- Chemically initiated electron exchange luminescence of silyloxyaryl-substituted spiroadamantyl dioxetanes: Kinetics and excited state yields
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The kinetics of the fluoride-induced decomposition of the thermally stable silyloxyaryl-substituted spiroadamantyl dioxetanes la,b and the excited state formation of this chemically initiated electron exchange luminescence (CIEEL) have been investigated. Two timing kinetic regimes flash and glow have been identified, which depend on the fluoride concentration, the first at high, the second at low [F-] triggering, whose detailed kinetic analysis affords the rate constants for the deprotected dioxetanes 2a,b cleavage in acetonitrile and sulfoxide and chemiluminescence measurements the CIEEL and phenolate 4 (CIEEL emitter) excitation yields. Chloro-substitution in the spiroadamantyl dioxetane does not affect the deprotection step k2 but leads toa ca five-fold faster cleavage of the deprotected dioxetane 2, while the chemiexcitation yield is the same for both dioxetanes. The energies of the first excited singlet and triplet states of the emitting phenolate 4 were estimated by AM1 configuration interaction calculations with explicit consideration of acetonitrile as solvent (self-consistent reaction field approach). The first excited singlet and triplet state of the CIEEL emitter phenolate 4 possess π,π* character, as suggested by the π-type molecular orbitals and the large singlet-triplet energy gap. The chemiexcitation of both singlet and triplet states of the excited phenolate 4 is feasible during the dioxetanes 1a,b cleavage, but the experimentally determined high singlet excitation yields suggest that preferentially the phenolate 4 singlet state is populated in the fluoride ion-triggered CIEEL process.
- Trofimov, Alexei V.,Mielke, Karsten,Vasil'ev, Rostislav F.,Adam, Waldemar
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- Structure-reactivity relationships: reactions of a 5-substituted aziadamantane in a resorcin[4]arene-based cavitand
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(Figure presented) The complexatlon properties of two novel C5-substituted adamantanediazirines within the resorcin[4]arene-based cavitand 4 were investigated In DMSO-d6, revealing that binding Is up to 1.4 kcal/mol stronger for halogenated adamantanediazirines when compared with the unsubstituted species. The thermal behavior of 5-bromo-2-aziadamantane (3) was investigated by DSC analysis as the first representative of the adamantanediazirine family In the neat solid state, as well as encapsulated within the aromatic cavity of cavitand 4. In the solid phase, the reactions of photolytically or thermolytically generated 5-bromo-2-adamantanylldene (11) can be controlled by complexation within cavitand 4.
- Wagner, Gerald,Knoll, Wolfgang,Bobek, Michael M.,Brecker, Lothar,Van Herwijnen, Hendrikus W. G.,Brinker, Udo H.
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- Trace analysis of Zn(II), Be(II), and Bi(III) by enzyme-catalyzed chemiluminescence
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A novel technique for the trace analysis of metal ions Zn(II), Be(II), and Bi(III) in bulk solutions is discussed. This technique involves the generation of a chemiluminescence signal from alkaline phosphatase catalyzed hydrolysis of a phosphate derivative of 1,2-dioxetane. Zn(II) can be determined by two methods, reactivation of the alkaline phosphatase apoenzyme and inhibition of the native enzyme. Be(II) and Bi(III) can be determined quantitatively by inhibition of the native enzyme. Subppb to ppm level detection of Zn(II), Be(II), and Bi(III) has been achieved. Initial studies with mixed metals are also reported. The technique described is rapid and sensitive and can be readily applied to the microassay of heavy metal ions.
- Tripathy, Sukant
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- Deuterated chemiluminescent 1,2-dioxetanes
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Deuterium-based i.e. isotopic hydrogen chemiluminescent 1,2-dioxetanes derived from the photo-oxidation of new novel alkenes which are synthesized by the coupling reaction of (a) a saturated or unsaturated cyclic, polycylic, normal or branched chain alkyl, cycloalkyl and spiro-fused and (b) substituted aromatic esters or ketones wherein (a) or (b) or both at least have a deuterium atom or a deuterium atom-containing group. These deuterium-based 1,2-dioxetanes may also have electron donating or withdrawing groups at the four-membered peroxide ring. Thus, the added electronic charge and the isotopic hydrogen or isotopic hydrogen-containing group hereof affects the light producing efficiency of 1,2-dioxetanes.
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(2009/05/29)
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- Chemiluminescent 1,2-dioxetanes
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A method of generating light through chemiluminescence involves providing a stable 1,2-dioxetane of the formula: Wherein (a) R1 and R2 are each, individually, a chemical reactive site or when fused together form a chemical reactive site, and R3 and R4 are each, individually, a chemical reactive site or when fused together form a chemical reactive or (b) R1 has at least two hetero atoms with chemical reactive site and R3 and R4 are inactive site and R2 is a chemical reactive site.
