Sterically controlled recyclable system. Reversible photoredox reactions between anthraquinone and hindered tertiary amines

Journal Article · Wed Sep 08 00:00:00 EDT 1993 · Journal of the American Chemical Society; (United States)

DOI:https://doi.org/10.1021/ja00071a014· OSTI ID:5146606

Gan, H; Whitten, D G ^[1]

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1. Univ. of Rochester, NY (United States)

Photochemical reactions of 9,10-anthraquinone (AQ) with sterically hindered tertiary amines have been studied. The reactivity and products are strongly dependent on the structure of the tertiary amine. Irradiation of AQ in the presence of the sterically hindered amine 1,2,2,6,6-pentamethyl-4-piperidinol (3) (or 1,2,2,6,6-pentamethylpiperidine (5)) in degassed dry benzene leads chiefly to the formation of 9-hydroxy-9-[N-(2,2,6,6-tetramethyl-4-piperidinol)-methyl]anthr one (8), which is found to be metastable at room temperature under vacuum. The reaction may be thermally reversed to regenerate the starting materials. The photolysis products and thermal reversion are solvent dependent. While in dry benzene adduct 8 is the major product, in dry acetonitrile the ionic redox products AQH-and iminium cation are detected and no thermal reversal occurs. The results are explained in terms of equilibrium between a product ion pair (AQH[sup [minus]], iminium[sup +]) and a metastable adduct 8. In the presence of water, the reaction leads to the formation of a stable product, 9-hydroxy-9-(hydroxymethyl)anthrone (6). Different reactivity is observed upon irradiation of AQ in the presence of the sterically less hindered tertiary amine trans-tropine (1). 47 refs., 4 figs., 3 tabs.

• DOE Contract Number: FG02-86ER13504
• OSTI ID: 5146606
• Journal Information: Journal of the American Chemical Society; (United States), Vol. 115:18; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
25 ENERGY STORAGE
AMINES
MOLECULAR STRUCTURE
PHOTOCHEMICAL REACTIONS
REDOX REACTIONS
ANTHRAQUINONES
ADDUCTS
ELECTRON TRANSFER
EQUILIBRIUM
PHOTOCHEMICAL ENERGY STORAGE
PHOTOLYSIS
RADIATION EFFECTS
RECYCLING
SOLVENTS
STEREOCHEMISTRY
AROMATICS
CHEMICAL REACTIONS
DECOMPOSITION
ENERGY STORAGE
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
QUINONES
STORAGE
400201* - Chemical & Physicochemical Properties
400500 - Photochemistry
250800 - Energy Storage- Chemical