We highlight that the transition state geometry of β-hydride transfer on the 3CN Ga site is fundamentally different from the step occurring on a transition metal single site. In the transition states on Ni 2+ or Cr 3+ single sites, the hydrogen atom being transferred is close to the metal center, and this interaction contributes to the stabilization of transition state. In the transition state on a 3CN Ga site ( ‡ a ), however, the hydrogen atom being transferred does not interact closely with the Ga atom, suggesting that Ga does not directly activate the C-H bond. Nevertheless, a low barrier is observed. This geometry was reported for early transition metal-based Ziegler-Natta catalysts, with an associated low barrier being attributed to a pseudo-hydrogen bond effect. Our results suggest that a similar effect may extend to main group single sites, such as Ga.