The Experts below are selected from a list of 192 Experts worldwide ranked by ideXlab platform
Waldemar Adam - One of the best experts on this subject based on the ideXlab platform.
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energy transfer enhanced chemiluminescence of Adamantanone n π and ester π π singlet and triplet excited states in the thermolysis of silyloxyaryl substituted spiroadamantyl dioxetanes
Photochemistry and Photobiology, 1995Co-Authors: Alexei V. Trofimov, Karsten Mielke, R F Vasilev, Waldemar AdamAbstract:— The thermal generation of singlet and triplet excited states from silyloxyaryl-substituted spiroadamantyl dioxetanes lab and the adamantylidineadamantane dioxetane (1c) was investigated by direct and enhanced chemiluminescence (CL). 9,10-Diphenylanthracene (DPA) and 9-fluorenone were used as energy acceptors in the singlet-singlet (S-S), naphthalene and europium chelate Eu(TTA)3Phen (TTA = thenoyltrifluoroacetone, Phen = 1,10-phenanthroline) in the triplet-triplet (T-T) and 9,10-di-bromoanthracene (DBA) in triplet-singlet (T-S) energy transfer experiments. The direct chemiluminescence observed in the thermolysis of dioxetanes lab consisted of fluorescence derived from the singlet-excited Adamantanones 2a,b. In the presence of naphthalene, selective T-S energy transfer with DBA (napthalene as quencher) displayed the Adamantanone triplets 2a,b and with Eu(TTA)3Phen (naphthalene as mediator) also the silyloxyaryl ester 3 triplets. From the Stern-Volmer constants (kTNTT0) the triplet lifetimes t0t of these triplet state products were assessed. By using the Hastings-Weber standard, the total triplet excitation yield (φt) was estimated to be ca 20%. The energies of the first excited singlet and triplet states of the Adamantanones 2a,b and the silyloxyaryl ester 3, the products of the thermally induced decomposition of dioxetanes la-c, were determined by semiempirical calculations (AMI-based configuration interaction), which included explicitly solvent effects on the excitation energies in terms of a self-consistent reaction field approach. The calculations revealed that the first excited singlet and triplet states of the Adamantanones 2a,b are expectedly n,π*-type excitations while the silyloxyaryl ester 3 possesses π,π* character. The semiempirical computations suggest that excitation of the Adamantanones 2a,b as well as the silyloxyaryl ester 3 is feasible in the thermolysis of the spiroadamantyl dioxetanes lab, which has been confirmed by the experimental energy transfer studies.
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ENERGY TRANSFER‐ENHANCED CHEMILUMINESCENCE OF Adamantanone (n,π*) AND ESTER (π,π*) SINGLET AND TRIPLET EXCITED STATES IN THE THERMOLYSIS OF SILYLOXYARYL‐SUBSTITUTED SPIROADAMANTYL DIOXETANES†
Photochemistry and Photobiology, 1995Co-Authors: Alexei V. Trofimov, R. F. Vasil'ev, Karsten Mielke, Waldemar AdamAbstract:— The thermal generation of singlet and triplet excited states from silyloxyaryl-substituted spiroadamantyl dioxetanes lab and the adamantylidineadamantane dioxetane (1c) was investigated by direct and enhanced chemiluminescence (CL). 9,10-Diphenylanthracene (DPA) and 9-fluorenone were used as energy acceptors in the singlet-singlet (S-S), naphthalene and europium chelate Eu(TTA)3Phen (TTA = thenoyltrifluoroacetone, Phen = 1,10-phenanthroline) in the triplet-triplet (T-T) and 9,10-di-bromoanthracene (DBA) in triplet-singlet (T-S) energy transfer experiments. The direct chemiluminescence observed in the thermolysis of dioxetanes lab consisted of fluorescence derived from the singlet-excited Adamantanones 2a,b. In the presence of naphthalene, selective T-S energy transfer with DBA (napthalene as quencher) displayed the Adamantanone triplets 2a,b and with Eu(TTA)3Phen (naphthalene as mediator) also the silyloxyaryl ester 3 triplets. From the Stern-Volmer constants (kTNTT0) the triplet lifetimes t0t of these triplet state products were assessed. By using the Hastings-Weber standard, the total triplet excitation yield (φt) was estimated to be ca 20%. The energies of the first excited singlet and triplet states of the Adamantanones 2a,b and the silyloxyaryl ester 3, the products of the thermally induced decomposition of dioxetanes la-c, were determined by semiempirical calculations (AMI-based configuration interaction), which included explicitly solvent effects on the excitation energies in terms of a self-consistent reaction field approach. The calculations revealed that the first excited singlet and triplet states of the Adamantanones 2a,b are expectedly n,π*-type excitations while the silyloxyaryl ester 3 possesses π,π* character. The semiempirical computations suggest that excitation of the Adamantanones 2a,b as well as the silyloxyaryl ester 3 is feasible in the thermolysis of the spiroadamantyl dioxetanes lab, which has been confirmed by the experimental energy transfer studies.
