Cubane derivatives 7. Synthesis and molecular structure of 4-bromo-1-hydroxymethylcubane

The present study concerned with reduction of methyl 4-bromocubanecarboxylate (1) with lithium aluminum hydride and aluminum hydride in THF. An efficient procedure was developed for the synthesis of 4-bromo-1-hydroxymethylcubane (2) based on reduction of compound 1 with aluminum hydride under mild conditions. The structure of 2 was established by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1461–1464, June, 2005.     

Synthesis of 2-carbethoxybenzofuran derivatives

A mixture of 3-formyl and 3-acetoxymethyl derivatives is formed in the oxidation of 2-carbethoxy-3-methyl-7-ethylbenzofuran with selenium dioxide. Reduction with lithium aluminum hydride gives 2,3-dihydroxymethyl derivatives, which are converted to 2,3-diformyl derivatives by successive oxidation. A number of derivatives of 3-methyl-7-ethylbenzofurancarboxylic acid were obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 756–759, June, 1987.     

Phenothiazine syntheses. XVIII. 2-Aminophenothiazine derivatives

2-(-chloroacetylamido)-2-(-chloropropionylamido)-2-(benzylideneamino)- and 2-(o-hydroxybenzyllideneamino)phenothiazines are synthesized and reduced by lithium aluminum hydride to 2-ethylamino-, 2-propylamino-, 2-benzylamino-, and 2-(o-hydroxybenzylamino)phenothiazine. Reduction of the methyl and ethyl esters of phenothiazinecarbamic-2 acid by lithium aluminum hydride gives 2-methylaminophenothiazine.For Part XVII see [1].     

Studies on the syntheses of heterocyclic compounds. Part DLXXXII . Synthesis of benzo[a] quinolizine derivatives and pyrrolo[2,1-a] isoquinoline derivatives by phenolic cyclization

Phenolic cyclization of 3-hydroxy phenethylamine with acylbutyric acid and acylpropionic acid afforded the lactam of the corresponding benzol[a] quinolizine and pyrrolo[2, 1-a]isoquinoline derivatives, which were reduced with lithium aluminum hydride to give the benzol[a]quinolizine and pyrrolo[2,1 -a] isoquinoline derivatives, respectively. The configurations of acetyl derivatives of these products were determined.     

Synthesis and reduction of derivatives of aziridinemono- and-dicarboxylic acids

Amides and esters of aziridine-2-carboxylic acid were synthesized by the reaction of 1,1,1-trimethyl-2-(2-carboxyethyl)hydrazinium derivatives with an anion-exchange resin or with sodium hydride. Enamines were obtained from 1,1,1-trimethyl-2-[1,2-bis(alkoxycarbonyl)ethyl]hydrazinium salts and basic agents. Methods for the synthesis of amides of aziridine-2,2- and aziridine-2,3-dicarboxylic acids were developed. The stereochemistry of the esters and amides of aziridine-2,3-dicarboxylic acids was established. Dialkylcarbamoylaziridines were reduced with lithium aluminum hydride to 2-(N,N-dialkylaminomethyl)aziridines. The reduction of esters of aziridine-2-carboxylic acid and their functionally substituted derivatives leads to the formation of 2-hydroxymethylaziridines. An O-silylation product was obtained by silylation of 2-hydroxymethylaziridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1227–1235, September, 1983.     

Synthesis,structure, and acylation of dihydroquinopimaric acid hydroxy derivatives

Reduction conditions of methyl dihydroquinopimarate with sodium borohydride and lithium aluminum hydride were established. As a result of the reduction 14β-hydroxy, 17α-hydroxy, 14β,17α-dihydroxy, and 14β,17α,21α-trihydroxy derivatives were obtained. The structure of methyl esters of 14β-acetoxy- and 17α-hydroxydihydroquinopimaric acid was established by XRD and NMR methods. Mono-, di-, and triacylates were obtained from the diterpene alcohols.     

Synthesis of thiazole-containing benzo-crown ethers

A series of benzo-crown ethers containing the thiazole subcyclic moity have been synthesized. Reaction of 1,2-bis(thioamidomethyloxy)benzene 2 with ethyl bromopyruvate in ethanol provided 1,2-bis(thiazolyl)benzene 4 (80%) along with thiazole 5 (14%). Reduction of 4 with lithium aluminum hydride followed by mesylationbromination gave 7 . Similar treatment of 5 with lithium aluminum hydride followed by bromination resulted in 12 . Benzo-crown ethers 8, 9, 10 , and 13 were prepared from the reactions of 4-bromomethylthiazole derivatives 7 and 12 with catechol and resorcinol derivatives in the presence of potassium hydride.     

