Stereoselectivity of halomethoxylation of 1-phenyltricyclo-[4.1.0.0<Superscript>2,7</Superscript>]heptane and methyl 7-phenyltricyclo[4.1.0.0<Superscript>2,7</Superscript>]-heptane-1-carboxylate

The stereoselectivity of halomethoxylation of 1-phenyltricyclo[4.1.0.0^2,7]heptane and methyl 7-phenyltricyclo[4.1.0.0^2,7]heptane-1-carboxylate at the central bicyclobutane C¹-C⁷ bond by the action of N-chloro-, N-bromo-, and N-iodosuccinimides in methanol depends on the halogen nature. Conjugate chlorination and bromination are characterized by pronounced anti-stereoselectivity; the contribution of syn-addition slightly increases in going from the monosubstituted tricycloheptane substrate to disubstituted. Iodomethoxylation of the latter is clearly syn-stereoselective.     

Synthesis of 7-sulfonyl-substituted norpinan-6-ones and -thiones from 1-bromotricyclo[4.1.0.0<Superscript>2,7</Superscript>]heptane

1-Bromotricyclo[4.1.0.0^2,7]heptane reacted with benzene- and methanesulfonyl thiocyanates in benzene at 20°C via anti addition to the central C¹–C⁷ bicyclobutane bond with formation of 6-endo-bromo-6-exo-thiocyanato-7-syn-(R-sulfonyl)bicyclo[3.1.1]heptanes. Treatment of the benzenesulfonyl thiocyanate adduct with potassium tert-butoxide in THF at 20°C gave 7-endo-(benzenesulfonyl)norpinan-6-one, whereas the reaction with 1,8-diazabicyclo[5.4.0]undec-7-ene in methylene chloride afforded 7-exo-(benzenesulfonyl)-norpinane-6-thione which was converted into 7-exo-(benzenesulfonyl)norpinan-6-one by alkaline hydrolysis.     

Electrophilic heterocyclization of 6-alken(yn)ylsulfanyl-pyrazolo[3,4-<Emphasis Type="Italic">d</Emphasis>]pyrimidin-4(5<Emphasis Type="Italic">H</Emphasis>)-ones

6-Allylsulfanyl-1-arylpyrazolo[3,4-d]pyrimidin-4(5H)-ones react with iodine and sulfuric acid to give angular pyrazolothiazolopyrimidine derivatives. The reaction of 6-(prop-2-yn-1-ylsulfanyl)-1-(4-tolyl)-pyrazolo[3,4-d]pyrimidin-4(5H)-one with sulfuric acid gives angularly fused pyrazolo[4,3-e][1,3]thiazolo-[3,2-a]pyrimidin-4-one, whereas in the reaction with sodium methoxide linearly fused pyrazolo[3,4-d][1,3]-thiazolo[3,2-a]pyrimidin-4-one was formed. Linearly fused pyrazolo[3′,4′:4,5]pyrimido[2,1-b][1,3]thiazole derivatives were also obtained by reaction of 1-aryl-6-(3-phenylprop-2-en-1-ylsulfanyl)pyrazolo[3,4-d]pyrimidin-4(5H)-ones with sulfuric acid.     

Reactivity of 5-<Emphasis Type="Italic">endo</Emphasis>-hydroxy-4-azatricyclo[5.2.1.0<Superscript>2,6</Superscript>]dec-8-en-3-ones and their isomerization initiated by acids and bases

Study of isomerization of 5-endo-hydroxy-4-azatricyclo[5.2.1.0^2,6]dec-8-en-3-ones under the action of Lewis acids (MgBr₂, AlCl₃), CF₃COOH, and NaH showed that the optimum catalyst of the process was trifluoroacetic acid. In reaction of 4-benzyl-5-endo-hydroxy-4-azatricyclo-[5.2.1.0^2,6]dec-8-en-3-one with anhydrous AlCl₃ in benzene was unexpectedly isolated N-benzyl-3-(diphenylmethyl)bicyclo[2.2.1]hept-5-ene-2-carboxamide. A convenient method was developed for the preparation of 5-exo-alkoxy-4-alkyl(aryl)-4-azatricyclo[5.2.1.0^2,6]dec- 8-en-3-ones.     