Alexei V. Trofimov - One of the best experts on this subject based on the ideXlab platform.
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energy transfer enhanced chemiluminescence of Adamantanone n π and ester π π singlet and triplet excited states in the thermolysis of silyloxyaryl substituted spiroadamantyl dioxetanes
Photochemistry and Photobiology, 1995Co-Authors: Alexei V. Trofimov, Karsten Mielke, R F Vasilev, Waldemar AdamAbstract:— The thermal generation of singlet and triplet excited states from silyloxyaryl-substituted spiroadamantyl dioxetanes lab and the adamantylidineadamantane dioxetane (1c) was investigated by direct and enhanced chemiluminescence (CL). 9,10-Diphenylanthracene (DPA) and 9-fluorenone were used as energy acceptors in the singlet-singlet (S-S), naphthalene and europium chelate Eu(TTA)3Phen (TTA = thenoyltrifluoroacetone, Phen = 1,10-phenanthroline) in the triplet-triplet (T-T) and 9,10-di-bromoanthracene (DBA) in triplet-singlet (T-S) energy transfer experiments. The direct chemiluminescence observed in the thermolysis of dioxetanes lab consisted of fluorescence derived from the singlet-excited Adamantanones 2a,b. In the presence of naphthalene, selective T-S energy transfer with DBA (napthalene as quencher) displayed the Adamantanone triplets 2a,b and with Eu(TTA)3Phen (naphthalene as mediator) also the silyloxyaryl ester 3 triplets. From the Stern-Volmer constants (kTNTT0) the triplet lifetimes t0t of these triplet state products were assessed. By using the Hastings-Weber standard, the total triplet excitation yield (φt) was estimated to be ca 20%. The energies of the first excited singlet and triplet states of the Adamantanones 2a,b and the silyloxyaryl ester 3, the products of the thermally induced decomposition of dioxetanes la-c, were determined by semiempirical calculations (AMI-based configuration interaction), which included explicitly solvent effects on the excitation energies in terms of a self-consistent reaction field approach. The calculations revealed that the first excited singlet and triplet states of the Adamantanones 2a,b are expectedly n,π*-type excitations while the silyloxyaryl ester 3 possesses π,π* character. The semiempirical computations suggest that excitation of the Adamantanones 2a,b as well as the silyloxyaryl ester 3 is feasible in the thermolysis of the spiroadamantyl dioxetanes lab, which has been confirmed by the experimental energy transfer studies.
