Table 3. Yields and Selectivity Obtained for Endo/Exo Adducts from the Reaction between Cyclopentadiene with Ester 2 Using DES 1, 7, and 8 and for Ester 3 Using DES 1.
| DES (1:2) | 4a:4b ratiob. | yield % | retention time (min) | 5a:5b ratiob | yield % | retention time (min) |
|---|---|---|---|---|---|---|
| 1 | 2.7:1 | 89 | 15.01:14.91 | 2.6:1 | 78 | 13.50:12.91 |
| a7 | 2.8:1 | 64 | 15.26:15.16 | |||
| a8 | 2.8:1 | 68 | 15.26:15.15 |
a
Diels–Alder reactions using ester 3 were not carried out on DESs 7 and 8 based on the results achieved with ester 2.
b
The ratios between the adducts were determined by GC-FID with an injection temperature of 230 °C. Reactions were performed at 25 °C for 72 h.