631-61-8

Basic information

• Product Name: Ammonium acetate
• Synonyms: acetated’ammonium;Mindererus's spirit;AMMONIUM ACETATE TS;AMMONIUM ACETATE;ACETIC-AMMONIUM ACETATE;ACETIC ACID, AMMONIUM SALT;NH4OAC;WATER WITH AMMONIUM ACETATE
• CAS NO: 631-61-8
• Molecular Formula: C₂H₄O₂*H₃N
• Molecular Weight: 77.08
• EINECS: 211-162-9
• Product Categories: Pharmaceutical Intermediates;Inorganic Chemicals;ACS GradeSynthetic Reagents;Essential Chemicals;Routine Reagents;Buffers A to ZBiological Buffers;SigmaUltra Buffers;BioUltraProtein Structural Analysis;Molecular Biology;Ammonium Salts;AmmoniumMetal and Ceramic Science;Salts;Optimization Reagents;Protein Structural Analysis;X-Ray Crystallography;HPLC Buffer - SolidChromatography/CE Reagents;HPLC;HPLC Buffer;HPLC Buffers;Solid;Solvents, Buffers and Reagents for LuminescenceBiological Buffers;AlphabeticalBiochemicals and Reagents;Biological Buffers;BioUltra Buffers;Luminescent Compounds/Detection;Zwitterionic;Ammonium;AmmoniumMolecular Biology;BiochemicalsBiological Buffers;Buffers A to Z;Inorganic Salts;Molecular Biology Reagents;Synthetic Reagents;A-B, Puriss p.a. ACS;Analytical Reagents for General Use;Puriss p.a. ACS;A-B, Puriss p.a.;Puriss p.a.;A-B, Puriss p.a. ACSEssential Chemicals;ACS Grade;Buffer Convenience Packaging;Buffer SolutionsBio
• Mol File: 631-61-8.mol
• Article Data: 6

Chemical Properties

• Melting Point: 110-112 °C (dec.)(lit.)
• Boiling Point: 138.46°C (rough estimate)
• Flash Point: 136 °C
• Appearance: White/Solid
• Density: 1.07 g/mL at 20 °C
• Vapor Pressure: 13.9mmHg at 25°C
• Refractive Index: 1.4350 (estimate)
• Storage Temp.: 2-8°C
• Solubility: H2O: 1 M at 20 °C, clear, colorless
• PKA: 4.6(Acetic Acid), 9.3(Ammonium Hydroxide)(at 25℃)
• Water Solubility: 1480 g/L (20 ºC)
• Sensitive: Hygroscopic
• Stability: Hygroscopic
• Merck: 14,495
• BRN: 4186741
• CAS DataBase Reference: Ammonium acetate(CAS DataBase Reference)
• NIST Chemistry Reference: Ammonium acetate(631-61-8)
• EPA Substance Registry System: Ammonium acetate(631-61-8)

Safety Data

• Hazard Codes: F:Highly flammable
• Safety Statements: 24/25
• RIDADR: UN 9079
• WGK Germany: 3
• RTECS: AF3675000
• F: 3
• TSCA: Yes
• Hazardous Substances Data: 631-61-8(Hazardous Substances Data)

Usage

Chemical Description

Ammonium acetate is a salt composed of ammonium and acetate ions.

Chemical Description

Ammonium acetate is a salt that is commonly used as a reagent in organic synthesis.

Chemical Description

Ammonium acetate and glycine are used in the reductive amination step to prepare the auxiliaries.

InChI:InChI=1/C2H4O2.H3N/c1-2(3)4;/h1H3,(H,3,4);1H3

Synthetic route

Acetic acid (2R,4R)-2,4-dimethyl-3-nitro-5-oxo-oxazolidin-2-yl ester (130642-14-7, 130642-18-1) → acetamide (60-35-5) + ammonium acetate (631-61-8) + N-nitroalaninamide (130642-15-8) + Ammonium lactate (515-98-0) + rac-Ala-OH (302-72-7)

Conditions	Yield
With ammonia In diethyl ether at 25℃; for 0.5h; Mechanism;	A n/a B n/a C n/a D n/a E 60%

acetic anhydride (108-24-7) + Millon's base → mercury(II) diacetate (1600-27-7) + ammonium acetate (631-61-8) + acetic acid (64-19-7)

