Synthesis of benzoic acid

Preparation of benzoic acid

Preparation of benzoic acid by hydrolyzing benzonitrile

Preparation of benzoic acid by hydrolyzing benzonitrile

Preparation of benzoic acid by hydrolyzing benzonitrile

A mixture of 5 ml (or 5.1 g) of benzonitrile and 75 ml of 10% aqueous sodium hydroxide is boiled under a reflux condenser until oily drops of benzonitrile disappears. The condenser is then detached and boiled in the open flask for a few minutes in order to remove free ammonia. Then the solution is cooled and neutralized by adding concentrated hydrochloric until precipitation of benzoic acid is complete. The crystals of benzoic acid are collected by filtration, washed well with cold water and dried. Yield is about 5.8 g. Benzoic acid is purified by crystallization from hot water yielding product, which melts at 121° C.

Practical organic chemistry, by F. G. Mann, 192-193, 1960

Preparation of benzoic acid from benzyl chloride (benzyl alcohol)

5 g of benzyl chloride and 4 g of anhydrous sodium carbonate in 50 ml of water are mixed in a round flask attached to a reflux condenser, and boiled gently. A solution of 8-5 g of potassium permanganate in 150 ml of water is gradually dropped in from a dropping-funnel pushed through the top of the condenser. In the course of 2-3 hours the pink color of the permanganate will have vanished and been replaced by a mass of dark brown precipitate of manganese dioxide. When the liquid is cold, a stream of sulfur dioxide is passed in until the manganese dioxide is dissolved as manganese sulfate. The liquid is allowed to cool and the benzoic acid, which separates, is filtered, washed with a little cold water, and recrystallized from hot water yielding final product with melting point 121° C.

A class-book of organic chemistry, by J. B. Cohen, 295, 1918

Preparation of benzoic acid and benzyl alcohol from benzaldehyde

Preparation of benzoic acid and benzyl alcohol from benzaldehyde

Preparation of benzoic acid and benzyl alcohol from benzaldehyde

20 g of benzaldehyde are treated in a stoppered cylinder or a thick-walled vessel with a cold solution of 18 g of potassium hydroxide in 12 g of water, and mixed until a permanent emulsion is formed. The mixture is then allowed to stand over night. The vessel is closed by a cork, and not a glass stopper, since at times a glass stopper becomes so firmly fastened that it can be removed only with great difficulty. To the crystalline paste (potassium benzoate) separating out, water is added until a clear solution is obtained from which the benzyl alcohol is extracted by repeatedly shaking with ether. After the evaporation of the ether the residue is subjected to distillation; benzyl alcohol passes over at 206° C. Yield, about-8 g. The benzoic acid is precipitated from the alkaline solution on acidifying with hydrochloric acid and purified from hot water yielding final product with melting point 121° C.

The practical methods of organic chemistry, by L. Gattermann, 274-275, 1909

Preparation of benzoic acid via Grignard reaction

Preparation of benzoic acid via Grignard reaction

Preparation of benzoic acid via Grignard reaction

2.6 g of clean magnesium powder are dried in an air oven at 110° C for 20 minutes and placed in a dry flask fitted with a reflux. A mixture of 40 ml of dry ether and 20.4 g of dry iodobenzene, and a crystal of iodine are then added. The flask is dipped in hot water or heated on a water bath so that the ether boils gently. In about half an hour a white flocculet precipitate begins to form, and when the heat of the reaction makes the ether boil vigorously, the water bath is removed. The flask is now wrapped in a dry cloth to conserve the heat of the reaction, and in the course of 2 hours the magnesium is practically all dissolved. (If this does not occur, traces of moisture are probably present, and the experiment must be repeated, the ether being distilled off and again dried over sodium.) When the boiling of the ether slackens, the flask is reheated for half an hour as before on a water bath. The flask is then cooled in ice-water, the condenser removed, and a slow current of carbon dioxide, washed and dried as in the previous experiment, led into the ethereal solution, which may still contain traces of undissolved magnesium. The cooling must be continued throughout the operation. The reaction mixture forms wo layers, an upper layer of ether, and a heavy resinous lower layer of the reaction product. If the gas current is too rapid, only a slight layer of resinous mass will be obtained, but the preparation will still succeed if the cooling be thorough. Powdered ice is now added, and then, slowly, 30 ml 15% of hydrochloric acid. The precipitated benzoic acid is extracted with ordinary ether, the latter removed on a water bath, and the residue gently warmed with dilute caustic alkali. The undissolved portion is filtered off, and the benzoic acid reprecipitated with hydrochloric acid. More acid is obtained by extracting the mother liquor with ether. The whole is recrystallized from hot water. Yield 90%, colourless needles; soluble in hot water, and in alcohol and ether; volatile in steam; m.p. 122° C; b.p. 250° C.

