For the photochemical [1,3]-OH shift in 2-propen-1-01 a mechanism is proposed on the basis of the relaxation of the excited double bond toward a twisted geometry, accompanied by a separation of charge, leading to a planar [1,3]-OH shift. By means of semiempirical MNDO calculations followed by a limited (3 X 3) CI, one-dimensional potential energy surfaces for ground and excited states are calculated. It is shown that the proposed mechanism is strongly preferred to the mechanism predicted by the rules of conservation of orbital symmetry. It is to be expected that the presented results may be of general value in alkene photochemistry.
Dormans, G. J. M., Fransen, H. R., & Buck, H. M. (1984). A quantum chemical study on the mechanism of a photochemical [1,3]-hydroxyl shift in 2-propen-1-ol. Journal of the American Chemical Society, 106(5), 1213-1216. https://doi.org/10.1021/ja00317a007