J. Phys. Chem. B 2008, 112, 11-15
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ARTICLES Photodecarbonylation of r-Diketones: A Mechanistic Study of Reactions Leading to Acenes Rajib Mondal, Albert N. Okhrimenko, Bipin K. Shah, and Douglas C. Neckers* Center for Photochemical Sciences,1 Bowling Green State UniVersity, Bowling Green, Ohio 43403 ReceiVed: August 22, 2007; In Final Form: October 9, 2007
Poly(acene)s are significant compounds for various electronic applications. A clean, one-step synthesis involves R-diketones (2-4), which undergo facile Strating-Zwanenburg photodecarbonylation producing the corresponding poly(acene)s (i.e., anthracene, hexacene, and heptacene, respectively). Compounds 2-4 show weak fluorescence (λF ) ∼525-530 nm and ΦF ) ∼0.1-0.4%) and phosphorescence (λPh ) ∼565-570 nm) and have a small singlet-triplet energy gap (S1 - T1 gap, ∼4 kcal/mol) that facilitates rapid intersystem crossing from the singlet to the triplet state. Both the singlet states (τS ) ∼20-218 ps) and the triplet states (τT ) ∼370 ps to 350 ps and 350 ps and 370 ps and
