Table 2 Optimization of reaction conditions for deuterating α-amines
From: Photocatalyst-free photochemical deuteration via H/D exchange with D2O
| |||
|---|---|---|---|
Entry | Variation of standard conditions | Yield (%)a | D ratio (%)b |
1 | Without PhCOOMe | 98 | 47 |
2 | None | 99(99c) | 96 |
3 | 420 nm instead of 380 nm | 96 | 85 |
4 | thiol II instead of thiol I-d1 | 96 | <5 |
5 | thiol III instead of thiol I-d1 | 97 | 20 |
6 | thiol I-d1 (15 mol%) instead of thiol I-d1 (30 mol%) | 96 | 87 |
7 | MeCN instead of EtOAc | 18 | 97 |
8 | CHCl3 instead of EtOAc | 91 | 22 |
9 | Toluene instead EtOAc | 98 | 20 |
10 | 20 °C instead of 40 °C | 97 | 91 |
11 | 12 h instead of 24 h | 98 | 63 |
12 | 100 equiv of D2O instead of 40 equiv | 96 | 93 |
13 | Without thiol I-d1 or light | 99 | <5 |
