2-Hydroxyphenyl-1,3-dimethylbenzimidazolines. Formal two hydrogen atom-donors for photoinduced electron transfer reactions

Chemistry Letters

Volumn 33, Issue 1, 2004, Pages 18-19

  Hasegawa, Eietsu ^a   Chiba, Naoki ^a   Takahashi, Tomoya ^a   Takizawa, Shinya ^a   Kitayama, Takashi ^a   Suzuki, Toshio ^a  

^a NIIGATA UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

2 (2' HYDROXYPHENYL) 1,3 DIMETHYLBENZIMIDAZOLINE; 2 (4' HYDROXYPHENYL) 1,3 DIMETHYLBENZIMIDAZOLINE; CARBONYL DERIVATIVE; HYDROGEN; IMIDAZOLINE DERIVATIVE; UNCLASSIFIED DRUG;

ARTICLE; ATOM; ELECTRON TRANSPORT; PHOTOREACTIVITY;

EID: 2042469443     PISSN: 03667022     EISSN: None     Source Type: Journal    
DOI: 10.1246/cl.2004.18     Document Type: Article

References (16)

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6. 2 prepurged solution (4.0 mL) of epoxy ketone 1a (0.40 mmol) and DMPBI or HPDMBI (0.48 mmol) in a Pyrex tube was irradiated with a 500-W Xe-lamp for 1 h. In the case of redox-sensitization for 1b-1e, a solution containing BDMAP (0.02 mmol), 1b-1e, and HPDMBI or ADMBI similarly prepared as above was irradiated through a colored glass filter cutting the light below 340 nm for 3 h. The photolysates were concentrated and then subjected to silica gel column or TLC separation. In the case using DMF as a reaction solvent, extraction of the photolysate with EtOAc was needed. BDMAP sensitized reactions of 4 and 6 with o-HPDMBI were similarly performed. The products 2, 3, 5, and 6 were identified by their NMR and IR spectra. Oxidation products derived from HPDMBI, although not completely characterized yet, are considered to possess both benzimidazolium and phenoxide structures on the basis of their NMR and IR spectra.
7. 2
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