1.3- Diphenyl-2-indanone

The experimental observations in the case of 1,3-diphenyl-2-indanones 157 and 158 demonstrate convincingly that the stereochemical integrity of the two radical centers is maintained to high levels when reactions are carried out in the solid state. Crystals... 

N. P, S COMPOUNDS Acetophenone Methyl acetophenone Phthalic Anhydride Methyl benzoate Indanone Dibenzofuran Diethyl phthal ate Di butylphthalate Di i sobutylphthalate Di (2-ethyl hexyl) phthal ate Diphenyl amine... 

Recent work on the thermal indolization of arylhydrazones has introduced new synthetic possibilities for azaindoles. Kelly et al. refluxed cyclohexanone and deoxybenzoin 2-pyridylhydrazones in diethylene glycol to give 5,6,7,8-tetrahydro-a-carboline (42, R = H) and 2,3-diphenyl-7-azaindole in 70 and 56% yields, respectively, compared with 53 and 12% reported earlier. Similarly, y-carboline 29 was obtained in 95 % yield from cyclohexanone 4-pyTidylhydrazone (lit. 48% ). Several 7-azaindole derivatives were prepared in the same manner. The yields ranged from 5 % for azaindolenine (31) to 88% for 3-phenyl-7-azaindole. 3,3-Dimethyl-7-azaindolenine was obtained in 47 % yield from the isobutyralaldehyde hydrazone. The novel cyclic compounds 40 and 41 were obtained from the 2-pyridylhydrazones of cyclopentanone, a-indanone, and a-tetralone in 67, 95, and 77% yields, respectively. Unfortunately, all attempts to cyclize the acetone, pyruvic acid, and ethyl pyruvate hydrazones were unsuccessful. Also, cyclohexanone and methyl ethyl ketone 5-nitro-2-... 

When treated with boron trifluoride in ether, 3-diazo-l,l,l-triphenylacetone cyclizes almost quantitatively to l,l-diphenyl-2-indanone with loss of nitro-gen 786... 

Analogous decarbonylations have been observed for ketones under ultraviolet irradiation at elevated temperatures. From a preparative point of view the behavior of diphenyl-substituted and a,a-divinyl-substituted ketones is interesting, as they are decarbonylated when their benzene solutions are subjected to ultraviolet irradiation.69 This favorable effect of phenyl sub-stitutents on decarbonylation has been noted also for cyclic ketones for example, under suitable conditions l-phenyl-2-indanone eliminates carbon monoxide and yields 90% of 5,6,ll,12-tetrahydro-5,6-diphenyldibenzo[a,e]-cyclooctene as a mixture of cis- and trans-forms,10 whereas 2-indanone itself is hardly decarbonylated at all in benzene solution. That in other cases decarbonylation is usually more profitable in the gas than in the liquid phase is shown by studies of the photolysis of tetramethyl-l,3-cyclobutanedione which in the gas phase gives 2 equivalents of carbon monoxide and a quantitative yield of 2,3-dimethyl-2-butene.71... 

The application of the Forster reaction to the synthesis of a-diazo ketones is particularly important for derivatives of indanone and steroidal ketones with a methylene group in the a-position to the carbonyl function. The reaction allows functionalization of the a-methylene group. Examples include the synthesis of 2-diazo-3,3-diphenyl-indan-l-one (2-42 Cava et al., 1958) and 16-diazo-3)ff-hydro-xy-androst-5-en-17-one (2-43, Muller et al., 1962 Wheeler and Meinwald, 1988). 

Quinkert, G., Palmowski, J., Lorenz, H. R, Wiersdorff, W. W. and Finke, M., Non-Cheletropic Decarbonylation of 1,3-Diphenyl-Substituted 2-Indanone Derivatives, Angew. Chem. Int. Ed. Engl., 10, 198, 1971. 

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