@article {2904,
	title = {CRYSTAL-STRUCTURE CORRELATIONS IN THE PHOTOCHEMISTRY OF DIMETHYL 9-PHENYL-9,10-DIHYDRO-9,10-ETHENOANTHRACENE-11,12-DICARBOXYLATE},
	journal = {Acta Crystallographica Section B-Structural Science},
	volume = {49},
	year = {1993},
	note = {ISI Document Delivery No.: LU318Times Cited: 15Cited Reference Count: 12Part 4},
	month = {Aug},
	pages = {754-760},
	type = {Article},
	abstract = {{A study of the photochemistry of the title 9-phenyl-dibenzobarrelene-11,12-diester (1) reveals the formation of a semibullvalene derivative, dimethyl 8b-phenyl-4b,8b,8c,8d-tetrahydrodibenzo[a,f]cyclopropa[cd]pentalene-8c,8 d-dicarboxylate (2), in acetone solution, with an additional cyclooctatetraene (COT) photoproduct, dimethyl 5-phenyldibenzo[a,e]cyclooctene-6,12-dicarboxylate (3), in acetonitrile, benzene and in solid-state photolysis. Crystal data: T = 294 K, Cu Kalpha},
	keywords = {DIBENZOBARRELENE, PHOTOISOMERIZATION, REARRANGEMENT, SOLID-STATE PHOTOCHEMISTRY},
	isbn = {0108-7681},
	url = {<Go to ISI>://A1993LU31800026},
	author = {Pokkuluri, P. R. and Scheffer, J. R. and Trotter, J.}
}
@article {2904,
	title = {CRYSTAL-STRUCTURE CORRELATIONS IN THE PHOTOCHEMISTRY OF DIMETHYL 9-PHENYL-9,10-DIHYDRO-9,10-ETHENOANTHRACENE-11,12-DICARBOXYLATE},
	journal = {Acta Crystallographica Section B-Structural Science},
	volume = {49},
	year = {1993},
	note = {ISI Document Delivery No.: LU318Times Cited: 15Cited Reference Count: 12Part 4},
	month = {Aug},
	pages = {754-760},
	type = {Article},
	abstract = {{A study of the photochemistry of the title 9-phenyl-dibenzobarrelene-11,12-diester (1) reveals the formation of a semibullvalene derivative, dimethyl 8b-phenyl-4b,8b,8c,8d-tetrahydrodibenzo[a,f]cyclopropa[cd]pentalene-8c,8 d-dicarboxylate (2), in acetone solution, with an additional cyclooctatetraene (COT) photoproduct, dimethyl 5-phenyldibenzo[a,e]cyclooctene-6,12-dicarboxylate (3), in acetonitrile, benzene and in solid-state photolysis. Crystal data: T = 294 K, Cu Kalpha},
	keywords = {DIBENZOBARRELENE, PHOTOISOMERIZATION, REARRANGEMENT, SOLID-STATE PHOTOCHEMISTRY},
	isbn = {0108-7681},
	url = {<Go to ISI>://A1993LU31800026},
	author = {Pokkuluri, P. R. and Scheffer, J. R. and Trotter, J.}
}
@article {2909,
	title = {SUBSTITUENT EFFECTS ON THE DI-PI-METHANE PHOTOREARRANGEMENT OF 9,10-ETHENOANTHRACENE DERIVATIVES},
	journal = {Tetrahedron Letters},
	volume = {34},
	number = {1},
	year = {1993},
	note = {ISI Document Delivery No.: KE371Times Cited: 12Cited Reference Count: 20},
	month = {Jan},
	pages = {35-38},
	type = {Article},
	abstract = {The photochemical result of placing electron-donating and electron-withdrawing substituents at the vinyl and aryl positions of the 9,10-ethenoanthracene nucleus is reported. The results are discussed in terms of the radical stabilizing and polar effects of the substituents on the biradical intermediates involved.},
	keywords = {BRIDGEHEAD, BRIDGING REGIOSELECTIVITY, PHOTOISOMERIZATION, REARRANGEMENT},
	isbn = {0040-4039},
	url = {<Go to ISI>://A1993KE37100006},
	author = {Rattray, G. and Yang, J. and Gudmundsdottir, A. D. and Scheffer, J. R.}
}
@article {7244,
	title = {PROTOTROPIC CONTROL OF ORGANIC-PHOTOCHEMISTRY - HYDROGEN-BONDING EFFECTS ON THE DI-PI-METHANE PHOTOREARRANGEMENT},