Synthesis of N-aryl- and <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-diethyl-9-methyl-11-sulfanylidene-8-oxa-10,12-diazatricyclo[7.3.1.0<Superscript>2,7</Superscript>]trideca-2,4,6-triene-13-carboxamides

Three-component condensation of N-aryl- and N,N-diethyl-3-oxobutanamides with salicylaldehyde and thiourea in ethanol in the presence of sodium hydrogen sulfate afforded N-aryl- and N,N-diethyl-9-methyl-11-sulfanylidene-8-oxa-10,12-diazatricyclo[7.3.1.0^2,7]trideca-2,4,6-triene-13-carboxamides. Reaction of the same compounds in the absence of a catalyst under solvent-free conditions gave N-aryl-6-(2-hydroxyphenyl)-4-methyl-2-sulfanylidene-1,2,3,6-tetrahydropyrimidine-5-carboxamides.     

Halocyclization of 3-{[2-methyl(bromo)prop-2-en-1-yl]-sulfanyl}-5<Emphasis Type="Italic">H</Emphasis>-[1,2,4]triazino[5,6-<Emphasis Type="Italic">b</Emphasis>]indoles

Reactions of 3-[(2-bromoprop-2-en-1-yl)sulfanyl]-5H-[1,2,4]triazino[5,6-b]indole with bromine and of 3-[(2-methylprop-2-en-1-yl)sulfanyl]-5H-[1,2,4]triazino[5,6-b]indole with iodine and bromine afforded 3-halomethyl-10H-[1,3]thiazolo[3′,2′: 2,3][1,2,4]triazino[5,6-b]indol-4-ium halides whose structures were determined by ¹H NMR and X-ray analysis.     

Synthesis,crystal structures,and antibacterial activities of Schiff base zinc(II) complexes [Zn(L<Superscript>1</Superscript>)<Subscript>2</Subscript>] and [Zn(L<Superscript>2</Superscript>)<Subscript>2</Subscript>]

The reaction of cyclopentylamine with 2-hydroxy-1-naphthaldehyde and 5-nitrosalicylaldehyde, respectively, in methanol affords two new Schiff bases, 1-(cyclopentyliminomethyl)naphthalen-2-ol (HL¹) and 4-nitro-2-(cyclopentyliminomethyl)phenol (HL²). Two new zinc(II) complexes, [Zn(L¹)₂] (I) and [Zn(L²)₂] (II), derived from the Schiff bases, have been prepared and characterized by single-crystal X-ray diffraction, FT-IR, and elemental analysis. Complex I crystallizes in the monoclinic space group P2₁/c with a = 17.834(4), b = 14.738(3), c = 9.868(2) Å, β = 91.20(3)°, V = 2593.1(9) ų, Z = 4. Complex II crystallizes in the triclinic space group P \(\bar 1\) with a = 10.206(1), b = 10.502(1), c = 12.554(1) Å, α = 66.771(2)°, β = 78.133(2)°, γ = 76.292(2)°, V = 1191.8(1) ų, Z = 2. The Zn atom in each complex is coordinated by two N and two O atoms from two Schiff base ligands, forming a tetrahedral geometry. The Schiff bases and the complexes were assayed for antibacterial activities.     

Synthesis of fullerene C<Subscript>60</Subscript> monoadducts. Cyclopropanation of C<Subscript>60</Subscript> with sulfonium ylides

3′H-Cyclopropa[1,9](C₆₀-I_h)[5,6]fullerene-3′-carboxylic acid can be synthesized in a good yield by cyclopropanation of fullerene C₆₀ with 2-(dimethyl-λ⁴-sulfanylidene)acetates provided that the ester residue is readily hydrolyzable in acid medium.     

