Memory of Chirality in Photochemistry.
The helical-chiral character of the diradical intermediate 2, which cyclizes quicker than it equilibrates, explains the memory effect of chirality that occurs during the enantioselective photocyclization of alanine derivative 1 to give the proline derivative 3. Ts=H(3)CC(6)H(4)SO(2).
Giese
B
Department of Chemistry, University of Basel, St. Johanns-Ring 19, CH-4056 Basel (Switzerland).
Wettstein
P
Stähelin
C
Barbosa
F
Neuburger
M
Zehnder
M
Wessig
P