Photochemistry of di-Schiff bases and related compounds

✍ Scribed by Tauer, Erich ;Grellmann, Karl-Heinz ;Heinrich, Angelika

• Book ID: 102367341
• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 440 KB
• Volume: 1995
• Category: Article
• ISSN: 0947-3440
• DOI: 10.1002/jlac.199519950492

✦ Synopsis

The photochemical properties of the di-Schiff base 2 have been investigated. The first reaction step of 2 in 2-propanol or in cyclohexane is an intramolecular photoreductive coupling affording the diazocine meso-4. Subsequent photoreactions of meso-4 in 2-propanol are studied. In concentrated solutions of phenanthridine in cyclohexane a photodimerization takes place during which two CH bonds are broken and two NH bonds are formed. The photodimer reconverts with high quantum yield quantitatively to the monomer.

Based on these considerations, we tentatively assign meso-4 to the primary photoproduct. Its 'H-NMR spectrum shows, besides the low-field multiplet of 16 aromatic protons, three broad singlets at 6 = 3.7 (2H, NH), 4.25 (lH,