Reaction of 3-oxo-3-R<Superscript>1</Superscript>-<Emphasis Type="Italic">N</Emphasis>-R<Superscript>2</Superscript>-propanethioamides with 2-amino-5-R-pyridines

Direction of a reaction between 3-oxo-3-R¹-N-R²-propanethioamides and 2-amino-5-R-pyridines in acetic acid depends on the structure of initial thioamides: at R¹ = Me, R² = Ar, Et 2-methyl-7-R-4H-pyrido[1,2-a]-pyrimidine-4-thiones are obtained, and at R¹ = Ar, R² = Me form 1-methyl-5-(N-methylaminothiocarbonyl)-4,6-diaryl-1,2-dihydropyridine-2-thiones.     

Reaction of transsilylation of <Emphasis Type="Italic">N</Emphasis>-methyl-<Emphasis Type="Italic">N</Emphasis>-trimethylsilylacetamide with silanes ClCH<Subscript>2</Subscript>SiR<Superscript>1</Superscript>R<Superscript>2</Superscript>Cl

The reaction of N-methyl-N-trimethylsilylacetamide with silanes ClCH₂SiR¹R²Cl (R¹, R² = H, Me; H, Ph; Ph₂) leads to the formation of (O→Si) chelate compounds with pentacoordinate silicon: N-[chloro(methyl)-silyl]methyl-, N-[chloro(phenyl)silyl]methyl-, and N-[chloro(diphenyl)silyl]methyl-N-methylacetamides. From the data of multinuclear NMR spectroscopy, the intermediates of the reaction of N-methyl-N-trimethylsilylacetamide with ClCH₂SiPhHCl and ClCH₂SiPh²Cl are stable in CDCl₃ solution at room temperature during several days and slowly rearrange to the final (O–Si) chelate compounds.     

Fused pyrimidine systems: XVI. Electrophilic intramolecular cyclization of 2-(alkenylsulfanyl)pteridin-4(3<Emphasis Type="Italic">H</Emphasis>)-ones

2-[Allyl(but-3-en-1-yl, pent-4-en-1-yl)sulfanyl]pteridin-4(3Н)-ones at heating in polyphosphoric acid undergo an intramolecular cyclization affording respectively 9-methyl-8,9-dihydro-5H-[1,3]thiazolo[3,2-a] pteridin-5-one and 10-methyl(ethyl)-9,10-dihydro-5Н,8Н-[1,3]thiazino[3,2-a]pteridin-5-ones of angular structure. The cyclization of 2-(alkenylsulfanyl)pteridin-4(3Н)-ones under the action of iodine or arylsulfenyl chlorides afforded iodo(arylsulfanyl) derivatives of angularly fuzed thiazolo- and thiazinopteridines.     

Synthesis and crystal structure of a supramolecular adduct of the aqua nitrato complex of gadolinium [Gd(NO<Subscript>3</Subscript>)(H<Subscript>2</Subscript>O)<Subscript>7</Subscript>]<Superscript>2+</Superscript> with macrocyclic cavitand cucurbit[6]uril

A supramolecular adduct of gadolinium aqua nitrato complex and cucurbit[6]uril { [Gd(NO₃)(H₂O)₇](C₅H₅N)@(C₃₆H₃₆N₂₄O₁₂)}(NO₃)₂·10H₂O is obtained by slow diffusion of methanol into an aqueous solution containing gadolinium nitrate, pyridine, and cucurbit[6]uril. According to single crystal X-ray diffraction data, water molecules coordinated to metal atom make hydrogen bonds to polarized carbonyl groups of the macrocycle. The heptaaquanitratogadolinium(III) [Gd(NO₃)(H₂O)₇]²⁺ cation is structurally characterized for the first time. Crystal system is triclinic, space group \(P\overline 1 \), a = 12.3137(4) Å, b = 14.2334(5) Å, c = 19.5629(6) Å; α = 80.850(1)°, β = 86.879(1)°, γ = 68.855(1)°; V = 3157.15(18) ų, Z = 2. Oriented hydrogen-bonded chains of alternating cucurbit[6]uril molecules and gadolinium aqua cations form in the crystal structure.     

