Overall, the reaction proceeds as postulated, with an endergonic C-H zincation to form 10 (+14.8 kcal/mol) proceeding as outlined in our previous report (via a transition state at +21.7 kcal/mol). is followed by a -bond metathesis phase that is effectively thermoneutral (+0.9 kcal/mol) with the overall process driven forward by exergonic dehydrocoupling to reform [9] + with loss of H2 (G = -16.9 kcal/mol). The overall process is therefore exergonic (G = -1.2 kcal/mol).