Memory effect of chirality in the photocyclization of modified dipeptides

✍ Scribed by Stefan Sauer; Andreas Schumacher; Frédérique Barbosa; Bernd Giese

• Publisher: Elsevier Science
• Year: 1998
• Tongue: French
• Weight: 209 KB
• Volume: 39
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(98)00621-2

✦ Synopsis

Photocyclizations of dipeptides 5 and 8 occur mainly with retention of configuration at the stereogenic center of alanine. This memory effect of chirality is explained by a hindered rotation in the two intermediate biradicals 9 and 10 that slows down the equilibration of the radicals.