Procaine: Difference between revisions
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===Synthesis=== | ===Synthesis=== | ||
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Procaine can be synthesized in two ways. The first consists of the direct reaction of the [[4-aminobenzoic acid]] ethyl ester with [[diethylethanolamine|2-diethylaminoethanol]] in the presence of sodium ethoxide. The second is by oxidizing [[4-nitrotoluene]] to [[4-nitrobenzoic acid]], which is further reacted with [[thionyl chloride]], the resulting acid chloride is then esterified with [[ | Procaine can be synthesized in two ways. The first consists of the direct reaction of the [[4-aminobenzoic acid]] ethyl ester with [[diethylethanolamine|2-diethylaminoethanol]] in the presence of sodium ethoxide. The second is by oxidizing [[4-nitrotoluene]] to [[4-nitrobenzoic acid]], which is further reacted with [[thionyl chloride]], the resulting acid chloride is then esterified with [[2-diethylaminoethanol]]. Finally, the nitro group is reduced by hydrogenation over Raney nickel catalyst.<ref>{{cite web|url=https://en.wikipedia.org/wiki/Procaine#Synthesis|title=Wikipedia: Procaine#Synthesis}}</ref> | ||
[[4-nitrobenzoyl chloride]] is prepared by oxidizing [[4-nitrotoluene]] by boiling with [[sodium dichromate]] and [[sulfuric acid]], and treating the resulting [[4-nitrobenzoic acid]] with [[phosphorus pentachloride]]. The product is fractionally separated by distillation into [[phosphorus oxychloride]] and [[4-nitrobenzoyl chloride]]. 117 g of [[2-(Diethylamino)ethan-1-ol | [[4-nitrobenzoyl chloride]] is prepared by oxidizing [[4-nitrotoluene]] by boiling with [[sodium dichromate]] and [[sulfuric acid]], and treating the resulting [[4-nitrobenzoic acid]] with [[phosphorus pentachloride]]. The product is fractionally separated by distillation into [[phosphorus oxychloride]] and [[4-nitrobenzoyl chloride]]. 117 g of [[2-(Diethylamino)ethan-1-ol | ||
Revision as of 00:34, 8 December 2024
| Chemical formula | C13H20N2O2 |
|---|---|
| Molar Mass(g/mol) | 236.31 |
| Melting Point(°C) | 155-156 |
| NFPA 704 |  0
0
|
Uses
Primary
- Pharm: WHO LEM adjunct of penicillin: procaine penicillin
- Pharm: local anesthetic
Natural occurrence
- does not occur naturally
Hazards
Production
Synthesis
rough text
Procaine can be synthesized in two ways. The first consists of the direct reaction of the 4-aminobenzoic acid ethyl ester with 2-diethylaminoethanol in the presence of sodium ethoxide. The second is by oxidizing 4-nitrotoluene to 4-nitrobenzoic acid, which is further reacted with thionyl chloride, the resulting acid chloride is then esterified with 2-diethylaminoethanol. Finally, the nitro group is reduced by hydrogenation over Raney nickel catalyst.[1]
4-nitrobenzoyl chloride is prepared by oxidizing 4-nitrotoluene by boiling with sodium dichromate and sulfuric acid, and treating the resulting 4-nitrobenzoic acid with phosphorus pentachloride. The product is fractionally separated by distillation into phosphorus oxychloride and 4-nitrobenzoyl chloride. 117 g of [[2-(Diethylamino)ethan-1-ol
]] are mixed with 185.4 g of 4-nitrobenzoyl chloride. The reaction, which takes place spontaneously, is completed by heating the mixture for 2 hours at 120° C. The solid reaction product consists of the of para-nitrobenzoyl diethylethanolamine hydrochloride, which is dissolved in 800 ml of diluted hydrochloric acid and treated gradually with 240 g of granulated tin, the temperature being kept at 35-40° C. After reduction is completed the solution is saturated with hydrogen sulfide in order to remove tin. Then the solution is made alkaline with sodium carbonate, when the base separates as an oil which presently crystallizes. The mass is separated and recrystallized from dilute ethanol, from which crystals containing 2 molecules of water and melting at 51° C are obtained. These are filtered off and neutralized with one molecule of hydrochloric acid. The procaine hydrochloride obtained on evaporation crystallizes from ethanol in needles melting at 156° C. Novocaine is a white, odorless, crystalline powder, soluble in an equal weight of water.[2]
See Also
References
- ↑ Wikipedia: Procaine#Synthesis
- ↑ Organic medical chemicals, by M. Barrowliff, 107, 1921