Görner Helmut
Max-Planck-Institut für Bioanorganische Chemie, Mülheim an der Ruhr, Germany.
Photochem Photobiol. 2005 Mar-Apr;81(2):376-83. doi: 10.1562/2004-08-11-RA-270.
The photochemistry of lapachol and other 1,4-naphthoquinone (NQ) derivatives, e.g. 2-methoxy-1,4-naphthoquinone (MeONQ), 2-hydroxy-1,4-naphthoquinone (2-HONQ) or 5-hydroxy-1,4-naphthoquinone (5-HONQ) and 2-methyl-5-hydroxy-1,4-naphthoquinone (P-NQ) in solution at room temperature was studied by ultraviolet-visible spectroscopy after nanosecond laser pulses at 248 nm. The triplet state and semiquinone radicals were observed for MeONQ, HONQ and P-NQ, whereas for lapachol, intramolecular H-atom and charge transfer processes take place, as in the case of vitamin K1. The photoinduced reaction of NQ into HONQ is initiated by nucleophilic water addition to the triplet state, and for the secondary reactions, a modified mechanism is proposed.
通过在248nm处的纳秒激光脉冲后，利用紫外可见光谱研究了拉帕醇和其他1,4-萘醌（NQ）衍生物，如2-甲氧基-1,4-萘醌（MeONQ）、2-羟基-1,4-萘醌（2-HONQ）或5-羟基-1,4-萘醌（5-HONQ）以及2-甲基-5-羟基-1,4-萘醌（P-NQ）在室温溶液中的光化学。在MeONQ、HONQ和P-NQ中观察到了三重态和半醌自由基，而对于拉帕醇，如同维生素K1的情况一样，发生了分子内氢原子和电荷转移过程。NQ光诱导转化为HONQ是由亲核水加成到三重态引发的，并且对于二级反应，提出了一种改进的机制。