Stereoselective synthesis of (<Emphasis Type="Italic">Z</Emphasis>,<Emphasis Type="Italic">E</Emphasis>)-bis(2-chloroethenyl)tellanes

A procedure for the stereoselective synthesis of dichloro[(Z)-2-chloro-2-phenylethenyl][(4E)-5- chlorooct-4-en-4-yl]-λ⁴-tellane and [(Z)-2-chloro-2-phenylethenyl][(4E)-5-chlorooct-4-en-4-yl]tellane has been developed on the basis of anti-addition of tellurium tetrachloride–phenylacetylene monoadduct to oct-4-yne.     

Formation of mononuclear rhodium(III) sulfates: <Superscript>103</Superscript>Rh and <Superscript>17</Superscript>O NMR study

It was shown that the monomeric rhodium sulfate complexes [Rh(H₂O)₄(SO₄)]⁺, trans-[Rh(H₂O)₂(SO₄)₂]^?, cis-[Rh(H₂O)₂(SO₄)₂]^?, and [Rh(SO₄)₃]^3? were not predominant forms in aqueous solutions. The ¹⁰³Rh NMR chemical shifts of the complexes were assigned, and the conditions for their formation in solutions, concentration parameters, and acidity at which the fraction of the monomers was maximal were determined. The constants of formation of the complexes and ion pair (IP) were estimated: K _IP = 8 ± 3.5, K ₁ ≈ 8, K _2trans ≈ 1, K _2cis ≈ 1, and K ₃ ≈ 2.     

Reactions of 1,3-Dialkyl-5-amino-1,3-dihydro-2<Emphasis Type="Italic">H</Emphasis>-imidazo-[4,5-<Emphasis Type="Italic">b</Emphasis>]pyridin-2-ones with acetylacetone and ethyl acetoacetate

1,3-Dialkyl-5-amino-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-ones reacted with acetylacetone to give the corresponding 4-(1,3-dialkyl-2-oxo-1,3-dihydro-2H-imidazo[4,5-b]pyridin-5-ylamino)pent-3-en-2-ones which underwent intramolecular cyclization to 1,3-dialkyl-5,7-dimethyl-1,3-dihydro-2H-imidazo[4,5-b]-[1,8]naphthyridin-2-ones on heating in polyphosphoric acid or diphenyl ether. Analogous reaction of 1,3-dialkyl-5-amino-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-ones with ethyl acetoacetate led to the formation of ethyl 3-(1,3-dialkyl-2-oxo-1,3-dihydro-2H-imidazo[4,5-b]pyridin-5-ylamino)but-2-enoates whose cyclization afforded 1,3-dialkyl-8-hydroxy-7-methyl-1,3-dihydro-2H-imidazo[5,4-b][1,8]naphthyridin-2-ones.     

Five-membered 2,3-dioxo heterocycles: LVI. Reaction of 3-aroyl-1<Emphasis Type="Italic">H</Emphasis>-pyrrolo[2,1-<Emphasis Type="Italic">c</Emphasis>][1,4]benzoxazine-1,2,4-triones with acyclic enamino ketones

3-Aroyl-1H-pyrrolo[2,1-c][1,4]benzoxazine-1,2,4-triones react with 4-arylaminopent-3-en-2-ones and 3-amino-1,3-diphenylprop-2-en-1-ones to give substituted 4-aroyl-3-hydroxy-1-(o-hydroxyphenyl)-1,7-diazaspiro[4.4]nona-3,8-diene-2,6-diones.     

