@article {727,
	title = {The photochemistry of trans-1,4,4,4-tetraphenylbut-2-en-1-one: A highly efficient aryl migration (type B) enone photorearrangement},
	journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie},
	volume = {81},
	number = {6},
	year = {2003},
	note = {ISI Document Delivery No.: 706UATimes Cited: 0Cited Reference Count: 18},
	month = {Jun},
	pages = {705-708},
	type = {Article},
	abstract = {Photolysis of trans-1,4,4,4-tetraphenylbut-2-en-1-one (3) in acetonitrile or benzene leads to trans-cis isomerization (7) along with rearrangement to trans-1 -benzoyl-2,2,3-triphenylcyclopropane(8). Formation of the latter product represents a new example of the aryl migration (type B) enone photorearrangement reaction first reported by Zimmerman and co-workers for 4,4-diphenylcyclohex-2-en-1-one (1). The quantum yield in the case of enone 3 (0.4) is approximately 10 times greater than that for 4,4,-diphenylcyclohex-2-en-1-one, a result that is ascribed to steric acceleration of phenyl migration from the triphenylmethyl group plus greater resonance stabilization of the intermediate biradical.},
	keywords = {aryl migration, ASYMMETRIC INDUCTION, di-pi-methane, enone, EXPLORATORY ORGANIC PHOTOCHEMISTRY, MECHANISM, MIGRATION, PHENYL, PHOTOCHEMISTRY, PHOTOCYCLIZATION, REARRANGEMENT, STATE},
	isbn = {0008-4042},
	url = {<Go to ISI>://000184472400035},
	author = {Scheffer, J. R. and Vishnumurthy, K.}
}
@article {4638,
	title = {Porphyrins incorporating heterocyclic N-oxides: (oxidopyridyl)porphyrins, porphyrin-N-oxides, and a tirapazamine-porphyrin conjugate},
	journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie},
	volume = {77},
	number = {2},
	year = {1999},
	note = {ISI Document Delivery No.: 188AZTimes Cited: 9Cited Reference Count: 41},
	month = {Feb},
	pages = {182-198},
	type = {Article},
	abstract = {{Porphyrins containing one to four 3-pyridyl groups as meso-substituents were synthesized via a mixed aldehyde condensation, and then "N-oxidized" with m-chloroperbenzoic acid to produce five novel (oxidopyridyl) porphyrins and seven porphyrin-N-oxides which were characterized by analysis and spectroscopic methods, especially NMR; an X-ray crystal structure of 5-(1-oxido-4-pyridyl)-10, 15,20-triphenylporphyrin was also obtained. Crystals of (oxidopyridyl)triphenylporphyrin are tetragonal},
	keywords = {(oxidopyridyl)porphyrins, ANTICANCER, BIOREDUCTIVE DRUGS, DESIGN, DRUGS, FUNCTIONAL-GROUPS, NICKEL(II), PHENYL, PHOTODYNAMIC THERAPY, porphyrin-N-oxides, tirapazamine},
	isbn = {0008-4042},
	url = {<Go to ISI>://000079823200003},
	author = {Posakony, J. J. and Pratt, R. C. and Rettig, S. J. and James, Brian R. and Skov, K. A.}
}
@article {4327,
	title = {An investigation of the yang photocyclization reaction in the solid state: Asymmetric induction studies and crystal structure-reactivity relationships},
	journal = {Journal of the American Chemical Society},
	volume = {120},
	number = {49},
	year = {1998},
	note = {ISI Document Delivery No.: 149MWTimes Cited: 101Cited Reference Count: 61},
	month = {Dec},
	pages = {12755-12769},
	type = {Article},
	abstract = {The Norrish/Yang type II photochemistry of 16 ketones having the basic cis-4-tert-butyl-1-benzoylcyclohexane or 2-benzoyladamantane structure has been investigated in the solid state and solution. In both media, ketones bearing methyl substituents alpha to the benzoyl group undergo stereoselective Yang photocyclization to afford endo-arylcyclobutanols. Quantum yield and quenching studies in solution show that the reactions are efficient triplet-mediated processes. Asymmetric induction studies were carried out by providing the reactants with carboxylic acid substituents to which "ionic chiral auxiliaries" were attached through salt formation with optically active amines. Irradiation of the salts (17 in total) in solution gave racemic cyclobutanols, but in the crystalline state, moderate to near-quantitative enantiomeric excesses were obtained. Single crystal X-ray diffraction studies were successfully performed on 10 neutral ketones and four salts. This allowed the reactive gamma-hydrogen atoms to be identified and the distance and angular parameters associated with their abstraction to be tabulated. For the 14 compounds whose crystal structures were determined, the average value of d, the C=O ... H abstraction distance, was 2.61 +/- 0.07 Angstrom, and the values of omega (the gamma-hydrogen out-of-plane angle), Delta (the C=O ... H, angle) and a (the C-H-gamma... O angle) were 53 +/- 11, 84 +/- 7, and 115 +/- 2 degrees, respectively. In a similar manner, the geometric parameters associated with the ring closure reactions of the intermediate 1,4-hydroxy biradicals were estimated from the crystallographic data. This indicates that the biradicals are 66.5 +/- 9.8 and 32.7 +/- 3.2 degrees out of alignment for cleavage, but that they are well oriented for cyclization, with radical separations (D) of 3.08 +/- 0.09 Angstrom. For one of the salts in the adamantane series, the solid-state photoreaction was shown to be topotactic; that is, a single crystal of the reactant salt was transformed quantitatively into a single crystal of the corresponding cyclobutanol salt. Since the absolute configuration of the ionic chiral auxiliary in this case was known, this permitted the absolute steric course of the reaction to be mapped by X-ray crystallography and the abstracted gamma-hydrogen to be identified unequivocally. In addition, the crystal structure of a partially reacted crystal containing 60\% product and 40\% reactant was successfully determined. This showed that the two compounds in the mixed crystal have nearly identical shapes and orientations, thus accounting for the single crystal nature of the process. Finally, it was found that ketones lacking methyl substituents alpha to the benzoyl group an either photochemically unreactive or undergo Norrish type II cleavage. Possible reasons for this difference in behavior are presented and discussed.},