Systematic organic chemistry, by W. M. Cumming, 119-120, 1937.


benzoic acid



InChI Key


Canonical SMILES


MeSH Synonyms

Acid, Benzoic, Benzoate, Potassium, Benzoic Acid, Kendall Brand of Benzoic Acid Sodium Salt, Potassium Benzoate, Ucephan

Depositor-Supplied Synonyms

benzoic acid, Dracylic acid, 65-85-0, Benzeneformic acid, benzenecarboxylic acid, phenylformic acid, Carboxybenzene, Phenylcarboxylic acid, Benzenemethanoic acid, Retardex, Benzoesaeure GK, Benzoesaeure GV, Retarder BA, Tenn-Plas, Acide benzoique, Salvo liquid, Solvo powder, Flowers of benzoin, Benzoesaeure, Flowers of benjamin, Benzoic acid, tech., Unisept BZA, HA 1 (acid), Diacylic acid, Oracylic acid, Benzoic acid (natural), Kyselina benzoova, HA 1, Benzenemethonic acid, Benzoate (VAN), Benzoesaeure [German], Caswell No. 081, NSC 149, Acide benzoique [French], Acido benzoico [Italian], Salvo, liquid, Solvo, powder, Kyselina benzoova [Czech], E 210, FEMA No. 2131, CCRIS 1893, HSDB 704, AI3-0310, E210, CHEBI:30746, AI3-03710, Aromatic carboxylic acid, UNII-8SKN0B0MIM, EPA Pesticide Chemical Code 009101, Benzoic acid [USAN:JAN], WPYMKLBDIGXBTP-UHFFFAOYSA-N, Benzeneformate, Phenylformate, EINECS 200-618-2, Tennplas, SBB040515, Benzenemethanoate, Benzenecarboxylate, Retarded BA, DSSTox_CID_143, Phenyl carboxylic acid, DSSTox_RID_75396, DSSTox_GSID_20143, Benzoic acid-ring-UL-14C, Benzoic acid, ammonium salt, CAS-65-85-0, NSC7918, 1079-02-3, Benzoic acid (TN), phenylcarboxy, Benzoicacid, Diacylate, Dracylate, Acido benzoico, Aromatic acid, Salvo powder, Retarder BAX, 1gyx, 1kqb, Benzoic acid, tech, Sodium benzoic acid, Benzoic acid / Benzoate, WLN: QVR, BENZOIC ACID, ACS, 8SKN0B0MIM, BENZOIC ACID- D5, Benzoic acid [USP:JAN], bmse000300, CHEMBL541, Epitope ID:139965, AC1L18SV, AC1Q73KP, SCHEMBL1378, ACMC-1BI02, Benzoic acid (JP16/USP), KSC352Q8R, MLS002415717, 47849_SUPELCO, ARONIS27062, B2670_SIGMA, BIDD:ER0597, W213101_ALDRICH, W213128_ALDRICH, 18102_RIEDEL, 33045_RIEDEL, 33047_RIEDEL, 427608_ALDRICH, C7H6O2, NSC149, ScavengePore™ benzoic acid, 12353_FLUKA, 33045_FLUKA, 73983_FLUKA, CTK2F2888, HMDB01870, Benzoic acid (7CI,8CI,9CI), NSC-149, MolPort-000-871-563, 18102_SIAL, 33047_SIAL, HMS2092F18, HMS2267D03, Pharmakon1600-01503001, 109479_SIAL, 242381_SIAL, 427608_SIAL, Tox21_202403, Tox21_300180, ANW-35104, ANW-44013, LS-280, NSC758203, STK301730, AKOS000119619, BS-3752, CCG-213088, DB03793, MCULE-4467353796, NE10192, NSC-758203, RL04514, RTR-032704, NCGC00091886-01, NCGC00091886-02, NCGC00091886-03, NCGC00254112-01, NCGC00259952-01, 4CN-0999, AJ-07949, AK109354, AN-22195, AN-23749, BP-30148, K073, KB-75310, SMR001252220, AB1002068, DB-029471, RT-004576, TR-035735, 606-EP2269610A2, 606-EP2269988A2, 606-EP2270002A1, 606-EP2270006A1, 606-EP2270008A1, 606-EP2270009A1, 606-EP2270010A1, 606-EP2270011A1, 606-EP2270114A1, 606-EP2272822A1, 606-EP2272827A1, 606-EP2272848A1, 606-EP2274983A1, 606-EP2275105A1, 606-EP2275401A1, 606-EP2275413A1, 606-EP2277507A1, 606-EP2277848A1, 606-EP2277867A2, 