Table 2 Scope of Cu(II)-catalyzed hetero-Diels–Alder reactionsa
From: Divergent synthesis of chiral cyclic azides via asymmetric cycloaddition reactions of vinyl azides
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|---|---|---|---|---|---|---|
Entry | 1 (R1, R2) | 2 (R3) | 3 | endo/exo | Yield (%)b | ee (%)c |
1 | 1a (Ph, Me) | 2a (Ph) | 3a | 80/20 | 89 | >99 |
2 | 1a | 2b (4-ClC6H4) | 3b | 80/20 | 82 | 97 |
3 | 1a | 2c (4-FC6H4) | 3c | 78/22 | 84 | 96 |
4 | 1a | 2d (4-BrC6H4) | 3d | 75/25 | 85 | 99 |
5 | 1a | 2e (4-MeOC6H4) | 3e | 60/40 | 94 | 72 |
6 | 1a | 2f (4-MeC6H4) | 3f | 90/10 | 74 | 95 |
7 | 1a | 2g (4-tBuC6H4) | 3g | 93/7 | 66 | 98 |
8 | 1a | 2h (4-PhC6H4) | 3h | 74/26 | 80 | 97 |
9 | 1a | 2i (3-ClC6H4) | 3i | 84/16 | 74 | 98 |
10 | 1a | 2j (3-MeC6H4) | 3j | 91/9 | 54 | 97.5 |
11 | 1a | 2k (2-naphthyl) | 3k | 78/22 | 88 | 97 |
12 | 1a | 2l (3-thienyl) | 3l | 72/28 | 81 | 90 |
13 | 1b (Ph, Et) | 2a (Ph) | 3m | 86/14 | 82 | 99.5 |
14 | 1c (Ph, iPr) | 2a (Ph) | 3n | 88/12 | 80 | 98 |
15 | 1d (4-MeC6H4, Bn) | 2a (Ph) | 3o | 91/9 | 58 | 98 |
16 | 1e (4-ClC6H4, Me) | 2a (Ph) | 3p | 90/10 | 78 | 97 |
17 | 1f (4-BrC6H4, Me) | 2a (Ph) | 3q | 90/10 | 75 | 97 |
18 | 1g (4-FC6H4, Me) | 2a (Ph) | 3r | 84/16 | 86 | 97 |
19 | 1h (4-MeC6H4, Me) | 2a (Ph) | 3s | 89/11 | 94 | 99 |
20 | 1i (4-MeOC6H4, Me) | 2a (Ph) | 3t | 93/7 | 58 | 98 |
21 | 1j (3-BrC6H4, Me) | 2a (Ph) | 3u | 90/10 | 67 | 96.7 |
22 | 1k (2-naphthyl, Me) | 2a (Ph) | 3v | 90/10 | 81 | >99 |
23 | 1l (3-thienyl, Me) | 2a (Ph) | 3w | 84/16 | 86 | 97 |