	keywords = {BIRADICALS, CHEMISTRY, CONFORMATIONAL MEMORY, HYDROGEN-ATOM TRANSFERS, II PHOTOPROCESSES, KETONES, ORGANIC-PHOTOCHEMISTRY, PHENYL, POLYMERIZATION, SINGLE-CRYSTAL, TRANSITION STRUCTURES, TRIPLET},
	isbn = {0002-7863},
	url = {<Go to ISI>://000077610100007},
	author = {Leibovitch, M. and Olovsson, G. and Scheffer, J. R. and Trotter, J.}
}
@article {4327,
	title = {An investigation of the yang photocyclization reaction in the solid state: Asymmetric induction studies and crystal structure-reactivity relationships},
	journal = {Journal of the American Chemical Society},
	volume = {120},
	number = {49},
	year = {1998},
	note = {ISI Document Delivery No.: 149MWTimes Cited: 101Cited Reference Count: 61},
	month = {Dec},
	pages = {12755-12769},
	type = {Article},
	abstract = {The Norrish/Yang type II photochemistry of 16 ketones having the basic cis-4-tert-butyl-1-benzoylcyclohexane or 2-benzoyladamantane structure has been investigated in the solid state and solution. In both media, ketones bearing methyl substituents alpha to the benzoyl group undergo stereoselective Yang photocyclization to afford endo-arylcyclobutanols. Quantum yield and quenching studies in solution show that the reactions are efficient triplet-mediated processes. Asymmetric induction studies were carried out by providing the reactants with carboxylic acid substituents to which "ionic chiral auxiliaries" were attached through salt formation with optically active amines. Irradiation of the salts (17 in total) in solution gave racemic cyclobutanols, but in the crystalline state, moderate to near-quantitative enantiomeric excesses were obtained. Single crystal X-ray diffraction studies were successfully performed on 10 neutral ketones and four salts. This allowed the reactive gamma-hydrogen atoms to be identified and the distance and angular parameters associated with their abstraction to be tabulated. For the 14 compounds whose crystal structures were determined, the average value of d, the C=O ... H abstraction distance, was 2.61 +/- 0.07 Angstrom, and the values of omega (the gamma-hydrogen out-of-plane angle), Delta (the C=O ... H, angle) and a (the C-H-gamma... O angle) were 53 +/- 11, 84 +/- 7, and 115 +/- 2 degrees, respectively. In a similar manner, the geometric parameters associated with the ring closure reactions of the intermediate 1,4-hydroxy biradicals were estimated from the crystallographic data. This indicates that the biradicals are 66.5 +/- 9.8 and 32.7 +/- 3.2 degrees out of alignment for cleavage, but that they are well oriented for cyclization, with radical separations (D) of 3.08 +/- 0.09 Angstrom. For one of the salts in the adamantane series, the solid-state photoreaction was shown to be topotactic; that is, a single crystal of the reactant salt was transformed quantitatively into a single crystal of the corresponding cyclobutanol salt. Since the absolute configuration of the ionic chiral auxiliary in this case was known, this permitted the absolute steric course of the reaction to be mapped by X-ray crystallography and the abstracted gamma-hydrogen to be identified unequivocally. In addition, the crystal structure of a partially reacted crystal containing 60\% product and 40\% reactant was successfully determined. This showed that the two compounds in the mixed crystal have nearly identical shapes and orientations, thus accounting for the single crystal nature of the process. Finally, it was found that ketones lacking methyl substituents alpha to the benzoyl group an either photochemically unreactive or undergo Norrish type II cleavage. Possible reasons for this difference in behavior are presented and discussed.},
	keywords = {BIRADICALS, CHEMISTRY, CONFORMATIONAL MEMORY, HYDROGEN-ATOM TRANSFERS, II PHOTOPROCESSES, KETONES, ORGANIC-PHOTOCHEMISTRY, PHENYL, POLYMERIZATION, SINGLE-CRYSTAL, TRANSITION STRUCTURES, TRIPLET},
	isbn = {0002-7863},
	url = {<Go to ISI>://000077610100007},
	author = {Leibovitch, M. and Olovsson, G. and Scheffer, J. R. and Trotter, J.}
}
@article {3290,
	title = {THE REACTION OF PHSR(R=FC OR PH) WITH RU-3(CO)(12)},
	journal = {Polyhedron},
	volume = {14},
	number = {19},
	year = {1995},
	note = {ISI Document Delivery No.: RU147Times Cited: 6Cited Reference Count: 28},
	month = {Sep},
	pages = {2653-2661},
	type = {Article},
	abstract = {{The reaction of SPh(2) with Ru-3(CO)(12) affords (mu-SR)(mu-eta(1); eta(6)-C6H5)Ru-3(CO)(8) (Ru-Ru)},
	keywords = {BONDS, CLEAVAGE, CLUSTERS, COMPLEXES, NUCLEARITY, PHENYL, SULFIDES, TRICARBONYL},
	isbn = {0277-5387},
	url = {<Go to ISI>://A1995RU14700008},
	author = {Cullen, W. R. and Rettig, S. J. and Zheng, T. C.}
}
