A triphenylphosphine mediated photo-rearrangement and methanol addition of aryl chalcones to 1-propanones.
Aryl chalcones rearrange and add methanol to give substituted propane-1-ones upon UV-A irradiation in the presence of PPh3. We propose two possible mechanisms for this photo-rearrangement. The reaction involves either the formation of a phosphine-carbonyl intermediate, nucleophilic addition of MeOH and 1,2-aryl migration or the formation of ylide and carbene intermediates. The intermediates trapped from the reaction mixture support the first mechanistic hypothesis.
Institute of Organic Chemistry, University of Regensburg, Universitätstr. 31, 93053 Regensburg, Germany. Burkhard.Koenig@ur.de.
Qiu
Q
Sun
Chang Jiang
CJ
Yao
Burkhard
B
König