Chemical transformations of tetracyclo[3.3.1.1<Superscript>3,7</Superscript>.0<Superscript>1,3</Superscript>]decane (1,3-dehydroadamantane): III. Reactions of 1,3-dehydroadamantane with isothiocyanates

1,3-Dehydroadamantane reacted with phenyl isothiocyanate at 120–130°C under solvent-free conditions to give 4-(adamantan-1-yl)phenyl isothiocyanate. The selectivity of its reactions with benzyl and phenethyl isothiocyanates in which the isothiocyanato group is separated from the benzene ring by methylene or ethylene bridge was lower, and adamantylation of the para position of the benzene ring was accompanied by adamantylation of the methylene groups.     

Chemical Transformations of Tetracyclo[3.3.1.13,7.01,3]decane (1,3-Dehydroadamantane): IX. Noncatalytic Reactions with Alkylarenes

Russian Journal of Organic Chemistry - The reaction of 1,3-dehydroadamantane with alkylbenzenes was studied for the first time. It involved the C–H bond of the alkyl substituent in the...     

Chemical transformations of tetracyclo[3.3.1.1<Superscript>3,7</Superscript>.0<Superscript>1,3</Superscript>]decane (1,3-dehydroadamantane): IV. Reaction of 1,3-dehydroadamantane with dicarboxylic acids esters

Adamantylation of esters of dicarboxylic acids with 1,3-dehydroadamantane under mild conditions afforded in high yields diesters of (adamantan-1-yl)-substituted unsymmetrical dicarboxylic acids.     

Chemical transformations of tetracyclo[3.3.1.1.<Superscript>3,7</Superscript>.0.<Superscript>1,3</Superscript>]decane (1,3-dehydroadamantane): I. Reaction of 1,3-dehydroadamantane with carboxylic acids esters

Adamantylation of carboxylic acids esters was performed with 1,3-dehydroadamantane for the first time. The reaction proceeds under mild conditions and can be used as a convenient single stage procedure for the synthesis of esters of branched carboxylic acids having an adamantyl group in the α-position to the carbonyl group.     

Chemical Transformations of Tetracyclo[3.3.1.1.3,7.0.1,3]decane (1,3-Dehydroadamantane): VIII. Reaction of 1,3-Dehydroadamantane with Aliphatic Aldehydes

Russian Journal of Organic Chemistry - The reaction of 1,3-dehydroadamantane with aliphatic aldehydes involves the Ca-H bond and forms hardly accessible branched 2-(1-adamantyl)alkylaldehydes in...     

Chemical transformations of tetracyclo[3.3.1.1<Superscript>3,7</Superscript>.0<Superscript>1,3</Superscript>]decane (1,3-dehydroadamantane): II. Reaction of 1,3-dehydroadamantane with <Emphasis Type="Italic">N,N</Emphasis>-dialkylcarboxamides

Alkylation of N,N-dialkylcarboxamides with 1,3-dehydroadamantane has been accomplished for the first time. The reaction involves the C–H bond in the α-position with respect to the carbonyl group and provides a convenient one-step preparation of substituted carboxylic acid amides containing an 1-adamantyl substituent and a pharmacophoric group in the amide moiety.     

Hydrogenolysis of 7-phenyltricyclo[4.1.0.0<Superscript>2,7</Superscript>]heptan-1-carboxylic acid. Synthesis of ketones with tricyclo[4.4.0.0<Superscript>2,7</Superscript>]decane and tricyclo[5.4.0.0<Superscript>2,8</Superscript>]undecane skeletons

Hydrogenation of 7-phenyltricyclo[4.1.0.0^2,7]heptane-1-carboxylic acid over Raney nickel occurred in the syn-stereoselective fashion to give anti-7-phenylbicyclo[3.1.1]heptane-exo-6-carboxylic acid. The latter was used to synthesize 4,5-benzotricyclo[4.4.0.0^2,7]dec-4-en-3-one and two isomeric higher homologs, 5,6-benzotricyclo[5.4.0.0^2,8]undec-5-en-3-and-4-ones.     

Synthesis of 1,11,11-trimethyl-3,6-diazotricyclo [6.2.1.0<Superscript>2,7</Superscript>]undeca-2,6-diene and 1,15,15-trimethyl-3,10-diazotetracyclo[10.2.1.0<Superscript>2,11</Superscript>.0<Superscript>4,9</Superscript>]pentadeca-2,4(9),5,7,10-pentaene from camphoroquinone enantiomers

Optically active camphordihydro-2,3-pyrazine and camphorquinoxaline were prepared from camphoroquinone enantiomers. It was shown that (1S,4R)-(+)-camphoroquinone was formed by oxidation of (1S,3R, 4R)-(−)-3-bromocamphor and (1R,4S)-(−)-camphoroquinone from (1R,3S, 4S)-(+)-3-bromocamphor, respectively. Camphor anhydride was a side product (6–10%) of the reaction. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 50–52, January–February, 2007.     

