Table 1. Structural Effects on the T-Dependence of Hydride KIEs of the Hydride-Transfer Reactions in Acetonitrilea.
| entries | donor(Don-H) | acceptorb(Acc) | k2H25 °C(M–1s–1) | ΔHH‡(kcal/mol) | ΔSH‡(cal/mol·K) | KIE25 °C | ΔEa(kcal/mol) |
|---|---|---|---|---|---|---|---|
| System (1) | |||||||
| 1c | MAH | PhXn+ | 4.10(0.03) × 102 | 7.51(0.05) | –21.6(0.2) | 4.08 (0.03) | 0.88 (0.05) |
| 2 | PAH | PhXn+ | 1.43(0.02) × 103 | 5.70(0.07) | –25.2(0.2) | 4.60 (0.05) | 0.94 (0.08) |
| 3 | BAH | PhXn+ | 3.79(0.02) × 102 | 6.59(0.03) | –24.8(0.1) | 4.26 (0.03) | 0.88 (0.05) |
| System (2) | |||||||
| 4d | HEH | MA+ | 1.56(0.01) × 102 | 5.71(0.03) | –29.5(0.1) | 4.92 (0.04) | 0.95 (0.10) |
| 5 | HEH | PA+ | 1.57(0.01) × 102 | 5.54(0.04) | –30.1(0.1) | 4.92 (0.03) | 1.20 (0.10) |
| 6 | HEH | HA+ | 1.53(0.002) × 102 | 5.71(0.03) | –29.6(0.1) | 5.02 (0.01) | 1.07 (0.06) |
| 7 | HEH | BA+ | 5.73(0.03) × 102 | 4.78(0.12) | –30.0(0.4) | 4.53 (0.04) | 1.01 (0.12) |
| System (3) | |||||||
| 8 | i-PrOH | PhXn+ | 2.02(0.05) × 10–5e | 1.37(0.02) × 10 | –34.1(0.6) | 3.63 (0.23)d | 0.83 (0.27) |
| 9 | i-PrOH-β,β-d6 | PhXn+ | 2.01(0.05) × 10–5e | 1.34(0.02) × 10 | –34.9(0.5) | 3.64 (0.16)d | 0.80 (0.19) |
| 10 | c-HexOH | PhXn+ | 2.68(0.01) × 10–5e | 1.35(0.02) × 10 | –34.2(0.7) | 3.68 (0.16)d | 0.90 (0.27) |
| 11 | 4-HepOH | PhXn+ | 5.63(0.01) × 10–6e | 1.36(0.02) × 10 | –36.8(0.7) | 3.31 (0.06)d | 0.64 (0.35) |
| System (4) | |||||||
| 12c | DMPBIH | MA+ | 2.12(0.01) × 102 | 7.20(0.07) | –23.9(0.2) | 3.57 (0.03) | 0.43 (0.15) |
| 13 | DMPBIH | PA+ | 1.28(0.01) × 102 | 7.07(0.19) | –25.1(0.6) | 3.32 (0.04) | –0.02 (0.35) |
| 14 | DMPBIH | HA+ | 1.36(0.01) × 102 | 7.23(0.18) | –24.5(0.6) | 3.39 (0.03) | –0.04 (0.30) |
| 15 | DMPBIH | BA+ | 5.78(0.04) × 102 | 6.36(0.09) | –24.6(0.3) | 3.10 (0.04) | 0.40 (0.22) |