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8566539 
Journal Article 
Enthalpies of Hydrogenation of Phenylalkynes: Indirect Determination of the Enthalpy of Formation of Diphenylcyclopropenone 
Davis, HE; Allinger, NL; Rogers, DW 
1985 
Yes 
Journal of Organic Chemistry
ISSN: 0022-3263
EISSN: 1520-6904 
50 
19 
3601-3604 
English 
This paper gives the enthalpies of hydrogenation of some phenylalkynes, measured in hexane solution, which lead to their enthalpies of formation. Measured enthalpies of hydrogenation of phenylacetylene, 1-phenyl-1-propyne, 1-phenyl-1-butyne, 1-phenyl-1-hexyne, diphenylacetylene, and diphenylbutadiyne are -66.1 ± 0.4, -62.2 ± 0.5, -62.7 ± 0.2, -62.6 ± 0.3, -59.6 ± 0.6, and -118.5 ±1.0 kcal mol-1respectively. Our experimental result for diphenylacetylene is not in agreement with group additivity calculations and, when combined with a recent value for the decarbonylation of 2,3-diphenylcycloprop-2-en-l-one, leads to a resonance stabilization for that compound of 22 kcal mol-1or about twice the estimate obtained by the group additivity method. © 1985, American Chemical Society. All rights reserved.