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Updated: Jul 4, 2026

Electroactive Polymer Nanoparticles Exhibiting Photothermal Properties
Published on: January 8, 2016
Aryl-aryl bond formation by flash vacuum pyrolysis of benzannulated thiopyrans
Aaron W Amick1, Atsushi Wakamiya, Lawrence T Scott
1Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467-3860, USA.
Abstract:
In contrast to fully unsaturated 7-membered ring sulfur heterocycles (thiepines), some of which extrude sulfur and give the ring-contracted hydrocarbon even at room temperature in solution, benzannulated thiopyrans (6-membered sulfur heterocycles) require flash vacuum pyrolysis (FVP) conditions in the gas phase at temperatures in the range of 1000-1200 degrees C to promote the corresponding reaction. Thus, FVP of benzo[kl]thioxanthene (1) gives fluoranthene, and naphtho[2,1,8,7-klmn]thioxanthene (6) gives benzo[ghi]fluoranthene (7). FVP of thioxanthone (9) gives fluorenone (10), together with lesser amounts of dibenzo[b,d]thiophene (11), from competing decarbonylation.
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