Asymmetric Photochemistry and Photochirogenesis

Abstract

One of the most interesting phenomena on Earth is the chirality of biomolecules, the origin of which remains unknown. A challenge arising from this phenomenon is the selective, atom-economic synthesis of enantiomerically pure target molecules from nonchiral starting materials. Herein, new developments in the field of asymmetric photochemistry and photochirogenesis are described with special emphasis on absolute asymmetric synthesis. In this context, the elucidation of the ultimate cause of homochirality phenomena on earth and the possible correlation with physicochemical parameters are also presented.

Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)

“…Asymmetric induction may be achieved by the use of chiral reagents, a chiral environment, or circularly polarized light [26].…”

Radiopolymerization of β(-)pinene: A case of chiral amplification

“…There are many hypothesis on how chirality appeared in a prebiotic world and some of these hypothesis are also supported by experimental facts (Palyi et al, 1999;. For instance, asymmetric photolysis of racemic substrates with circularly polarized light is a commonly accepted process which may have led to enantiomeric excess under prebiotic conditions (Griesbeck and Meierhenrich, 2002;Jorissen and Cerf, 2002). It is even thought that such processes of asymmetric photolysis occur in the circumstellar and interstellar medium due to the action of circularly polarized UV light emitted by stars (Bailey et al, 1998).…”

Spin effects in intramolecular electron transfer in naproxen-N-methylpyrrolidine dyad

“…At present, there are only a few examples of the influence of chirality on photochemical processes [4,5,6,7,8,9,10,11,12]. The difference in the radical transformation of the (R) and (S) enantiomers of 2-phenylpropionic acid in the reaction with 4-methyl-2-quinolinecarbonitrile was detected using spin chemistry methods [13].…”