Synthesis of 2,3-diformyl-5-ethylbenzofuran and its derivatives

A mixture of 3-formyl and 3-acetoxymethyl derivatives is formed in the oxidation of 2-carbethoxy-3-methyl-5-ethylbenzofuran with selenium dioxide. Reduction of the products with lithium aluminum hydride gives the corresponding 2,3-dihydroxymethyl derivatives, which are converted to 2,3-diformyl derivatives by successive oxidation by the Fetizon method and with manganese dioxide. The corresponding benzofuro[2, 3-d]pyridazines were synthesized by reaction of 2-carbethoxy-3-formyl-5-ethylbenzofuran with hydrazine hydrate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 893–895, July, 1982.     

Synthesis of 2-phenyl-3,4-dihydro-2H- and -3,4,5,6-tetrahydro-2H-1,6-benzothiazocine derivatives

The resynthesis of 2-phenyl-3,4-dihydro-2H-benzothiazocin-5(6H)-one (1) was investigated in order to prepare derivatives with potential CNS activity. Lactam 1 could be converted to amidine derivatives 6a-e via the intermediacy of the thioether 5a. Reduction of 1 with lithium aluminum hydride gave amine 8a . Reductive alkylation of 8a gave 9a and 9b while acylation of 8a gave derivatives 10a-d . No interesting biological properties were found for these compounds.     

The reduction of l-methyl-3-methoxy-5-arylpyrrole-2- and -4-carboxylic esters with selected reducing agents

Three new rnethoxypyrrole esters, ethyl 1-methyl-3-methoxy-5-phenylpyrrole-2-earboxylate, diethyl l-methyl-3-methoxy-5-phenylpyrrole-2,4-diearboxylate, and ethyl l-methyl-2-phenyl-4-methoxypyrrole-3-carboxylate were reduced with diborane/tetrahydrofuran, lithium aluminum hydride, and some related reducing agents. In each case diborane reduced the ethoxycarbonyl group to a methyl group and lithium aluminum hydride reduced it to a hydroxymethyl group.     

Synthesis of stereoregular heteropolysaccharides having amino-groups by ring-opening copolymerization of 1,6-anhydro-azido-sugar derivatives

The cationic, ring-opening copolymerization of 1,6-anhydro-2-azido-3,4-di-0-benzyl-2-deoxy-(2-ABG), -3-azido-2,4-di-0-benzyl-3-deoxy- (3-ABG), -4-azido-2,3-di-0-benzyl-4-deoxy-β-D -glucopyranose (4-ABG) with 1,6-anhydro-2,3,4-tri-0-benzyl-β-D -glucopyranose (LGTBE) was investigated with phosphorus pentafluoride as catalyst at low temperatures, giving highly stereoregular, (1→6)-α-linked copolymers with number-average molecular weights of 3.90 × 10⁴?9.27 × 10⁴. Structure and composition of the copolymers were determined by ¹H- and ¹³C-NMR spectroscopies and elemental analysis, which indicated that copolymerization occurred in a stereoregular manner to give azido groups containing (1→6)-α-linked glucopyranan derivatives. The differences in polymerizability among the three azido monomers are discussed. Regioselective reduction of three kinds of heteropolysacharide derivatives which had different quantities of azido groups at C-2, -3, or -4 position with lithium aluminum hydride and subsequent debenzylation of the copolymers with sodium in liquid ammonia produced amino-group-containing heteropolysaccharides.     

Etude en serie as-triazine. X. Réactions nucleophiles sur les triazines-1,2,4 ones-5

The action of Grignard reagents on 6-methylas-triazin-5-one and some methyl derivatives has been studied. The orientation of the reaction is controlled mainly by steric hindrance between the reagent and the substituent at position 6. Comparative studies using lithium aluminum hydride have also been carried out.     

Synthesis and Enantiodifferentiating Properties of Chiral Aza Crown Ethers

Alkylation of 2-substituted (4S,5S)-4,5-bis(hydroxymethyl)-1,3-dioxolanes with 9-benzyl-1,17-diiodo-3,6,12,15-tetraoxa-9-azaheptadecane afforded new chiral aza and diaza crown ethers as a result of [1+1] and [2+2] additions. Their catalytic debenzylation gave the corresponding derivatives with a secondary amino group. The reaction of diethyl (+)-tartrate and diethyl (4S,5S)-1,3-dioxolane-4,5-diacetates with 1,8-diamino-3,6-dioxaoctane led to formation of chiral macrocyclic lactams which were reduced with lithium aluminum hydride. The resulting diaza crown ethers were tested for enantioselectivity in complex formation with L- and D-valine methyl ester by the potentiometric method. In most cases, the aza crown ethers showed better enantioselectivity than their oxygen analogs.     

