Intorp Sebastian N, Hodecker Manuel, Müller Matthias, Tverskoy Olena, Rosenkranz Marco, Dmitrieva Evgenia, Popov Alexey A, Rominger Frank, Freudenberg Jan, Dreuw Andreas, Bunz Uwe H F
Organisch-Chemisches Institut, Ruprecht-Karls-Universität, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany.
Interdisziplinäres Zentrum für Wissenschaftliches Rechnen, Ruprecht Karls-Universität Heidelberg, Im Neuenheimer Feld 205, 69120, Heidelberg, Germany.
Angew Chem Int Ed Engl. 2020 Jul 20;59(30):12396-12401. doi: 10.1002/anie.201915977. Epub 2020 Apr 28.
Quinoidal azaacenes with almost pure diradical character (y=0.95 to y=0.99) were synthesized. All compounds exhibit paramagnetic behavior investigated by EPR and NMR spectroscopy, and SQUID measurements, revealing thermally populated triplet states with an extremely low-energy gap ΔE of 0.58 to 1.0 kcal mol . The species are persistent in solution (half-life≈14-21 h) and in the solid state they are stable for weeks.
合成了具有几乎纯双自由基特征（y = 0.95至y = 0.99）的醌型氮杂并苯。所有化合物均表现出顺磁行为，通过电子顺磁共振（EPR）、核磁共振（NMR）光谱以及超导量子干涉仪（SQUID）测量进行研究，结果表明存在热激发的三重态，其能隙ΔE极低，为0.58至1.0千卡·摩尔⁻¹。这些物种在溶液中具有持久性（半衰期≈14 - 21小时），在固态下可稳定存在数周。
