1-acetonaphthone

Figure 6.10. Rate constants for quenching of sensitizers by cis- and trans-stilbenes (open and filled circles, respectively). Sensitizers are as follows (1) tri-phenylene, (2) thioxanthone, (3) phenanthrene, (4) 2-acetonaphthone, (3) 1-naphthyl phenyl ketone, (6) crysene, (7) fluorenone, (8) 1,2,5,6-dibenzanthracene, (9) benzil, (10) 1,2,3,4-dibenzanthracene, (11) pyrene, (12) 1,2-benzanthracene, (13) benzanthrone, (14) 3-acetyl pyrene, (15) acridine, (16) 9,10-dimethyl-l,2-benzanthracene, (17) anthracene, (18) 3,4-benzpyrene.<57> Reprinted by permission of the American Chemical Society.

The decomposition of methanesulphonyl azide in isopropyl alcohol could be effected by selective irradiation of 2-acetonaphthone instead of benzophenone 21>. Since 2-acetonaphthone triplets are incapable of hydrogen abstraction from isopropyl alcohol 22>, initiation must occur via transfer of excitation energy to the azide. A marked difference was observed from benzophenone sensitization in that the reaction was extremely slow, gave a nitrogen yield of only 68%, and produced a yellow solution 21>. 

The photoreductions of a number of carbonyl compounds with either lowest mr or jiji triplet states in the presence of tributyltinhydride are reported24. The carbonyl compounds include cyclohexanone and acetone which possess nrr lowest-energy triplets, and 2-acetonaphthone, 1-naphthaldehyde and 2-naphthaldehyde which possess lowest-energy mr triplets. In the case of the two njr triplets, a simple mechanism is proposed which involves the abstraction of a hydrogen atom from the tributyltinhydride by the triplet state... 

Fig. 23. (—) spectrum at atmospheric pressure (—) spectrum under 100 atm of oxygen. 1-naphthaldehyde, 0.20 M in n-hexane 2-acetonaphthone, 2.00 M in chloroform 1-acetonaph-thone, 1.00 M in chloroform. Path length 8.5 cm. (From Warwick and Wells, Ref. >)... 

The photocyanation of 1-nitroazulene was accompanied by a dark reaction and was thus less suitable for mechanistic studies than the methoxylation. 2-Acetonaphthone (Et=59 kcal mole i) and 2-naphthophenone ( t=60 kcal mole i) were found to be efficient sensitizers for the disappearance of 1-nitro azrdene in the methoxylation reaction. The measured rate of product formation, however, seemed to be much lower than the rate of starting material disappearance. This effect has been attributed to sensitized decomposition of the product 104)... 

The remaining compounds possess it,it emitting triplets in all media used (Group III). The members of this class are 1,2-diphenylacetone, o-methoxy-acetophenone, xanthone, and 2 -acetonaphthone. This group is characterized by a long-lived phosphorescence in all solvents and by a decrease in the energy of the emitting triplet upon increased solvent polarity. 

Hydroxy-5,6,7,8-tetrahydro-2-acetonaphthone [3].—On mixing 32 1 g of aluminium chloride with 35 0 g (0 184 mole) of 5,6,7,8-tetrahydro-2-napbthyl acetate [10] a vigorous reaction occurred immediately, and hydrogen chloride was evolved rapidly. After the initial reaction had subsided, the mixture was heated for 0 5 hour at 130°. The tan solid obtained on decomposition of the cooled mixture... 

Methyl 3-methoxy-596 7,8-tetrahydro-2-naphthoate—To 300 ml of potassium hypochlorite solution [12] (ca. 0 46 mole of hypochlorite) at 11° was added, with stirring, 2 0 g (0 0098 mole) of 3-methoxy-5,6,7,8-tetrahydro- 2 acetonaphthone in 60 ml of methanol. The mixture was stirred for 5 hours at 11-30°. Filtration separated 0 92 g of yellow... 

Quantum yields for photoreduction of 1-naphthaldehyde, 2-acetonaphthone,370 and p-phenylbenzophenone365,366 in 2-propanol are all 0.1 or lower, as compared with a limiting value of 2 for benzo-phenone. Since the triplets of the first three compounds undoubtedly possess a 77,77 configuration366,370 and a hundredfold longer lifetime... 

Figure 7 Tautomers of Schiff bases derived from /J-diketone (a-c), from l-hydroxy-2-acetonaphthone (d, e) and from...

Bromo-6 -methoxy-2 -acetonaphthone and 2,2-dibromo-6 -methoxy-2 -acetonaphthone)... 

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