606-EP2277870A1, 606-EP2277879A1, 606-EP2277881A1, 606-EP2280003A2, 606-EP2280010A2, 606-EP2281559A1, 606-EP2281563A1, 606-EP2281812A1, 606-EP2281819A1, 606-EP2281823A2, 606-EP2284146A2, 606-EP2284147A2, 606-EP2284149A1, 606-EP2284160A1, 606-EP2284165A1, 606-EP2284169A1, 606-EP2284178A2, 606-EP2284179A2, 606-EP2286795A1, 606-EP2287153A1, 606-EP2287156A1, 606-EP2287161A1, 606-EP2287162A1, 606-EP2287165A2, 606-EP2287166A2, 606-EP2289510A1, 606-EP2289876A1, 606-EP2289883A1, 606-EP2289890A1, 606-EP2292592A1, 606-EP2292597A1, 606-EP2292617A1, 606-EP2292619A1, 606-EP2292620A2, 606-EP2292621A1, 606-EP2292624A1, 606-EP2295401A2, 606-EP2295402A2, 606-EP2295416A2, 606-EP2295418A1, 606-EP2295424A1, 606-EP2295426A1, 606-EP2295427A1, 606-EP2295429A1, 606-EP2295433A2, 606-EP2295438A1, 606-EP2295550A2, 606-EP2298734A2, 606-EP2298735A1, 606-EP2298742A1, 606-EP2298744A2, 606-EP2298748A2, 606-EP2298755A1, 606-EP2298758A1, 606-EP2298759A1, 606-EP2298772A1, 606-EP2298776A1, 606-EP2298783A1, 606-EP2301536A1, 606-EP2301538A1, 606-EP2301911A1, 606-EP2301924A1, 606-EP2301925A1, 606-EP2301929A1, 606-EP2301931A1, 606-EP2301935A1, 606-EP2301937A1, 606-EP2301939A1, 606-EP2301940A1, 606-EP2305250A1, 606-EP2305257A1, 606-EP2305646A1, 606-EP2305651A1, 606-EP2305659A1, 606-EP2305662A1, 606-EP2305664A1, 606-EP2305668A1, 606-EP2305669A1, 606-EP2305672A1, 606-EP2305674A1, 606-EP2305675A1, 606-EP2305679A1, 606-EP2305687A1, 606-EP2308833A2, 606-EP2308839A1, 606-EP2308848A1, 606-EP2308851A1, 606-EP2308854A1, 606-EP2308857A1, 606-EP2308858A1, 606-EP2308861A1, 606-EP2308865A1, 606-EP2308873A1, 606-EP2308875A1, 606-EP2308877A1, 606-EP2311455A1, 606-EP2311801A1, 606-EP2311802A1, 606-EP2311803A1, 606-EP2311807A1, 606-EP2311809A1, 606-EP2311810A1, 606-EP2311811A1, 606-EP2311815A1, 606-EP2311816A1, 606-EP2311817A1, 606-EP2311818A1, 606-EP2311831A1, 606-EP2311842A2, 606-EP2314295A1, 606-EP2314579A1, 606-EP2314584A1, 606-EP2314588A1, 606-EP2314593A1, 606-EP2316457A1, 606-EP2316458A1, 606-EP2316459A1, 606-EP2316825A1, 606-EP2316826A1, 606-EP2316827A1, 606-EP2316828A1, 606-EP2316836A1, 606-EP2371814A1, 606-EP2371831A1, 606-EP2372017A1, 606-EP2374788A1, 606-EP2377845A1, B0062, B2635, FT-0622705, ST24030107, ST45061539, C00180, C00539, D00038, A835250, 3B4-0034, I01-1943, 0BE368DC-6DE6-4927-AECF-E4BB2968A4A0, S4161,65-85-0, S4162,121-54-0, Mettler-Toledo(R) Calibration substance ME 18555, Benzoic acid, Benzoic acid,4-fluoro-2,6-dimethyl-, methyl ester, InChI=1/C7H6O2/c8-7(9)6-4-2-1-3-5-6/h1-5H,(H,8,9, 331473-08-6, 8013-63-6, BOX

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  1. Marcos Reinaldo

    Please, the cannizzaro reaction the products formed are benzoic acid and benzyl alcohol.
    Congratulations for wonderful work

  2. Fritz Haber

    More trivially, acidifying a solution of a benzoate salt, e.g sodium benzoate with hydrochloric acid will also yield benzoic acid in the form of a precipitate as it is hardly soluble in cold water.

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