Rhodium-catalyzed coupling of α-lactams with indole derivatives

We report herein a method that allows for the formation of a C–N bond between the C–3 carbon of α-lactams and the nitrogen atom of indoles. A general procedure for the coupling of indoles and α-lactams in only 25 min with high yield is reported. The scope of the reaction was extended by the development of a method for the in situ generation of less stable phenyl-substituted α-lactams. The developed method provides an atom-economical method for the formation of substituted α-amino amides that are found in a variety of biologically-active compounds.     

Reactions of α-nitrocinnamic acids esters with indole and its derivatives

Reactions of α-nitrocinnamic acids esters with indole and its derivatives lead to the formation of the products of alkylation at the C₃-reaction center of the heterocycle. The hydrogenation of the adduct of 1-methylindole and α-nitro-β-phenylacrylate on the Raney nickel catalyst afforded indolylaminopropanoate, that was used for the synthesis of ethyl 2-acetylamino-3-(1-methylindol-3-yl)-3-phenylpropanoate, a precursor of the methylated in the indole ring phenyl-substituted tryptophan.     

Synthesis of trifluoromethyl derivatives of pyrrole. Reaction of α,β-unsaturated trifluoromethyl ketones with sodium cyanide

An efficient preparative procedure was developed for the synthesis of 5-hydroxy-5-trifluoromethyl-2-pyrrolidones by the reaction of ,-unsaturated trifluoromethyl ketones with sodium cyanide. Dehydration of these reaction products under mild conditions afforded previously unknown 5-trifluoromethyl-3-pyrrolin-2-ones.     

Reaction of nitroalkanes with levoglucosenone and its α-bromo and α-iodo derivatives. Cyclopentaannulation of α-halocyclenones

Michael reactions of levoglucosenone and its α-bromo and α-iodo derivatives with α,ω-dinitroalkanes were studied under conditions of chemical and electrochemical generation of base. Procedures were developed for stereospecific fusion of a cyclopentane ring to α-bromo- and α-iodolevoglucosenones, 2-iodocyclopent-2-en-1-one, and 2-iodocyclohex-2-en-1-one by the action of 2,2-dimethyl-1,3-dinitropropane.     

Reaction of dibenzylphosphine oxide with α,β-unsaturated O-methyloximes

The reaction of dibenzylphosphine oxide with O-methyloximes of some ,-unsaturated ketones results in the phosphorylation at the -carbon atom to form methoxyiminophosphine oxides, whereas the reaction of dibenzylphosphine oxide with O-methyloximes of ,-unsaturated aldehydes affords aminodihydrophosphole oxides.     

Reaction of 3β-chloro-5α,6α-epoxysteroids with trifluoroacetic acid

It has been established that on the interaction of the 5,6-epoxysteroids (1a–c) with trifluoroacetic acid in chloroform the 6-trifluoroacetates of the 5,6-diols (2a–c) are formed in high yield. The alkaline hydrolysis of the trifluoroacetates (2a–c) leads to the corresponding diols (3a–c).Institute of Bioorganic Chemistry, Belarus' National Academy of Sciences, 220141, Belarus', Minsk, ul. Akad. Kuprevicha, 5/2. Translated from Khimiya prirodnykh Soedinenii, No. 2, pp. 201–204, March–April, 1999.     

Reaction of 8-chloro-5,7-dinitroquinoline with β-dicarbonyl compounds

3-(5,7-Dinitroquinolin-8-yl)pentane-2,4-dione, 5-(5,7-dinitroquinolin-8-yl)pyrimidine-2,4,6-trione, and 5-(5,7-dinitroquinolin-8-yl)-2,2-dimethyl-1,3-dioxane-4,6-dione cesium salts have been synthesized by a simple and efficient procedure via C-arylation of the corresponding β-dicarbonyl compounds with 8-chloro-5,7-dinitroquinoline.     

Reaction of α,β-unsaturated trifluoromethyl ketones with cyclic enamines

The reactions of ,-unsaturated trifluoromethyl ketones containing aromatic and heteroaromatic substituents with 1-morpholinocyclopentene, 1-morpholinocyclohexene, and 1-methyl-4-morpholino-1,2,5,6-tetrahydropyridine were studied. The reactions proceeded stereospecifically to give the corresponding bicyclo[3.2.1]octane, bicyclo[3.3.1]nonane, and azabicyclo[3.3.1]nonane derivatives.     

Reaction of α,β-unsaturated trifluoromethyl ketones with ethyl cyanoacetate

β-Aryl-substituted α,β-unsaturated trifluoromethyl ketones react with ethyl cyanoacetate to give the corresponding Michael addition products, ethyl 3-aryl-2-cyano-6,6,6-trifluoro-5-oxohexanoates, which are formed as mixtures of two diastereoisomers. The reaction time and product yield depend on electron-donating properties of the substituent in the initial ketone. The reaction is not accompanied by intramolecular cyclization of the Michael adducts.     

Reaction of unsymmetrical α,β-unsaturated ketones with thiobarbituric acid

Carbocyclization of unsymmetrical 1,5-diarylpenta-1,4-dien-3-ones with thiobarbituric acid afforded previously unknown 7,11-diaryl-3-thioxo-2,4-diazaspiro[5.5]undecane-1,5,9-triones with high regio- and stereoselectivity. The same spiro compounds were also synthesized by three-component condensation of thiobarbituric acid with the corresponding aromatic aldehydes and 4-arylbut-3-en-2-ones.     

Reaction of Trialkyl Phosphites with α,β-Unsaturated Carbonyl Compounds

Abstract

Reaction of trialkyl phosphites 1 with α,β-unsaturated oxo-compounds 2 gives oxaphospholenes 3 or/and two types of Arbuzov products, γ-keto-phosphonates 4 and alkyl-enol-ethers 5.     

Reaction of α-Pinene with Haloacetic Acids

The reactions of -pinene with chloro-, bromo-, and trichloroacetic acids, accompanied by isomerization of -pinene, were studied.     

Synthesis of hydrogenated indazole derivatives starting with α,β-unsaturated ketones and hydrazine derivatives

The reaction of hydrazine derivatives with α,β-unsaturated ketones, such as cyclohexenyl(phenyl)methanone and (E)-2-benzylidenecyclohexanone, were investigated.The reaction between methylhydrazine and e.g., cyclohexenyl(phenyl)methanone was particularly interesting as 3a,4,5,6,7,7a-hexahydro-1-methyl-3-phenyl-1H-indazole was obtained as the major product together with 4,5,6,7-tetrahydro-2-methyl-3-phenyl-2H-indazole as a minor product.     

Reaction ofβ-arylacryloyloxiranes with phenylhydrazine

The reaction of -arylacryloyloxiranes with phenythydrazine under the conditions of acid catalysis leads to 3 arylvinyl-I-phenylpyrazoles and 2-hydroxymethyl-5-aryl-1,4-pentadien-3-one phenythydrazones.Belorussian State Technological University. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3 pp. 324–327, March, 1996. Original article submitted June 26, 1995.     

Synthetic studies of decursivine derivatives: preparation of key indole alkaloids via α-hydroxyalkylation

2-Hydroxyacetyl indole modified at C-3 position was prepared with an eye to developing a total synthesis of decursivine derivatives (decursivine, serotobenine, moschaminindolol, and flavumindole). The indole was prepared through a sequence of oxalyl chloride introduction at C-3 position of indole and acid chloride reduction with tributyltin hydride. In addition, we report a novel synthesis of fully functionalized Uhle's ketone via ortho-selective α-hydroxyalkylation.