Steroids as molecular photonic wires. Z → E olefin photoisomerization by intramolecular triplet-triplet energy transfer with and without intervening olefinic gates

Journal of the American Chemical Society

Volumn 121, Issue 15, 1999, Pages 3618-3632

  Timberlake, Larry D ^a   Morrison, Harry ^a  

^a PURDUE UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

3ALPHA ((DIMETHYLPHENYLSILYL)OXY 17 ETHYLIDENE 6 METHYLENE 5ALPHA ANDROSTANE; 3BETA ((DIMETHYLPHENYLSILYL)OXY) 17 ETHYLIDENE 5ALPHA ANDROSTANE; 3BETA ((DIMETHYLPHENYLSILYL)OXY) 17 ETHYLIDENE 5ALPHA ANDROSTENE; 3BETA ((DIMETHYLPHENYLSILYL)OXY) 17 ETHYLIDENE 6 METHYLENE 5ALPHA ANDROSTANE; ALKENE; STEROID; UNCLASSIFIED DRUG;

ARTICLE; ENERGY TRANSFER; ISOMERISM; PHOTOCHEMISTRY; REACTION ANALYSIS; STRUCTURE ACTIVITY RELATION; THERMODYNAMICS;

EID: 0033594324     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja9808595     Document Type: Article

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58. 35
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80. For some examples of the involvement of through-space intramolecular energy transfer involving flexible tethers connecting donor and acceptor groups, see: Haggquist, G. W.; Katayama, H.; Tsuchida, A.; Ito, S.; Yamamoto, M. J. Phys. Chem. 1993, 97, 9270. Wagner, P. J.; El-Taliawi, G. M. J. Am. Chem. Soc. 1992, 114, 8325. Katayama, H.; Ito, S.; Yamamoto, M. J. Phys. Chem. 1992, 96, 10115. Katayama, H.; Maruyama, S.; Ito, S.; Tsujii, Y.; Tsuchida, A.; Yamamoto, M. J. Phys. Chem. 1991, 95, 3480.
81. For some examples of the involvement of through-space intramolecular energy transfer involving flexible tethers connecting donor and acceptor groups, see: Haggquist, G. W.; Katayama, H.; Tsuchida, A.; Ito, S.; Yamamoto, M. J. Phys. Chem. 1993, 97, 9270. Wagner, P. J.; El-Taliawi, G. M. J. Am. Chem. Soc. 1992, 114, 8325. Katayama, H.; Ito, S.; Yamamoto, M. J. Phys. Chem. 1992, 96, 10115. Katayama, H.; Maruyama, S.; Ito, S.; Tsujii, Y.; Tsuchida, A.; Yamamoto, M. J. Phys. Chem. 1991, 95, 3480.
82. For some examples of the involvement of through-space intramolecular energy transfer involving flexible tethers connecting donor and acceptor groups, see: Haggquist, G. W.; Katayama, H.; Tsuchida, A.; Ito, S.; Yamamoto, M. J. Phys. Chem. 1993, 97, 9270. Wagner, P. J.; El-Taliawi, G. M. J. Am. Chem. Soc. 1992, 114, 8325. Katayama, H.; Ito, S.; Yamamoto, M. J. Phys. Chem. 1992, 96, 10115. Katayama, H.; Maruyama, S.; Ito, S.; Tsujii, Y.; Tsuchida, A.; Yamamoto, M. J. Phys. Chem. 1991, 95, 3480.
83. For some examples of the involvement of through-space intramolecular energy transfer involving flexible tethers connecting donor and acceptor groups, see: Haggquist, G. W.; Katayama, H.; Tsuchida, A.; Ito, S.; Yamamoto, M. J. Phys. Chem. 1993, 97, 9270. Wagner, P. J.; El-Taliawi, G. M. J. Am. Chem. Soc. 1992, 114, 8325. Katayama, H.; Ito, S.; Yamamoto, M. J. Phys. Chem. 1992, 96, 10115. Katayama, H.; Maruyama, S.; Ito, S.; Tsujii, Y.; Tsuchida, A.; Yamamoto, M. J. Phys. Chem. 1991, 95, 3480.
84. There is evidence that for conformers having the donor and acceptor within 3-4 Å of each other, energy transfer occurs in 100 ps or less; cf.: Klán, P.; Wagner, P. J. J. Am. Chem. Soc. 1998, 120, 2198.
85. The total emission spectrum of 4 was measured at 77 K in a methylcylohexane glass containing an equimolar amount of 5 added as a competitive olefin quencher. The spectrum was unchanged, evidence that there is no interTTET in the steroidal olefins under these conditions.
86. We have consistently observed phosphorescence emission from the α and β C3-DPSO/C17 and C17-DPSO/C3 olefins.
87. Turro, N. J. Modern Molecular Photochemistry; University Science Books: Mill Valley, CA, 1991; p 320.
88. 54 (53) Wasielewski, M. R. Chem. Rev. 1992, 92, 435.
89. Clayton, A. H. A.; Scholes, G. D.; Ghiggino, K. P.; Paddon-Row, M. N. J. Phys. Chem. 1996, 100, 10912.