Summary of the most relevant computational dataa shown in Fig. 2–7. L and S descriptors denote large and small substituents, respectively.
| Reaction | 1a + 2a → 3aa | 1b + 2b → 3bb | 1b + 2c → 3bc | ||
|---|---|---|---|---|---|
| Rxn conditionsb | A | A | B | B | C |
| ΔGa(TSi) | 19.4 | 17.7 | 17.8 | 17.9 | 17.5 |
| ΔGrel[(Z)-2 − (E)-2] | 4.9 | 2.7 | 2.9 | 1.0 | 0.4 |
| ΔGa[(E)-TS1] | 11.9 | 9.6 | 10.1 | 15.1 | 19.6 |
| ΔGa[(Z)-TS1] | 12.3 | 8.1 | 8.7 | 15.1 | 18.4 |
| ΔGrel[(E)-INT − (Z)-INT] | −0.6 | −1.4 | −1.5 | 0.0 | −1.1 |
| ΔGa(TSR) | 22.6 | 36.1 | 36.7 | 9.9 | 7.6 |
| ΔGa(cis-TS2) | 5.7 | 13.0 | 12.9 | 0.2 | 0.1 |
| ΔGa(trans-TS2) | 3.2 | 8.9 | 8.6 | 3.9 | 1.9 |
| ΔGrxn(cis-3) | −33.9 | −26.7 | −30.6 | −28.8 | −32.8 |
| ΔGrxn(trans-3) | −34.2 | −67.8 | −28.2 | −69.0 | −30.2 |
a
Activation (ΔGa), relative (ΔGrel) and reaction (ΔGrxn) free energies calculated at the M06-2X(PCM)/def2-TZVPP level of theory, given in kcal mol−1.
b
Temperatures and solvents for conditions A–C are given in Scheme 3.