Figure 11. Intrinsic reaction coordinate (IRC) curve of TS3 and
energy level diagram of elementary reaction 3.
From the structure, it can be seen that H(30) of 3a’ rotated.
As shown in Figure 13, the dihedral angle C(8)–C(7)–O(14)–H(30) was
flexibly scanned in 360 steps with a step length of 1°. Configuration
3a0 of the product has the lowest energy and was further
optimized to obtain the final product, 3a . The geometries of
the stationary points are shown in Figure 12.