Selective Esterification of Phosphonic Acids †
Abstract
:1. Introduction
2. Results and Discussion
3. Materials and Methods
3.1. General
3.2. General Procedure for Esterification of Phosphonic Acid Using Various Alkoxy Group Donors
3.3. General Procedure for Esterification of Phosphonic Acids Using Triethyl Orthoacetate in Different Solvents
3.4. The Influence of Temperature on the Selectivity of Esterification Reaction of Butylphosphonic acid with Triethyl Orthoacetate
3.5. General Procedure for Selective Monoesterification of Phosphonic Acids 1 Using Triethyl Orthoacetate 2a Leading to Ethyl Hydrogen Phosphonates 3
3.6. General Procedure for Esterification of Phosphonic Acids 1 Using Triethyl Orthoacetate Leading to Diethyl Phosphonic Esters 4
3.6.1. Ethyl Hydrogen Butylphosphonate (3a)
3.6.2. Ethyl Hydrogen Benzylphosphonate (3b)
3.6.3. Ethyl Hydrogen Ethylphosphonate (3c)
3.6.4. Ethyl Hydrogen Vinylphosphonate (3d)
3.6.5. Ethyl Hydrogen Hexylphosphonate (3e)
3.6.6. Ethyl Hydrogen Dodecylphosphonate (3f)
3.6.7. Ethyl Hydrogen Phenylphosphonate (3g)
3.6.8. Ethyl Hydrogen (4-Methoxyphenyl)phosphonate (3h)
3.6.9. Ethyl Hydrogen [(4-Nitrophenyl)methyl]phosphonate (3j)
3.6.10. Ethyl Hydrogen [(4-Bromophenyl)methyl]phosphonate (3k)
3.6.11. Ethyl Hydrogen [(3-Bromophenyl)methyl]phosphonate (3l)
3.6.12. Diethyl Butylphosphonate (4a)
3.6.13. Diethyl Benzylphosphonate (4b)
3.6.14. Diethyl Ethylphosphonate (4c)
3.6.15. Diethyl Hexylphosphonate (4e)
3.6.16. Diethyl Dodecylphosphonate (4f)
3.6.17. Diethyl Phenylphosphonate (4g)
3.6.18. Diethyl (4-Methoxyphenyl)phosphonate (4h)
3.6.19. Diethyl [(4-Hydroxyphenyl)methyl]phosphonate (4i)
3.6.20. Diethyl [(4-Nitrophenyl)methyl]phosphonate (4j)
3.6.21. Diethyl [(4-Bromophenyl)methyl]phosphonate (4k)
3.6.22. Diethyl [(3-Bromophenyl)methyl]phosphonate (4l)
3.6.23. Tetraethyl [1,4-Phenylenebis(methylene)]bis(phosphonate) (4m)
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
Sample Availability
References
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Entry | Substrate | Donor | Conversion of 1 [%] 2 | Product Yield [%] 2 | |
---|---|---|---|---|---|
3 | 4 | ||||
1 | 1a | 2a | 98 | 84 | 3 |
2 | 2b | 25 | 25 | 0 | |
3 | 2c | 0 | 0 | 0 | |
4 | 2d | 0 | 0 | 0 | |
5 | 2e | 0 | 0 | 0 | |
6 | 2f | 0 | 0 | 0 | |
7 | 2g | 39 | 34 | 0 | |
8 | 2h | 24 | 23 | 1 | |
9 | 2i | 0 | 0 | 0 | |
10 | 2j | 0 | 0 | 0 | |
11 | 2k | 0 | 0 | 0 | |
12 | 2l | 0 | 0 | 0 | |
13 | 2m | 0 | 0 | 0 | |
14 | 2n | 0 | 0 | 0 | |
15 | 1b | 2a | 89 | 83 | 1 |
16 | 2b | 50 | 49 | 1 | |
17 | 2c | 0 | 0 | 0 | |
18 | 2d | 0 | 0 | 0 | |
19 | 2e | 0 | 0 | 0 | |
20 | 2f | 0 | 0 | 0 | |
21 | 2g | 89 | 83 | 6 | |
22 | 2h | 52 | 44 | 8 | |
23 | 2i | 0 | 0 | 0 | |
24 | 2j | 0 | 0 | 0 | |
25 | 2k | 0 | 0 | 0 | |
