Applications of Bolm’s Ligand in Enantioselective Synthesis
Abstract
1. Introduction
2. Bolm’s Ligand
2.1. Bolm’s Ligand Properties and Synthesis
2.2. Alkylation and Allylation of Aldehydes
2.3. Conjugate Addition
2.4. Opening of Meso-Epoxides
2.5. Mukaiyama Aldol Reaction
2.6. Hydroxymethylation
2.7. α-Amination of β-Ketocarbonyl Compounds
2.8. C-H Functionalization of Indole
2.9. Diels–Alder Reaction
2.10. Other Applications
3. Conclusions
Author Contributions
Funding
Conflicts of Interest
References and Note
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Entry | 4 or 5a | Zn(OH)2 (mol%) | (S,S)-1 (mol%) | MeCN/H2O | Yield (%) | 6/7 | dr (syn/anti) | ee (syn) (%) |
---|---|---|---|---|---|---|---|---|
1 | 4 | - | - | 4/1 | 77 | 5/95 | - | - |
2 | 5a | 10 | - | 4/1 | 86 | 45/55 | 70/30 | - |
3 | 5a | 10 | 12 | 7/3 | 92 | >99/1 | 91/9 | 71 |
Entry | R1 | R2 | Zn(OH)2 (mol%) | (S,S)-1 (mol%) | Yield (%) | dr (syn/anti) | ee (syn) (%) | ||
---|---|---|---|---|---|---|---|---|---|
1 | PhCH2CH2 | 2b | Me | 5a | 5 | 6 | 94 | 83/17 | 85 |
2 | PhCH2CH2 | 2b | Et | 5b | 5 | 6 | 96 | 75/25 | 91 |
3 | PhCH2CH2 | 2b | iBu | 5c | 5 | 6 | 95 | 75/25 | 91 |
4 | PhCH2CH2 | 2b | Cl | 5d | 3 | 3.6 | 92 | 93/7 | 95 |
5 | Ph | 2a | Cl | 5d | 5 | 6 | 92 | 96/4 | 88 |
6 | 4-MeC6H4 | 2c | Cl | 5d | 3 | 3.6 | 91 | 96/4 | 87 |
7 | 4-BrC6H4 | 2d | Cl | 5d | 7.5 | 9 | quant | 95/5 | 85 |
8 | 1-naphthyl | 2e | Cl | 5d | 5 | 6 | 94 | 93/7 | 85 |
9 | CH3(CH2)10 | 2f | Cl | 5d | 2 | 2.4 | 92 | 93/7 | 93 |
Entry | Solvent 1 | T (°C) | c (M) | Yield (%) | ee (%) |
---|---|---|---|---|---|
1 | DCM | 10 | 0.08 | 22 | 53 |
2 | DCM | 20 | 0.08 | 61 | 80 |
3 | DCM | 30 | 0.08 | 98 | 81 |
4 | PhMe | 10 | 0.08 | quant. | 5 |
5 | MeCN/DCM | 30 | 0.08 | 76 | 8 |
6 | DCE | 30 | 0.08 | 94 | 84 |
7 | DCE | 30 | 0.04 | 96 | 89 |
8 | DCE | 40 | 0.02 | 94 | 92 |
Entry | Sc(OTf)3 (mol%) | 1 (mol%) | Base (mol%) | T (°C) | Yield (%) | ee (%) |
---|---|---|---|---|---|---|
1 | 2 | 5 (R,R) | - | 30 | 46 | 57 (R) |
2 | 1 | 2 (R,R) | NaOH (3) | 30 | 95 | 91 (R) |
3 | 1 | 1.2 (S,S) | Pyridine (10) | r.t. | 92 | 93 (S) |
Entry | R | X | Cu-Source | (mol%) | (S,S)-1 (mol%) | Additive (mol%) | T (°C) | Yield (%) | ee (%) |
---|---|---|---|---|---|---|---|---|---|
1 | Ph | O | Cu(OH)2 | 5 | 6 | AcOH (6) | 5 | 95 | 99 |
2 | Ph | O | Cu(OAc)2 | 5 | 6 | MeOH (100) | r.t. | 92 | 92 |
3 | Ph | O | Cu powder | 10 | 12 | - | 30 | 92 | 83 |
4 | Ph | NBn | Cu(OAc)2 | 5 | 6 | - | r.t. | 91 | >99 |
5 | PhCH=CH | O | Cu(OAc)2 | 5 | 6 | - | 5 | 91 | 91 |
Entry | Cu-Source | Additive (mol%) | Yield (%) | 27/28 | ee (%) |
---|---|---|---|---|---|
1 | Cu(OH)2 | - | 81 | <1/99 | 76 |
2 | Cu(OH)2 | AcOH (6 mol%) | 92 | >99/1 | 87 |
3 | Cu(OAc)2 | - | 94 | >99/1 | 91 |
Entry | X | R | 30–34 | (eq.) | M-source 1 | (mol%) | 1 (mol%) | Additive (mol%) | Solvent | Yield (%) | ee (%) |
---|---|---|---|---|---|---|---|---|---|---|---|
1 | NH | H | 30 | 1 | Sc(OTf)3 | 10 | 10 (R,R) | - | DCM | 95 | 93 (R,R) |
2 | NH | H | 30 | 1 | Sc(DS)3 | 1 | 1.2 (S,S) | - | H2O | 89 | 91 (S,S) |
