A new silole‐containing low bandgap polymer is synthesized by replacing the 5‐position carbon of PCPDTBT with a silicon atom (PSBTBT). Through experiments and computational calculations, we show that the material properties, particular the packing of polymer chains, can be altered significantly. As a result, the polymer changes from amorphous to highly crystalline with the replacement of the silicon atom.
The reaction energetics of 43 1,4-dihydrogenation reactions of polycyclic aromatic hydrocarbons and nitrogen-containing heterocycles as well as the 43 analogous Diels-Alder reactions with ethylene (C(2)H(4)) have been computed using B3LYP/6-31G(d) density functional theory (DFT). The transition state distortion energies are found to correlate with the activation energies of these reactions, even for cases when energies of reaction do not correlate with reactivities.
Mechanisms for the recently described reactions of isonitriles with carboxylic acids (Li, X.; Danishefsky, S. J. J. Am. Chem. Soc. 2008, 130, 5446) are explored with the B3LYP density functional method. The mechanism involves the formation of a carboxylate mixed formimidic anhydride intermediate via a concerted mechanism. This intermediate is then transformed to an N-formylamide by a concerted pseudopericyclic [1,3]-acyl shift. Mechanisms involving zwitterions or diradicals are discounted.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.