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ENERGY TRANSFER‐ENHANCED CHEMILUMINESCENCE OF Adamantanone (n,π*) AND ESTER (π,π*) SINGLET AND TRIPLET EXCITED STATES IN THE THERMOLYSIS OF SILYLOXYARYL‐SUBSTITUTED SPIROADAMANTYL DIOXETANES†
Photochemistry and Photobiology, 1995Co-Authors: Alexei V. Trofimov, R. F. Vasil'ev, Karsten Mielke, Waldemar AdamAbstract:— The thermal generation of singlet and triplet excited states from silyloxyaryl-substituted spiroadamantyl dioxetanes lab and the adamantylidineadamantane dioxetane (1c) was investigated by direct and enhanced chemiluminescence (CL). 9,10-Diphenylanthracene (DPA) and 9-fluorenone were used as energy acceptors in the singlet-singlet (S-S), naphthalene and europium chelate Eu(TTA)3Phen (TTA = thenoyltrifluoroacetone, Phen = 1,10-phenanthroline) in the triplet-triplet (T-T) and 9,10-di-bromoanthracene (DBA) in triplet-singlet (T-S) energy transfer experiments. The direct chemiluminescence observed in the thermolysis of dioxetanes lab consisted of fluorescence derived from the singlet-excited Adamantanones 2a,b. In the presence of naphthalene, selective T-S energy transfer with DBA (napthalene as quencher) displayed the Adamantanone triplets 2a,b and with Eu(TTA)3Phen (naphthalene as mediator) also the silyloxyaryl ester 3 triplets. From the Stern-Volmer constants (kTNTT0) the triplet lifetimes t0t of these triplet state products were assessed. By using the Hastings-Weber standard, the total triplet excitation yield (φt) was estimated to be ca 20%. The energies of the first excited singlet and triplet states of the Adamantanones 2a,b and the silyloxyaryl ester 3, the products of the thermally induced decomposition of dioxetanes la-c, were determined by semiempirical calculations (AMI-based configuration interaction), which included explicitly solvent effects on the excitation energies in terms of a self-consistent reaction field approach. The calculations revealed that the first excited singlet and triplet states of the Adamantanones 2a,b are expectedly n,π*-type excitations while the silyloxyaryl ester 3 possesses π,π* character. The semiempirical computations suggest that excitation of the Adamantanones 2a,b as well as the silyloxyaryl ester 3 is feasible in the thermolysis of the spiroadamantyl dioxetanes lab, which has been confirmed by the experimental energy transfer studies.
Karsten Mielke - One of the best experts on this subject based on the ideXlab platform.
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energy transfer enhanced chemiluminescence of Adamantanone n π and ester π π singlet and triplet excited states in the thermolysis of silyloxyaryl substituted spiroadamantyl dioxetanes
Photochemistry and Photobiology, 1995Co-Authors: Alexei V. Trofimov, Karsten Mielke, R F Vasilev, Waldemar AdamAbstract:— The thermal generation of singlet and triplet excited states from silyloxyaryl-substituted spiroadamantyl dioxetanes lab and the adamantylidineadamantane dioxetane (1c) was investigated by direct and enhanced chemiluminescence (CL). 9,10-Diphenylanthracene (DPA) and 9-fluorenone were used as energy acceptors in the singlet-singlet (S-S), naphthalene and europium chelate Eu(TTA)3Phen (TTA = thenoyltrifluoroacetone, Phen = 1,10-phenanthroline) in the triplet-triplet (T-T) and 9,10-di-bromoanthracene (DBA) in triplet-singlet (T-S) energy transfer experiments. The direct chemiluminescence observed in the thermolysis of dioxetanes lab consisted of fluorescence derived from the singlet-excited Adamantanones 2a,b. In the presence of naphthalene, selective T-S energy transfer with DBA (napthalene as quencher) displayed the Adamantanone triplets 2a,b and with Eu(TTA)3Phen (naphthalene as mediator) also the silyloxyaryl ester 3 triplets. From the Stern-Volmer constants (kTNTT0) the triplet lifetimes t0t of these triplet state products were assessed. By using the Hastings-Weber standard, the total triplet excitation yield (φt) was estimated to be ca 20%. The energies of the first excited singlet and triplet states of the Adamantanones 2a,b and the silyloxyaryl ester 3, the products of the thermally induced decomposition of dioxetanes la-c, were determined by semiempirical calculations (AMI-based configuration interaction), which included explicitly solvent effects on the excitation energies in terms of a self-consistent reaction field approach. The calculations revealed that the first excited singlet and triplet states of the Adamantanones 2a,b are expectedly n,π*-type excitations while the silyloxyaryl ester 3 possesses π,π* character. The semiempirical computations suggest that excitation of the Adamantanones 2a,b as well as the silyloxyaryl ester 3 is feasible in the thermolysis of the spiroadamantyl dioxetanes lab, which has been confirmed by the experimental energy transfer studies.
