Experimental survey of the kinetics of acene Diels–Alder reactions. (26th June 2015)

• Record Type: Journal Article
• Authors: Qualizza, Brittni A.; Ciszek, Jacob W.
• Is Part Of: Journal of physical organic chemistry. Volume 28:Number 10(2015:Oct.)
• Page Start: 629
• Page End: 634
• Publication Date: 2015-06-26
• Subjects: rubrene -- 4‐methyl‐1, 2, 4‐triazoline‐3, 5‐dione -- UV–vis -- stopped flow -- steric hindrance -- rate constants -- stereoisomers; Chemistry, Physical organic -- Periodicals; 547.1
• DOI: 10.1002/poc.3463
• Languages: English
• ISSNs: 0894-3230

Abstract

Abstract : Second‐order rate constants were gathered for solutionDiels–Alder reactions of substituted and unsubstituted acenes, with the intention of ascertaining ideal diene–dienophile combinations. Particular focus was placed on the larger ring systems namely tetracene, pentacene, and rubrene. The rate constants between the acenes ranged roughly six orders of magnitude, from the slowest reacting diene, rubrene, to the fastest diene, pentacene. The utilized dienophiles covered a large range of reactivity from 2, 3‐dichloromaleic anhydride to tetracyanoethylene. To aid in the interpretation of acene reactivity, constants were compared to the extensive body ofDiels–Alder literature with well‐studied dienes such as anthracene and trans ‐1‐methoxy‐1, 3‐butadiene serving as points of reference. Complex reaction kinetics for the addition of MeTAD and rubrene was found: initial fast consumption generated anintermediate, followed by dramatically slower product formation. The kinetic data creates a foundation for the analysis of prior and future reactions between organic semiconductor acene materials with volatized dienophiles, a surfacefunctionalization technique for enhancing theseelectronic materials . Copyright © 2015 John Wiley & Sons, Ltd. Abstract : The rate profiles for pseudo‐first‐order reactions between tetracene and selected dienophiles. The reactivity ranged roughly two orders of magnitude, from the slowest reacting dienophile (2, 3‐dichloromaleic anhydride, light blue) to the fastest dienophile (N–methylmaleimide, orange). Other utilized dienophiles included, in order of reactivity, maleic anhydride (navy), tetrafluoro‐1, 4‐benzoquinone (purple), and p‐benzoquinone (green).