Fig. 6. Conformational dependence of IRC behaviour. An overlay of two conformations of β-TS1 for formation of the trans product for the substrates in entries 1 and 2 in the table inset in Fig. 5.54 The lowest energy conformation (orange, IRC leading to the fragmented product) and the higher energy conformation (green, IRC leading to the β-lactone product) differ only by rotation of the substituted phenyl ring. The Rh2(OAc)4 catalyst is represented as gray lines for clarity. Both structures were optimized at the B3LYP/6-31G(d), LANL2DZ level of theory.