Synthesis of 1-(1,3-dialkyl-2-oxo-2,3-dihydro-1<Emphasis Type="Italic">H</Emphasis>-imidazo-[4,5-<Emphasis Type="Italic">b</Emphasis>]pyridin-5-yl)-5-oxopyrrolidine-3-carboxylic acids

Nitration of 2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-one gave its 5-nitro derivative which was subjected to alkylation with dimethyl sulfate, diethyl sulfate, and benzyl(dimethyl)phenylammonium chloride. The resulting 1,3-dimethyl-, 1,3-diethyl-, and 1,3-dibenzyl-5-nitro-2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-ones were reduced to the corresponding 1,3-dialkyl-5-amino-2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-ones, and the latter reacted with itaconic acid to produce 1-(1,3-dialkyl-2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-5-yl)-5-oxopyrrolidine-3-carboxylic acids. 1-(2-Oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-5-yl)-5-oxopyrrolidine-3-carboxylic acid was obtained by analogous reaction with 5-amino-2,3-dihydro-1H-imidazo[4,5-b]-pyridin-2-one.     

Crystal and molecular structures and luminescence properties of [Eu(Cin)<Subscript>3</Subscript>]<Subscript><Emphasis Type="Italic">n</Emphasis></Subscript> complex

The crystal structure of europium cinnamate of the composition [Eu(Cin)₃] _n (Cin is cinnamic acid anion C₉H₇O ₂ ^? ) was determined by X-ray crystallography (a = 22.626(1) Å, c = 7.7330(7) Å, space group R3/c, Z = 3, ρ_calc = 1.448 g/cm³). The coordination polyhedron of Eu atoms is a distorted trigonal prism with three centered square faces. The structure is built of infinite polymeric chains [Eu(Cin)₃] _n running along the c axis and linked by van der Waals and π stacking interactions. Luminescent characteristics of the compound were determined.     

Synthesis of New Heterocyclic Systems on the Basis of 7-Benzyl-3-chloro-1-(morpholin-4-yl)-5,6,7,8-tetrahydro-2,7-naphthiridine-4-carbonitrile

Methods have been developed for the synthesis of new 8-amino-3-benzyl-5-(morpholin-4-yl)-1,2,3,4-tetrahydropyrimido[4′,5′: 4,5]thieno[2,3-c][2,7]naphthyridine starting from 7-benzyl-3-chloro-1-(morpholin-4-yl)-5,6,7,8-tetrahydro-2,7-naphthyridine-4-carbonitrile. 8-Hydrazinyl-3-benzyl-5-(morpholin-4-yl)-1,2,3,4-tetrahydropyrimido[4′,5′: 4,5]thieno[2,3-c][2,7]naphthyridine has been converted to isomeric pentacyclic structures with a triazole ring fused through the [c] side of the pyrimidine ring, and their Dimroth rearrangement has been accomplished in both acidic and basic media. New heterocyclic systems containing pyrrolo[1,2-a]pyrimidinone and pyrimido[1,2-a]azepinone fragments were obtained on the basis of the thieno-[2,3-c][2,7]naphthyridine derivative.     

Reactions of 2-(2-propynylsulfanyl)-5,6,7,8-tetrahydrobenzo[<Emphasis Type="Italic">b</Emphasis>]thieno[2,3-<Emphasis Type="Italic">d</Emphasis>]pyrimidin-4(<Emphasis Type="Italic">3H</Emphasis>)-one with arylsulfenyl chlorides

2-(2-propynylsulfanyl)-5,6,7,8-tetrahydrobenzo[b]thieno[2,3-d]pyrimidin-4(3H)-one with arylsulfenyl chlorides in chloroform gave products of anti-Markownikoff Ad _E-addition. The use of nitromethane as solvent in the presence of lithium perchlorate additives favored intramolecular electrophilic cyclization into 1-arylsulfanyl-1,2,6,7,8,9-hexahydro-4H-benzo[4,5]thieno[3,2-e][1,3]thiazolo[3,2-a]-pyrimidin-5-one.