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Updated: Jun 28, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Enthalpimetry of non-aromatic alkenes
1Chemistry Department The Brooklyn Center Long Island University Brooklyn, New York 11201, U.S.A.
Abstract:
A method of increased sensitivity for hydrogen enthalpimetry of olefins in mumole quantities is reported. The method depends on a linear relationship between the amount of alkene present and the heat given off on hydrogenation at slightly more than 2 atm pressure over palladium catalyst on charcoal. Least-squares analysis of the results shows that the measured heat effect is a linear function of amount of alkene taken, with a relative standard deviation of 1-3% for samples ranging in size from 1.4 to 37.5 mumole. Extension of the method to samples in submicromolar quantities was only partially successful; in a series of measurements extending to a minimum amount of 0.64 mumole, the relative standard deviation rose to 9.6%.
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