Table 7.
Relative stabilities of alkyne/allene isomers at −20 °C
| R | X | ΔG (allene–alkyne, kcal/mol) | experimental alkyne:allene |
|---|---|---|---|
| H | Ph | −3.7 | 30:70 |
| H | 6-MeO-naphth-2-yl | −4.3 | 20:80 |
| H | thiophen-2-yl | −3.0 | 61:39 |
| H | N-phthalimido | −6.5 | 6:94 |
Relative stabilities of alkyne/allene isomers at −20 °C
| R | X | ΔG (allene–alkyne, kcal/mol) | experimental alkyne:allene |
|---|---|---|---|
| H | Ph | −3.7 | 30:70 |
| H | 6-MeO-naphth-2-yl | −4.3 | 20:80 |
| H | thiophen-2-yl | −3.0 | 61:39 |
| H | N-phthalimido | −6.5 | 6:94 |