<Superscript>18</Superscript>F- and <Superscript>11</Superscript>C-labelling of quantum dots with n.c.a. [<Superscript>18</Superscript>F]fluoroethyltosylate and [<Superscript>11</Superscript>C]methyliodide: a feasibility study

Quantum dots functionalized on the outer surface with either amino- or carboxyl functions were labelled with [¹⁸F]fluoroethyltosylate and [¹¹C]methyliodide in order to use the positron emitter-labelled fluorescence agents for multimodality imaging techniques, i.e. fluorescence imaging and positron emission tomography. ¹⁸F-Labelling of both compounds was realized with yields up to 5% as determined by size exclusion chromatography, which is twice as much as reported in literature before [1]. ¹¹C-Labelling of amino- and carboxyl-QDs proceeded with good yields (up to 45 and 35%, respectively) under optimized reaction conditions. In general for both QD-types and both labelling agents the labelling yield increased with the amount of QDs used in the reaction as well as with reaction time and reaction temperature.     

Formation of highly caged compounds through Diels-Alder cycloaddition of 3-bromo-7-(bromomethyl)tetracyclo[5.3.1.0<Superscript>2,6</Superscript>.0<Superscript>4,8</Superscript>]undeca-10(12)-ene-9,11-dione with itself and with cyclopentadiene

Diels-Alder reaction of the cage compound 2 with itself, leading to the highly caged compound 3 , as well as with cyclopentadiene, leading to compounds 4 and 5 , is described.     

Mechanism of Reactions of P(III) Amidoesters with Carboxylic Acid Chlorides

Russian Journal of General Chemistry -     

Synthesis of [<Superscript>14</Superscript>C] quincetone

Summary The water-soluble fullerene derivative C₆₀(OH)_x was radiolabeled with ⁶⁷GaCl₃. The labeling yields were determined by radio-PLC. The effects of pH, reaction time, temperature and the amount of C₆₀(OH)_x on the labeling yields were studied. The stability of ⁶⁷Ga-C₆₀(OH)_x was also examined. The results showed that the labeling yields could reach 97% under the best labeling conditions and the radiochemical purity of ⁶⁷Ga-C₆₀(OH)_x solution kept at 37 °C remained at 88% after 212 hours. The biodistribution studies of ⁶⁷Ga-C₆₀(OH)_x in mice showed a high localization of ⁶⁷Ga-C₆₀(OH)_x in the bone marrow, bone, liver and spleen with slow clearance and a negligible accumulation in the blood. These data suggest that the water-soluble C₆₀(OH)_x, having the same properties as microcolloids, may be used as a carrier of drug system for lymphatic targeting.     

Transformations of phosphazane ligands in the coordination sphere of transition metals. Reactions of phosphinotriazene Ph<Subscript>2</Subscript>P-N(Ph)-N=NPh with Ni<Superscript>0</Superscript> and Ni<Superscript>I</Superscript> complexes

3-(Diphenylphosphino)-1,3-diphenyltriazene Ph₂P-NPh-N=NPh was synthesized. The reactions of this compound with bis(cycloocta-1,5-diene)nickel, (cod)₂Ni, and nickel(I) bis(triphenylphosphino)bis(trimethylsilyl)amide, (Ph₃P)₂Ni-N(SiMe₃)₂, afforded the anionic nickel complex [Ph₄P]⁺[Ni(PhNNNPh)₃]⁻ in 15 and 78% yields, respectively. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1585–1589, July, 2005.     

Reaction of sulphate radical anion (SO<Superscript>.</Superscript><Subscript>4</Subscript><Superscript>-</Superscript>) with hydroxy-and methyl-substituted pyrimidines: a pulse radiolysis study

Reactions of sulphate radical anion (SO·₄ ^-) with 4,6-dihydroxy-2-methyl pyrimidine (DHMP), 2,4-dimethyl-6-hydroxy pyrimidine (DMHP), 6-methyl uracil (MU) and 5,6-dimethyl uracil (DMU) have been studied by pulse radiolysis at pH 3 and at pH 10. The transient intermediate spectra were compared with those from the reaction of hydroxyl radical (·OH). It is proposed that SO·₄ ^- produces radical cations of these pyrimidines in the initial stage. These radical cations are short-lived except in the case of DMHP where a relatively longer lived radical cation is proposed to be formed. When there is a hydrogen atom attached to the N(1) or N(3) position, a deprotonation from these sites is highly favored. When there is no hydrogen attached to these sites, deprotonation from a substituted methyl group is favored. At acidic pH, deprotonation from nitrogen is observed for DHMP, MU and DMU. At basic pH, the radical cation reacts with OH^- leading to the formation of OH adducts.     

