Table 1 Substituent effects on NHC-Ni catalyzed diastereodivergent reductive hydroalkenylation of enyne with propargyl Z a.
From: NHC-Ni catalyzed 1,3- and 1,4-diastereodivergent heterocycle synthesis from hetero-substituted enyne
| ||||||||
|---|---|---|---|---|---|---|---|---|
Entry | 1 | Z | R1 | Ligand | Product | Syn:Anti 3:3′ | Syn:Anti 4:4′ | Yield (%) |
1 | 1a | O | Ph | IPr SIPr | 3a | >95:5 92:8 | n.a. | 74 43 |
2 | 1b | Me | IPr | 3b | >95:5 | 78 | ||
3 | 1c | NH | Ph | IPr | 3c | 96:4c | n.a. | 81 |
4 | 1d | Me | IPr | 3d | >95:5 | 62 | ||
5 | 1e | NMs | Ph | IPr | 4′e | n.a. | 6:94c | 84 |
SIPr | 18:82c | 48 | ||||||
IMes | n.a. | 0 | ||||||
PCy3b | 19:81c | 11 | ||||||
6 | 1 f | NMs | Me | IPr | 4′d | n.a. | 12:88 | 58 |
7 | 1 g | NTs | Ph | IPr | 4′g | n.a. | 40:60 | 30 |
8 | 1 h | NBn | IPr | 3i | 88:12 | n.a. | 48 | |