Synthetic porphyrins. I. Synthesis and spectra of some para-substituted meso - Tetraphenylporphines

A series of derivatives of meso-tetraphenylporphine, with neutral, acidic and basic functional groups, has been prepared. Several of these compounds were synthesized directly via the Rothemund reaction, under a variety of conditions to obtain optimal yields; others were prepared by interconversions of various functional groups. Drastic reaction conditions employed for hydrolysis, alcoholysis, or lithium aluminum hydride reduction did not affect the porphine ring system. The two amino derivatives showed anomalous spectra in the visible range.     

Synthesis of new pyrido[2,3-d]pyrimidine derivatives

The mutual condensation of 4-aminouracil or 2,4-diamino-6-hydroxypyrimidine with bisacetonitrile and aldehydes was used to synthesize 2,4-dioxo-5-R-7-methyl-6-cyano-1,2,3,4,5,8-hexahydropyrido[2,3-d]pyrimidine and 2-amino-4-oxo-5-R-7-methyl-6-cyano-3,4,5,8-tetrahydropyrido[2,3-d]pyrimidine derivatives, which were oxidized with chromic anhydride to the corresponding 2,4-dioxo-5-R-7-inethyl-6-eyano-1,2,3,4-tetrahydropyrido[2,3-d]pyrimidine and 2-amino-4-oxo-5-R-7-methyl-6-cyano-3,4-dihydro[2,3-d]pyrimidines. The IR and UV spectra of the synthesized compounds were recorded.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 422–425, March, 1972.     

Synthesis of 2-ethoxy-2-carbethoxy-δ5 -dihydropyrans and their derivatives

Acrolein and methyl vinyl ketone undergo diene condensation with ethyl -ethoxyacrylate to give the corresponding 2-ethoxy-2-carbethoxy-⁵-dihydropyrans in 50–60% yields. The reduction of the latter with lithium aluminum hydride gave the hydroxymethyl derivatives of dihydropyrans, while ammonolysis gave amides of 2-ethoxy-⁵-dihydropyran-2-carboxylic acids.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 452–453, April, 1972.     

Synthesis and properties of derivatives ofsym-triazine. 16. Synthesis of amine and diamine derivatives ofsym-triazine containing sterically hindered phenol groups from 6-alkyl(aryl)thio-2,4-bis(trichloromethyl)-sym-triazine

The reaction of 6-alkyl(aryl)thio-2,4-bis(trichloromethyl)-sym-triazines with ammonia and primary and secondary amines is studies. It is shown that, depending on the reaction conditions, the replacement of either one or both of the trichloromethyl groups takes place. 6-alkyl(aryl)thio-2,4-diamono-sym-triazines containing sterically hindered phenol groups are synthesized.I. M. Gubkin State Petroleum and Gas Academy, Moscow, 117917. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 224–231., Ferbruary, 1995. Original article submitted December 21, 1994.     

The Stereoselective Synthesis of Indoloquinolizines

Carboline was reduced with lithium aluminum hydride to provide carboline-alcohol whichreacted with methyl vinyl ketone to form the corresponding hydroxymethyl-amino-ketone. Underphase transfer condition it can be converted into enantiomerically pure indoloquinolizines. The cycliza-tion mechanism was also illustrated here.     

A Facile Synthesis of Functionalized 1,2,6,7-Tetrahydroimidazo[1,5-c]pyrimidine-3,5-diones

A Pd-mediated hydrogenation of ethyl 6-azidomethyl-1,2,3,4-tetrahydro-4-R-2-oxo-5-pyrimidinecarboxylates leads to the corresponding ethyl 6-aminomethyl1,2,3,4-tetrahydro-4-R-2-oxo-5-pyrimidinecarboxylates. The latter react with bis(trichloromethyl)carbonate, yielding the title ethyl 1,2,3,5,6,7-hexahydro-7-R-3,5-dioxoimidazo[1,5-c]pyrimidine-8-carboxylates.

Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.     

Synthesis of carbamate derivatives of 2,3-dihydro-4<Emphasis Type="Italic">H</Emphasis>-1,4-benzoxazine

Alkylation of methyl 2-hydroxyphenylcarbamates with 1,2-dibromoethane in acetone in the presence of K₂CO₃ gave the corresponding methyl 6(7)-R-2,3-dihydro-4H-1,4-benzoxazine-4-carboxylate. Alkylation of methyl 2-hydroxyphenylcarbamates with chloromethyloxirane was accompanied by recyclization of the oxirane ring with formation of methyl 6(7)-R-3-hydroxymethyl-2,3-dihydro-4H-1,4-benzoxazine-4-carboxylates.