Preparation of Complexes η<Superscript>4</Superscript>-4-(1,3-Diphenyl-2-propen-1-one)-η<Superscript>3</Superscript>-3-(1,3,5-triorganyl-1,3,5-triazacyclohexane)carbonyltungsten(0) and Their Reactions with Diethyl Phosphite

New tungsten complexes were prepared of a composition η³-[(1,3,5-triorganyl)-1,3,5-triazacyclohexane]-tricarbonyltungsten(0) where a tridentate coordination of the triazinane fragment to the metal center was found. The reaction of tricarbonyltriazinane tungsten complexes with 1,3-diphenyl-2-propen-1-one (chalcone) under thermochemical activation resulted in replacement of two carbon monoxide molecules in the coordination sphere of tungsten by a chalcone molecule linked to the transition metal atom through a system of π-bonds C=C and C=O. The phosphorylation of η⁴-(1,3-diphenyl-2-propen-1-one)-η³-[(1,3,5-triphenyl)-1,3,5-triazacyclohexane]-monocarbonyltungsten(0) with diethyl phosphite occurred at the carbonyl group of the coordinated heterodiene; the phosphonate thus formed underwent intracomplex phosphonate-phosphate rearrangement affording an organometallic phosphate.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 5, 2005, pp. 793–797.Original Russian Text Copyright © 2005 by Kuramshin, Asafyeva, Cherkasov.     

The thermodynamic characteristics of retention of tricyclo[5.2.1.0<Superscript>2,6</Superscript>]decane isomer molecules on different sorbents in gas chromatography

The thermodynamic characteristics of sorption of the isomeric tricyclo[5.2.1.0^2.6]decane (tetrahydrodicyclopentadiene, TDCPD) molecules were for the first time determined experimentally and by molecular statistical methods under the conditions of gas-adsorption chromatography on graphitized thermal carbon black and gas-liquid chromatography on stationary liquid phases of different polarities (Apiezon L and Carbowax 20M). The effects of the chemical nature of sorbents on the retention of the TDCPD isomers are considered. A procedure for calculating the thermodynamic characteristics of adsorption of molecules with a complex structure is suggested within the framework of the atom-atom approximation of the semiempirical molecular statistical theory of adsorption for the example of isostructural norbornane molecules. The procedure involves simultaneous variation of geometric parameters and refinement of the parameters that determine the special features of the electronic structure. This method was used to determine several geometric parameters of the TDCPD molecules for the first time. The results were in close agreement with the quantum-chemical data.     

Electroswitchable binding of [Co(dipy)<Subscript>3</Subscript>]<Superscript>3+</Superscript> and [Fe(dipy)<Subscript>3</Subscript>]<Superscript>2+</Superscript><Emphasis Type="Italic">n</Emphasis>-sulfonato(thia)calix[4]arenas

The methods of cyclic voltammetry, electrolysis, and spectrophotometry were used to study electrochemical properties of (TCAS + Fe³⁺ + dipy), (CCAS + Fe³⁺ + dipy), and (CCAS + Fe³⁺ + [Co(dipy)₃]³⁺) triple systems (where TCAS is n-sulfonatothiacalix[4]arene, CCAS is tetracarboxylate n-sulfonatocalix[4]arene, and dipy = α,α′-dipyridyl) in an aqueous solution. One-electron reduction of Fe(III) in the (TCAS + Fe³⁺ + dipy) system at pH 2.5 results in electroswitching of iron ions from the lower TCAS ring to the upper ([Fe(dipy)₃]²⁺). Reverse electrochemical switching of the system is impossible due to mediator ([Fe(dipy)₃]^2+/3+) oxidation of TCAS. Reverse electroswitching of Fe(III) ions from unbound to bound state as ([Fe(dipy)₃]²⁺) with CCAS has been revealed in the system (CCAS + Fe³⁺ + dipy) (pH 1.7) upon single-electron transfer, whereas reversible electroswitching by the upper rim of CCAS from one complex ion ([Co(dipy)₃]³⁺) to another ([Fe(dipy)₃]²⁺) has been demonstrated in the system ([Co(dipy)₃]³⁺ + CCAS + Fe³⁺ upon double-electron transfer. In all systems, electric switching was accompanied by synchronous color switching.     

Crystal structures of ethyl-4-(5-bromo-2-hydroxyphenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate and ethyl-1-methyl-15-oxo-2-oxa-14,16-diazatetracyclo [11.3.1.0<Superscript>3.12</Superscript>.0<Superscript>6.11</Superscript>]heptadeca-3,5,7,9,11-pentaene-17-carboxylate

The crystal structures of ethyl-4-(5-bromo-2-hydroxyphenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate and ethyl-1-methyl-15-oxo-2-oxa-14,16-diazatetracyclo[11.3.1.0^3.12.0^6.11]heptadeca-3,5,7, 9,11-pentaene-17-carboxylate were determined by XRD, and the conformations of their structures were determined.     

Glycosylation of Bovine Serum Albumin with D-[<Superscript>14</Superscript>C]-Glucose

Certain parameters of the Maillard reaction between bovine serum albumin (BSA) and D-[¹⁴C]-glucose were investigated.__________Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 275–277, May–June, 2005.