Synthesis and Some Transformations of 2-(3-Amino-1-Phenylpropyl)furan

A preparative method was developed for the synthesis of ethyl furfurylidenecyanoacetate. Its condensation with phenylmagnesium bromide gave ethyl α-cyano-β-(2-furyl)hydrocinnamate, the decarboxylation of which led to β-(2-furyl)hydrocinnamonitrile. Reduction of this nitrile with lithium aluminum hydride gave 2-(3-amino-1-phenylpropyl)furan. Some of its transformations were studied.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 517–521, April, 2005.     

Selective partial reduction of various heteroaromatic compounds with bridgehead nitrogen via Birch reduction protocol

[reaction: see text] For the first time various heteroaromatic compounds with bridgehead nitrogen, including indolizines, bispyrrolopyrimidines, pyrroloquinolines, pyrroloisoquinolines, and bispyrrolopyrazines, were selectively partially reduced under Birch reduction conditions. It was found that the double bond in the fused heterocycles which possesses the highest LUMO density can be selectively reduced under these conditions. Indolizine 6, containing an ester group at C-6, was reductively alkylated to give dihydroindolizines 8 and 9 possessing a quaternary carbon center in good yield. It was found that ambident substrate 12, under Birch reduction conditions, underwent smooth partial reduction to give 4,5-dihydroquinoline 14 as a sole product with no evidence of reduction of the side chain olefin. It was also shown that electron-rich pyrroloisoquinoline 15, which cannot be reduced via catalytic hydrogenation conditions, was efficiently transformed into its dihydrocounterpart 16 by using the Birch reduction protocol. Finally, it was shown that various fused diazines were smoothly and stereoselectively reduced under Birch reduction conditions to give trans-4,5-disubstituted dihydropyrimidines 30 and 32 in virtually quantitative yields.     

Palladium-Catalyzed cross-Benzannulation of Aminoenynes with Diynes. Highly Regioselective Synthesis of Polysubstituted Anilines

Polysubstituted anilines were prepared by the palladium-catalyzed cross-benzannulation of conjugated aminoenynes 1-4 with diynes 8. The reaction proceeded in a highly regioselective manner under mild conditions, and the anilines were obtained as single regioisomers. Our method complements the well-known precedures for the preparation of polysubstituted anilines which are widely used in organic synthesis.     

Nucleophilic reactions of heterylsilanes and heterylgermanes (review)

We generalize data on the reactivity of furyl-, dihydrofuryl-, tetrahydrofuryl-, dihydropyranyl-, and tetrahydropyranylsilanes and -germanes in reactions with nucleophilic reagents. We show that upon reaction of heterosilanes and heterogermanes with O-, N-, C-, and H-nucleophiles, sequential substitution of the heterocycles occurs at the nucleophilic group. We consider the rearrangement of (2-tetrahydrofuryl)- and (2-tetrahydropyranyl) hydrosilanes with ring expansion, and also rearrangement of linear acyloxymethyl- and halomethylhydrosilanes to the corresponding acyloxy- and halosilanes.Dedicated to Professor A. R. Katritsky on the occasion of his 65th birthday.Translated from Khimiya Geterosiklicheskikh Soedinenii, No. 7, pp. 869–878, July, 1993.     

Comparative asymptotic analysis of coupled and uncoupled thermoelasticity

The asymptotic solution of the three-dimensional dynamic of coupled thermoelasticity problem (with the mutual influence of the strain and temperature fields taken into account) for an isotropic rectangular plate is used to perform a comparative analysis of the results obtained according to this theory and the theory of temperature stresses. The parameters whose values affect the applicability of these theories and of the applied theory used to solve quasistatic problems of thermoelasticity are obtained.     

On Orbit Spaces of Distributive Binary $$G$$ -Spaces

Mathematical Notes - The orbit space of a distributive binary $$G$$ -space is studied. A number of its properties in the case of a compact binarily acting group $$G$$ are established.     

Synthesis of 1-(4-butoxyphenyl)-1-cyclohexyl-3-(4-arylpiperazin-1-yl)-2-phenylpropan-1-ols and their dihydrochlorides

Aminomethylation of 1-(4-butoxyphenyl)-2-phenylethanone with paraformaldehyde and substituted piperazines in ethanol medium results in 1-(4-butoxyphenyl)-3-(4-R-piperazin-1-yl)-2-phenylpropan-1-ones. The latter react with cyclohexylmagnesium halide to give 1-(4-butoxyphenyl)-1-cyclohexyl-3-(4-arylpiperazin-1-yl)-2-phenylpropan-1-ols. Reduction of the prepared β-aminoketones with lithium aluminum hydride in absolute diethyl ether leads to the secondary aminopropanols. The prepared compounds could be converted into the corresponding dihydrochlorides.