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- Chemiluminescent 1,2-dioxetanes
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A method of generating light through chemiluminescence involves providing a stable 1,2-dioxetane of the formula: Wherein (a) R1 and R2 are each, individually, a chemical reactive site or when fused together form a chemical reactive site, and R3 and R4 are each, individually, a chemical reactive site or when fused together form a chemical reactive or (b) R1 has at least two hetero atoms with chemical reactive site and R3 and R4 are inactive site and R2 is a chemical reactive site.
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- Chlorination of Adamantane and Its Derivatives by Carbon Tetrachloride in the Presence of Manganese-, Vanadium-, and Molybdenum-containing Catalysts
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The feasibility of catalytic chlorination of adamantane and its derivatives by carbon tetrachloride in the presence of manganese-, vanadium-, and molybdenum-containing catalysts activated by nitrile ligands or alcohols was established. The optimum molar ratios of catalyst components and reactants and the optimum reaction conditions for selective syntheses of mono-, di-, and trichlorosubstituted adamantane derivatives with high yields were found.
- Khusnutdinov,Shchadneva,Baiguzina,Lavrent'eva,Burangulova,Dzhemilev
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p. 126 - 133
(2007/10/03)
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- Chemiluminescent 1,2-dioxetanes
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The present invention provides novel 1,2-dioxetanes derived from spiro-fused ketones with or without π-electrons in the ring or with carbon-carbon double bond(s) in the spiro-fused ring. Additionally, these new dioxetanes have electron donating or withdrawing groups at the four-membered peroxide ring to render these dioxetanes active at all sites.
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- Reactions of Bridged Halosubstituted Adamantane Derivatives with Nitric Acid
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Reactions of bridged halosubstituted adamantane derivatives with nitric acid result in nitrolysis products. In the presence of acetic anhydride, the reactions proceed at nodal positions to form nitroxy derivatives, while in the case of 2,2-dichloroadamantane, the formation of a 1,4,4-trichloro-substituted derivative is observed. The nitroxylation of 2-fluoroadamantane results in the formation of predominantly products with the Z-configuration.
- Klimochkin,Leonova,Moiseev,Aleksandrov
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p. 340 - 344
(2007/10/03)
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- REACTION OF ADAMANTANONE, DIAMANTANONE, AND THEIR DERIVATIVES WITH THIONYL CHLORIDE
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In reaction of adamantanone, diamantanone, and their chloro or oxo derivatives with thionyl chloride the oxo group is replaced with two chlorine atoms under formation of geminal dichloro derivatives.The presence of a chlorine atom or an oxo group in both ketones reduces the reaction rate.The reaction rate decreases with decreasing distance between the substituent and the carbonyl group.Ketones with chlorine atom in α- or β-axial position do not react with thionyl chloride.The reaction is accelerated by hydrogen chloride whereas in the presence of pyridine no reaction was observed.
- Janku, Josef,Burkhard, Jiri,Vodicka, Ludek
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p. 2028 - 2034
(2007/10/02)
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- Substituent Effects on the Regioselectivity of Intramolecular Carbene C-H Insertion. Cyclizations of 1- and 5-Substituted 2-Adamantylidenes
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Carbenes, 1-methyl-, 1-chloro-, 5-methyl-, and 5-chloro-2-adamantylidene, were generated by pyrolysis of dry tosylhydrazone alkali salts.Each of these carbenes yielded both possible products of the intramolecular C-H insertion, the corresponding 1- and 3-substituted 2,4-didehydroadamantanes or 1- and 7-substituted 2,4-didehydroadamantanes.The product distribution varies considerably depending on the substituent and its position relative to the carbenic center.The results indicate that the regioselectivity of the intramolecular carbene C-H insertion is sensitive to very small changes in geometry and electron distribution in the system.
- Hirsl-Starcevic, Sanja,Majerski, Zdenko
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p. 2520 - 2525
(2007/10/02)
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- ELECTROPHILIC ATTACK OF ELEMENTAL FLUORINE ON ORGANIC HALOGENS. SYNTHESIS OF FLUOROADAMANTANES
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Elemental fluorine acts on bromo- and iodoadamantanes in an electrophilic mode to produce the corresponding fluoroadamantanes.The course of the reaction was investigated in several solvents.It was found that the best yields of the fluoroadamantanes were obtained when Freon (CFCl3) or Freon-chloroform was used.Using methylene chloride as a solvent with iodoadamantanes-but not with the bromo derivatives-resulted in considerable amounts of the corresponding chloro compounds.
- Rozen, Shlomo,Brand, Michael
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p. 733 - 736
(2007/10/02)
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