3 | NH | H | 30 | 1.5 | Sc(OTf)3 | 10 | 12 (S,S) | - | DCM | 85 | 93 (S,S) |
4 | NH | H | 30 | 1.5 | Sc(UDST)3 | 10 | 12 (S,S) | - | H2O | 87 | 95 (S,S) |
5 | NH | H | 30 | 1.5 | Cu(OTf)2 | 10 | 12 (S,S) | - | DCM | 18 | 80 (R,R) |
6 | NH | H | 30 | 1.5 | Cu(UDST)2 | 10 | 12 (S,S) | - | H2O | 82 | 80 (R,R) |
7 | NH | H | 30 | 1.5 | Zn(OTf)2 | 10 | 12 (S,S) | - | DCM | 60 | 90 (R,R) |
8 | NH | H | 30 | 1.5 | Zn(UDST)2 | 10 | 12 (S,S) | - | H2O | 97 | 92 (R,R) |
9 | NH | H | 30 | 1 | Zn(OTf)2 | 5 | 5 (R,R) | NaDS (5 mol%) | H2O | 97 | 90 (S,S) |
10 | NH | H | 30 | 1 | ZrCl4 | 5 | 10 (R,R) | NaDS (20 mol%) | H2O | 55 | 22 (R,R) |
11 | NH | H | 30 | 2 | In(OTf)3 | 10 | 10 (R,R) | - | DCM | 69 | 89 (R,R) |
12 | NH | H | 30 | 1 | Fe(ClO4)2·6H2O | 5 | 6 (S,S) | - | DCM | 90 | 95 (S,S) |
13 | CH2O | MeO | 31 | 2 | Sc(OTf)3 | 10 | 10 (R,R) | - | DCM | 82 | 97 (R,R) |
14 | CH2O | Br | 32 | 1 | Sc(DS)3 | 10 | 12 (S,S) | - | H2O | 34 | 86 (S,S) |
15 | S | H | 33 | 3 | Sc(OTf)3 | 10 | 12 (S,S) | - | DCM | 84 | 94 (S,S) |
16 | S | H | 33 | 3 | Sc(DS)3 | 10 | 12 (S,S) | - | H2O | 73 | 89 (S,S) |
17 | S | H | 33 | 1.5 | InBr3 | 10 | 11 (R,R) | - | DCM | 81 | 96 (R,R) |
18 | Se | H | 34 | 3 | Sc(OTf)3 | 10 | 10 (R,R) | - | DCM | 77 | 93 (R,R) |
Entry | 42 (eq.) | M-source (mol%) | (S,S)-1 (mol%) | Solvent | Yield (%) | ee (%) | |
---|---|---|---|---|---|---|---|
1 | 1.2 | Sc(OTf)3 | 10 | 12 | DCM | Traces | - |
2 | 1.1 | Sc(DS)3 | 5 | 6 | H2O | 85 | 93 (R,R) |
3 | 1.2 | Sc(UDST)3 | 10 | 12 | H2O | 69 | 92 (R,R) |
4 | 1.2 | Cu(OTf)2 | 10 | 12 | DCM | 60 | 86 (S,S) |
5 | 1.2 | Cu(UDST)2 | 10 | 12 | H2O | 80 | 96 (S,S) |
6 | 1.2 | Zn(OTf)2 | 10 | 12 | DCM | Traces | - |
7 | 1.2 | Zn(UDST)2 | 10 | 12 | H2O | 8 | 80 (S,S) |
8 1 | 1.2 | Fe(ClO4)2·6H2O | 5 | 6 | DCM | 90 | >99 (R,R) |
Silyl Enol Ether | Aldehyde | ||
---|---|---|---|
R2 = Bulky | R2 = Non-Bulky | ||
R1 | Electron Rich | Electron Poor | |
Neutral | A | B | C |
EDG | A | C | C |
EWG | A | B | C |
Entry | R | M-source 1 | (mol%) | (S,S)-1 (mol%) | Additive | Solvent | T (°C) | Yield (%) | ee (%) |
---|---|---|---|---|---|---|---|---|---|
1 | H | Sc(OTf)3 | 10 | 12 | - | DCM | −20 | 80 | 90 |
2 | H | Bi(OTf)3 | 1 | 3 | 2,2′-bipyridine (5 mol%) | H2O | 0 | 93 | 91 |
3 | Me | Sc(DS)3 | 10 | 12 | Triton® X-705 | H2O | r.t. | 73 | 90 |
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Bednářová, E.; Malatinec, Š.; Kotora, M. Applications of Bolm’s Ligand in Enantioselective Synthesis. Molecules 2020, 25, 958. https://doi.org/10.3390/molecules25040958
Bednářová E, Malatinec Š, Kotora M. Applications of Bolm’s Ligand in Enantioselective Synthesis. Molecules. 2020; 25(4):958. https://doi.org/10.3390/molecules25040958
Chicago/Turabian StyleBednářová, Eva, Štefan Malatinec, and Martin Kotora. 2020. "Applications of Bolm’s Ligand in Enantioselective Synthesis" Molecules 25, no. 4: 958. https://doi.org/10.3390/molecules25040958
APA StyleBednářová, E., Malatinec, Š., & Kotora, M. (2020). Applications of Bolm’s Ligand in Enantioselective Synthesis. Molecules, 25(4), 958. https://doi.org/10.3390/molecules25040958