a catalyst. The adducts cyclize into 3-aryl-2-nitro-2,3,4,5,6-hexahydrobenzofuran-4-ones under the action of triethylamine.     

Condensation of hydroxy naphthazarins with aromatic aldehydes

Hydroxy naphthazarins (2,5,8-trihydroxy-1,4-naphthoquinones) react with aromatic aldehydes containing no hydroxy groups at position 2 under mild acid catalysis to form 3,3′-(arylmethylene)bisnaphthazarins. On the example of o-vanillin, it was shown that the reaction of 2-hydroxybenzaldehydes with hydroxy naphthazarins under the same conditions leads to 7,10-dihydroxy-12H-benzo[b]xanthene-6,11-dione derivatives.     

Condensation of 5-quinolylamine with aromatic aldehydes and dimedone

Condensation of 5-quinolylamine with dimedone and aldehydes of aromatic and heteroaromatic series afforded 10,10-dimethyl-7-aryl(heteryl)-7,10,11,12-tetrahydro-9H-benzo[b]-1,7-phenanthrolin-8-ones.     

Synthesis of heterocyclic compounds from cyclohexane-1,3-diones (review)

The literature data on the synthesis of partially hydrogenated heterocyclic compounds containing a 3-oxocyclohexene structural fragment condensed with five-, six-, or seven-membered oxygen-, nitrogen-, and sulfur-containing heterorings from cyclohexane-1,3-diones and their derivatives are examined in this review.     

On water noncatalytic tandem Knoevenagel–Michael reaction of aldehydes,N,N’-dimethylbarbituric acid and cyclohexane-1,3-diones

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Highly diastereoselective synthesis of tetrahydrobenzofuranones by palladium-catalyzed reaction of propargylic carbonates with 2-substituted cyclohexane-1,3-diones

The reaction of propargylic carbonates with 2-substituted cyclohexane-1,3-diones in the presence of palladium catalyst is described. Substituted tetrahydrobenzofuranones having a quaternary carbon stereocenter were synthesized in a highly diastereoselective manner.     

Acyl furans from cyclohexane-1,3-diones – A synthesis of hibiscone C

A direct route to acyl furans was developed using dithiane anion addition followed by deprotection/aromatization. This led to an efficient synthesis of hibiscone C.     

Synthesis of exo- and endocyclic enamino derivatives of 2-(3-arylprop-2-enoyl)cyclohexane-1,3-diones

Condensation of 2-acetylcyclohexane-1,3-diones with aromatic aldehydes in the presence of piperidine, pyrrolidine, hexamethyleneimine, or morpholine gave the corresponding 2-(3-arylprop-2-enoyl)cyclohexane-1,3-diones as the major products and 2-[3-aryl-1-cycloalkylaminoprop-2-en-1-ylidene]cyclohexane-1,3-diones as minor ones. Endocyclic enamino derivatives were synthesized in two steps through enol methyl ethers which reacted with amines. Endocyclic enamino derivatives of 2-(3-arylprop-2-enoyl)cyclohexane-1,3-diones containing an aryl group on the nitrogen atom readily underwent cyclization to 1,2,3,4,5,6,7,8-octahydroquinoline-4,5-dione derivatives.     

Facile three-component coupling procedure for the synthesis of substituted tetrahydroisoindole-1,3-diones from alpha,beta-unsaturated aldehydes

[reaction: see text]. A new one-pot procedure for the efficient synthesis of a small library of amino-functionalized tetrahydroisoindole-1,3-dione derivatives was developed. This three-component coupling reaction comprises subsequent condensation and Diels-Alder reactions of ubiquitous available starting materials (alpha,beta-unsaturated aldehydes, amide, and maleimide). The synthesized compounds share a substituted tetrahydroisoindole motif in an endo fashion.     

Construction of three stereocenters via hydrogenative desymmetrization of 2,2,5-trisubstituted cyclohexane-1,3-diones

A Ru-catalyzed hydrogenative desymmetrization of 2,2,5-trisubstituted cyclohexane-1,3-diones was developed for construction of three stereocenters including two coherent and discontiguous chiral centers and a chiral quaternary carbon with excellent enantio-and diastereoselectivities.Stereodivergent synthesis of four stereoisomers could be conducted with high enantioselectivities.The desymmetrization could be achieved at gram scale without loss of reactivity and optical purity,and a formal synthesis of bioactive molecule(-)-isocelorbicol was completed.     

One-pot multistep synthesis of 4-acetoxy-2-amino-3-arylbenzofurans from 1-aryl-2-nitroethylenes and cyclohexane-1,3-diones

[reaction: see text] A novel method for synthesizing 4-acetoxy-2-amino-3-arylbenzofurans (4) from 1-aryl-2-nitroethylenes (1) and cyclohexane-1,3-diones (2) is described. The method features one-pot operation of a solution of 1 and 2 in THF with catalytic Et3N (rt, 12 h) followed with Ac2O, Et3N, and DMAP (rt, 5 h), although the process consists of 13 elementary reactions.