26 | 2l | 0 | 0 | 0 | |
27 | 2m | 0 | 0 | 0 | |
28 | 2n | 0 | 0 | 0 |
Entry | Solvent | Substrate 1a Conversion [%] 2 | Product Yield [%] 2 | Substrate 1b Conversion [%] 2 | Product Yield [%] 2 | ||
---|---|---|---|---|---|---|---|
3a | 4a | 3b | 4b | ||||
1 | MTBE | 89 | 87 | 2 | 90 | 85 | 5 |
2 | THF | 66 | 62 | 1 | 89 | 80 | 1 |
3 | DCM | 88 | 78 | 1 | 98 | 84 | 3 |
4 | EtOAc | 76 | 75 | 1 | 68 | 66 | 2 |
5 | MeCN | 71 | 65 | 2 | 50 | 41 | 2 |
6 | Me2CO | 15 | 10 | 0 | 3 | 2 | 1 |
7 | PhMe | 76 | 74 | 2 | 89 | 81 | 3 |
8 | Neat 3 | 95 | 89 | 5 | 95 | 88 | 7 |
9 | DMSO | 0 | 0 | 0 | 0 | 0 | 0 |
10 | DMF | 0 | 0 | 0 | 0 | 0 | 0 |
Entry | Temperature [°C] | Substrate 1a Conversion [%] 2 | Product Yield [%] 2 | |
---|---|---|---|---|
3a | 4a | |||
1 | 30 | 97 | 92 | 5 |
2 | 40 | >99 | 94 | 6 |
3 | 50 | 87 | 13 | |
4 | 60 | 73 | 27 | |
5 | 70 | 29 | 66 | |
6 | 80 | 21 | 79 | |
7 | 90 | 1 | 96 | |
8 | 100 | 0 | 95 |
Entry | R | Product | Conditions | Yield [%] 2 | 31P NMR [ppm] |
---|---|---|---|---|---|
1 | n-Butyl | 3a | 30 °C, 24 h | 98 | 29.1 |
2 | 4a | 90 °C, 24 h | 98 | 32.0 | |
3 | Benzyl | 3b | 30 °C, 48 h | 76 | 23.3 |
4 | 4b | 90 °C, 24 h | 98 | 26.5 | |
5 | Ethyl | 3c | 30 °C, 96 h | 89 | 30.2 |
6 | 4c | 90 °C, 24 h | 97 | 33.1 | |
7 | Vinyl | 3d | 25 °C, 24 h | 83 | 14.0 |
8 3 | 4d | 90 °C, 24 h | <1 | 16.9 | |
9 | n-Hexyl | 3e | 30 °C, 48 h | 93 | 28.9 |
10 | 4e | 90 °C, 24 h | 91 | 31.9 | |
11 | n-Dodecyl | 3f | 30 °C, 72 h | 89 | 28.9 |
12 | 4f | 90 °C, 24 h | 89 | 31.9 | |
13 | Phenyl | 3g | 30 °C, 24 h | 56 | 15.0 |
14 | 4g | 90 °C, 24 h | 98 | 17.8 | |
15 | 4-methoxyphenyl | 3h | 30 °C, 96 h | 65 | 15.5 |
16 | 4h | 90 °C, 24 h | 99 | 18.8 | |
17 4 | 4-hydroxybenzyl | 3i | 30 °C, 96 h | <1 | - |
18 | 4i | 90 °C, 24 h | 79 | 27.1 | |
19 | 4-nitrobenzyl | 3j | 40 °C, 24 h | 29 | 21.4 |
20 | 4j | 90 °C, 24 h | 99 | 24.9 | |
21 | 4-bromobenzyl | 3k | 30 °C, 24 h | 78 | 22.4 |
22 | 4k | 90 °C, 24 h | 75 | 25.8 | |
23 | 3-bromobenzyl | 3l | 30 °C, 48 h | 49 | 22.7 |
24 | 4l | 90 °C, 24 h | 74 | 25.9 | |
25 4 | p-xylylene | 3m | 30 °C, 48 h | <1 | - |
26 | 4m | 145 °C, 24 h | 99 | 26.5 |
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Trzepizur, D.; Brodzka, A.; Koszelewski, D.; Ostaszewski, R. Selective Esterification of Phosphonic Acids. Molecules 2021, 26, 5637. https://doi.org/10.3390/molecules26185637
Trzepizur D, Brodzka A, Koszelewski D, Ostaszewski R. Selective Esterification of Phosphonic Acids. Molecules. 2021; 26(18):5637. https://doi.org/10.3390/molecules26185637
Chicago/Turabian StyleTrzepizur, Damian, Anna Brodzka, Dominik Koszelewski, and Ryszard Ostaszewski. 2021. "Selective Esterification of Phosphonic Acids" Molecules 26, no. 18: 5637. https://doi.org/10.3390/molecules26185637