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Updated: Jul 19, 2026

Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes
Published on: April 1, 2013
Disorder-to-order transition of 1,4-dimethylnaphthalene: Formation of molecular complex with water and p-xylene on
M A Evans1, A D Louie, D R Hoss
1Chemistry Department, Westmont College, Santa Barbara, California 93108, USA.
Abstract:
Amorphous 1,4-dimethylnaphthalene, DMN, that can be prepared by vacuum deposition on Al2O3 exhibits relatively intense excimer fluorescence. Upon heating the surface, the adlayer undergoes a disorder-to-order transition, signaled by a decrease in excimer and an increase in monomer fluorescence. In a bilayer experiment, water, which has a lower desorption temperature than DMN, is vacuum deposited first, followed by DMN. When the surface is heated, water percolates through the DMN and forms a molecular H2O-DMN surface complex that desorbs simultaneously. The stoichiometric ratio of this complex was determined to be (DMN)(1.4+/-0.3).H2O. When the bilayer was formed with p-xylene, a complex of DMN-p-xylene was observed that had the stoichiometry of (DMN)(7.9+/-1).p-xylene.
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