Table 4. Catalyst Optimization for the Direct Guanylation of 24.
| entrya | catalyst | equiv catalyst | conversion (%) |
|---|---|---|---|
| 1 | Sc(OTf)3 | 0.1 | 38 |
| 2 | Bi(OTf)3 | 0.1 | 34 |
| 3 | Y(OTf)3 | 0.1 | 25 |
| 4 | HCl | 1.0 | 8 |
| 5 | HNO3 | 1.0 | 40 |
| 6 | AcOH | 1.0 | 11 |
Aniline 28 (0.08 mmol), 1.2 equiv of NH2CN, 1.0 M, 72 h, MeCN/iPrOH 1:1 v/v.