	journal = {Journal of Organic Chemistry},
	volume = {57},
	number = {1},
	year = {1992},
	note = {ISI Document Delivery No.: GY184Times Cited: 6Cited Reference Count: 54},
	month = {Jan},
	pages = {241-247},
	type = {Article},
	abstract = {The IR and UV spectra as well as the photochemistry of the isopropyl monoester of dibenzobarrelene dicarboxylic acid 2 were analyzed in detail in several media. A correlation was found between the photochemical results and the spectroscopically detected hydrogen-bonded structures of 2. An equilibrium between dimeric (2-HD) and intramolecularly hydrogen bonded (2-HI) structures was detected by IR spectroscopy in nonpolar solvents having weak hydrogen-bond-accepting capabilities. The ratio of the two regioisomeric dibenzosemibullvalene products 3 and 4 formed in the di-pi-methane photorearrangement of 2 was found to correlate with such an equilibrium, and it was concluded that intramolecular (2-HI) and dimeric (2-HD) hydrogen-bonded structures display significantly different photochemical reactivity. The infrared spectra and the photoproduct ratio in polar solvents possessing hydrogen-bond-accepting capabilities (e.g., acetonitrile), on the other hand, turned out to be concentration independent. High regioselectivity was found in the solid state where the dimer 2-HD is the only species, leading to 4 as the major product. In contrast, 3 was obtained preferentially in aqueous sodium bicarbonate solutions where 2 exists as the carboxylate anion. Supporting evidence regarding the different hydrogen bonding arrangements in 2 was found in the solvent effects on its UV spectra.},
	keywords = {ABSORPTION, DIBENZOBARRELENES, EXCITED-STATE, LASER EXCITATION FLUORESCENCE, METHYL SALICYLATE, ORTHO-HYDROXYBENZALDEHYDE, PHOTOISOMERIZATION, REARRANGEMENTS, SOLID-STATE, STATE PROTON-TRANSFER},
	isbn = {0022-3263},
	url = {<Go to ISI>://A1992GY18400043},
	author = {Garciagaribay, M. A. and Scheffer, J. R. and Watson, D. G.}
}
@article {7027,
	title = {ASYMMETRIC INDUCTION IN THE SOLID-STATE PHOTOCHEMISTRY OF AMMONIUM-SALTS},
	journal = {Photochemistry and Photobiology},
	volume = {54},
	number = {4},
	year = {1991},
	note = {ISI Document Delivery No.: GD934Times Cited: 11Cited Reference Count: 9},
	month = {Oct},
	pages = {535-538},
	type = {Article},
	abstract = {A general approach to using crystal chirality in asymmetric synthesis is described. An example consists of the preparation of crystalline salts of dimethyl 9-amino-9,10-ethenoanthracene-11,12-dicarboxylate (1) with optically active sulfonic acids. Photolysis of the salts in the solid state generates a product that has chiral centers in the amine-containing portion of the molecule (di-pi-methane photorearrangement). The optical activity in the photoproduct was determined by polarimetry and NMR chiral shift reagent analysis, which revealed enantiomeric excesses ranging from 30 to 68\% depending on the optically active sulfonic acid employed. In contrast to the results in the crystalline state, irradiation of the salts in acetonitrile gave racemic photoproduct.},
	keywords = {PHOTOISOMERIZATION},
	isbn = {0031-8655},
	url = {<Go to ISI>://A1991GD93400005},
	author = {Gudmundsdottir, A. D. and Scheffer, J. R.}
}
