Synthesis of heterocyclic compounds on the basis of cyclohexane-1,3-diones (review)

The literature data for the period 1973–1985 on the synthesis, on the basis of cyclohexane-1,3-diones and their derivatives, of heterocyclic compounds that contain a 3-oxocyclohexene structural fragment or are formed as a result of a change in the cyclohexane ring are examined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 723–738, June, 1988.     

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...     

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.     

Synthesis of pyrroles from heterocyclic compounds (review)

Current information on methods of forming a pyrrole ring from heterocyclic compounds is systematized and generalized. Reaction schemes are discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 291–308, March, 1989.     

Formation of meta-arylsulfanyl- and meta-(alkylsulfanyl)phenols from cyclohexane-1,3-diones

Reaction of cyclohexane-1,3-diones with TsCl/Et₃N and treatment of the resulting 3-(tosyloxy)cyclohex-2-en-1-ones with aryl- or alkyl thiols and K₂CO₃ in MeCN gives 3-(arylsulfanyl)cyclohex-2-en-1-ones or 3-(alkylsulfanyl)cyclohex-2-en-1-ones, respectively. These compounds are easily brominated at C-2 by using NBS in MeCN; exposure to DBU in MeCN at room temperature then causes aromatization to afford meta-arylsulfanyl- and meta-(alkylsulfanyl)phenols.     

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.     

Synthesis of heterocyclic compounds using oxaloacetic ester (review)

Published data on the use of oxaloacetic ester in the synthesis of various heterocyclic systems are discussed. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 163–187, February, 2008.     

Synthesis of heterocyclic compounds based on trichloroacetonitrile (review)

The available literature data on the utilization of trichloroacetonitrile in the synthesis of heterocyclic compounds are correlated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1443–1471, November, 1993.     

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.     

Synthesis of thiocarbonyl and heterocyclic compounds from 2-methylene-1,3-dithietanes

2-Methyl-1,3-dithietanes bearing electron withdrawing groups on the methylene carbon atom were synthesized and their reactivities were studied. These compounds readily underwent a ring-opening reaction with a variety of nucleophic reagents such as amines, alcoholate and thiolate anions to yield thioamides, thionoesters and dithioesters, respectively. The products were applied for synthesis of heterocycles such as thiadiazoles, isothiazolones and pyrazoles.     

Condensation of 2-naphthylamine with aromatic aldehydes and substituted cyclohexane-1,3-diones

New 12-aryl(or hetaryl)-9-methyl(or 4-butoxyphenyl)-8,9,10,12-tetrahydro-7H-benzo[a]acridin-11-ones possessing two asymmetric carbon atoms (C⁹ and C¹²) were synthesized by condensation of 5-methyl-or 5-(4-butoxyphenyl)cyclohexane-1,3-dione with 2-naphthylamine and aromatic or heteroaromatic aldehydes. According to the ¹H NMR data, the products were isolated as mixtures of diastereoisomers.     

1,3-Dioxane-4,6-diones in organic synthesis (review)

Material dealing with methods for obtaining 1,3-dioxane-4,6-diones and their derivatives, methods for cleaving the 1,3-dioxane ring, and, within the framework of a synthone approach, trends in their utilization in organic synthesis is correlated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 579–599, May, 1991.     

Asymmetric catalysis involving heterocyclic compounds (review)

The newest advances in the realization of asymmetric reactions with the aid of both heterogeneous and metal-complex catalysts are examined. Heterocyclic compounds are used as prochiral substrates and chiral ligands in the compositions of the catalysts. Chief attention is directed to the relationship between the enantioselectivity and the structures of the heterocyclic compounds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 291–303, March, 1983.     

Thermal and photochemical 1,3-electrocyclic reactions in the chemistry of three-membered heterocyclic compounds (review)

Recent data on thermal and photochemical 1,3-electrocyclic reactions are examined and systematized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1443–1457, November, 1989.     

Synthesis of heterocyclic compounds in the presence of transition metal complexes (review)

The most recent data on reactions involving the formation of heterocycles that take place in the presence of palladium, nickel, cobalt, and iron complexes are examined. The mechanisms of the reactions are discussed in the light of modern concepts of catalysis by metal complexes. The particular significance of metal complex catalysts for the synthesis of heterocycles with unique structures is demonstrated. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 147–163, February, 1980.     

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.