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ENERGY TRANSFER‐ENHANCED CHEMILUMINESCENCE OF Adamantanone (n,π*) AND ESTER (π,π*) SINGLET AND TRIPLET EXCITED STATES IN THE THERMOLYSIS OF SILYLOXYARYL‐SUBSTITUTED SPIROADAMANTYL DIOXETANES†
Photochemistry and Photobiology, 1995Co-Authors: Alexei V. Trofimov, R. F. Vasil'ev, Karsten Mielke, Waldemar AdamAbstract:— The thermal generation of singlet and triplet excited states from silyloxyaryl-substituted spiroadamantyl dioxetanes lab and the adamantylidineadamantane dioxetane (1c) was investigated by direct and enhanced chemiluminescence (CL). 9,10-Diphenylanthracene (DPA) and 9-fluorenone were used as energy acceptors in the singlet-singlet (S-S), naphthalene and europium chelate Eu(TTA)3Phen (TTA = thenoyltrifluoroacetone, Phen = 1,10-phenanthroline) in the triplet-triplet (T-T) and 9,10-di-bromoanthracene (DBA) in triplet-singlet (T-S) energy transfer experiments. The direct chemiluminescence observed in the thermolysis of dioxetanes lab consisted of fluorescence derived from the singlet-excited Adamantanones 2a,b. In the presence of naphthalene, selective T-S energy transfer with DBA (napthalene as quencher) displayed the Adamantanone triplets 2a,b and with Eu(TTA)3Phen (naphthalene as mediator) also the silyloxyaryl ester 3 triplets. From the Stern-Volmer constants (kTNTT0) the triplet lifetimes t0t of these triplet state products were assessed. By using the Hastings-Weber standard, the total triplet excitation yield (φt) was estimated to be ca 20%. The energies of the first excited singlet and triplet states of the Adamantanones 2a,b and the silyloxyaryl ester 3, the products of the thermally induced decomposition of dioxetanes la-c, were determined by semiempirical calculations (AMI-based configuration interaction), which included explicitly solvent effects on the excitation energies in terms of a self-consistent reaction field approach. The calculations revealed that the first excited singlet and triplet states of the Adamantanones 2a,b are expectedly n,π*-type excitations while the silyloxyaryl ester 3 possesses π,π* character. The semiempirical computations suggest that excitation of the Adamantanones 2a,b as well as the silyloxyaryl ester 3 is feasible in the thermolysis of the spiroadamantyl dioxetanes lab, which has been confirmed by the experimental energy transfer studies.
Robin G. Pritchard - One of the best experts on this subject based on the ideXlab platform.
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Reversible C–C bond formation: solid state structure of the aldol-like addition product of Adamantanone to a 1,5-diazapentadienyllithium, and its solution state retro-aldol dissociation
Chemical communications (Cambridge England), 2003Co-Authors: Lee Jon Ball, Anthony P. Dickie, Francis S. Mair, David A. Middleton, Robin G. PritchardAbstract:Analysis of crystals of the lithium complex of the tripodal ligand formed upon addition of Adamantanone to a 1,5 diazapentadienyllithium complex reveals a long C–C bond which ruptures upon dissolution in non-co-ordinating solvents.
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reversible c c bond formation solid state structure of the aldol like addition product of Adamantanone to a 1 5 diazapentadienyllithium and its solution state retro aldol dissociation
Chemical Communications, 2003Co-Authors: Lee Jon Ball, Anthony P. Dickie, Francis S. Mair, David A. Middleton, Robin G. PritchardAbstract:Analysis of crystals of the lithium complex of the tripodal ligand formed upon addition of Adamantanone to a 1,5 diazapentadienyllithium complex reveals a long C–C bond which ruptures upon dissolution in non-co-ordinating solvents.
Lee Jon Ball - One of the best experts on this subject based on the ideXlab platform.
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Reversible C–C bond formation: solid state structure of the aldol-like addition product of Adamantanone to a 1,5-diazapentadienyllithium, and its solution state retro-aldol dissociation
Chemical communications (Cambridge England), 2003Co-Authors: Lee Jon Ball, Anthony P. Dickie, Francis S. Mair, David A. Middleton, Robin G. PritchardAbstract:Analysis of crystals of the lithium complex of the tripodal ligand formed upon addition of Adamantanone to a 1,5 diazapentadienyllithium complex reveals a long C–C bond which ruptures upon dissolution in non-co-ordinating solvents.
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reversible c c bond formation solid state structure of the aldol like addition product of Adamantanone to a 1 5 diazapentadienyllithium and its solution state retro aldol dissociation
Chemical Communications, 2003Co-Authors: Lee Jon Ball, Anthony P. Dickie, Francis S. Mair, David A. Middleton, Robin G. PritchardAbstract:Analysis of crystals of the lithium complex of the tripodal ligand formed upon addition of Adamantanone to a 1,5 diazapentadienyllithium complex reveals a long C–C bond which ruptures upon dissolution in non-co-ordinating solvents.