5-acetylamino-[1,2,4]dithiazole-3-thione (23405-40-5) + ammonia (7664-41-7) → ammonium acetate (631-61-8) + ammonium thiocyanate (1147550-11-5) + ammonium sulfide

Conditions	Yield
at 120℃; im Rohr;

acetamide (60-35-5) + water (7732-18-5) → ammonium acetate (631-61-8)

Conditions	Yield
at 170 - 195℃; Gleichgewicht;

acetamide (60-35-5) + concentrated potassium persulfate → ammonium acetate (631-61-8) + acetic acid (64-19-7)

methanol (67-56-1) + acetic acid methyl ester (79-20-9) + ammonia (7664-41-7) → acetamide (60-35-5) + ammonium acetate (631-61-8)

Conditions	Yield
at 25℃; Geschwindigkeit;

ethanol (64-17-5) + acetic acid methyl ester (79-20-9) + ammonia (7664-41-7) → acetamide (60-35-5) + ammonium acetate (631-61-8)

Conditions	Yield
at 25℃; Geschwindigkeit;

1-Propyl acetate (109-60-4) + aqueous alcoholic NH3 → acetamide (60-35-5) + ammonium acetate (631-61-8)

acetic acid methyl ester (79-20-9) + ammonia (7664-41-7) + aqueous dioxane → acetamide (60-35-5) + ammonium acetate (631-61-8)

Conditions	Yield
at 25℃; Geschwindigkeit;

diacetoxymethane (628-51-3) + ammonia (7664-41-7) → acetamide (60-35-5) + hexamethylenetetramine (100-97-0) + ammonium acetate (631-61-8)

Conditions	Yield
in der Kaelte;

N-nitroso-N,O-dimethylhydroxylamine (16339-12-1) + acetic acid (64-19-7) + platinum → methanol (67-56-1) + ammonium acetate (631-61-8) + methylamine acetate (6998-30-7)

Conditions	Yield
Hydrogenation;

2-diazo-acetophenone (3282-32-4) + acetic acid (64-19-7) + ethyl acetate (141-78-6) + palladium → ammonium acetate (631-61-8) + 2-Aminoacetophenone (613-89-8)

Conditions	Yield
Hydrogenation;

N-nitroso-O,N-diethyl hydroxylamine (56235-95-1) + acetic acid (64-19-7) + platinum → ethanol (64-17-5) + ammonium acetate (631-61-8) + ethylamine acetate

Conditions	Yield
Hydrogenation;

3-acetoxy-2-cyano-3-phenyl-acrylic acid methyl ester + ammonia (7664-41-7) → acetamide (60-35-5) + ammonium acetate (631-61-8) + ammonium compound of benzoylcyanoacetic acid methyl ester + β-imino-β-phenyl-α-cyano-propionic acid methyl ester

glutamic acid (amino acid) + acetic acid (64-19-7) → L-glutamic acid (56-86-0) + ammonium acetate (631-61-8)

Conditions	Yield
In water at 16 - 60℃; for 4.3h; Product distribution / selectivity;

diammonium succinate (2226-88-2) + acetic acid (64-19-7) → succinic acid (110-15-6) + ammonium acetate (631-61-8)

Conditions	Yield
In water at 15 - 140℃; under 50 - 760.051 Torr; for 0.0833333 - 25.33h; Product distribution / selectivity;
at 15 - 85℃; for 2 - 4.5h; Product distribution / selectivity;

diammonium succinate (2226-88-2) + acetic acid (64-19-7) → ammonium acetate (631-61-8) + monoammonium succinate (38457-08-8)

Conditions	Yield
Product distribution / selectivity;

diammonium adipate (3385-41-9, 5683-79-4, 19090-60-9) + acetic acid (64-19-7) → Adipic acid (124-04-9) + ammonium acetate (631-61-8)

Conditions	Yield
at 15 - 85℃; for 4.5h; Product distribution / selectivity;

octanedioic acid ; acidic ammonium salt (68838-35-7, 71411-67-1) + acetic acid (64-19-7) → octane-1,8-dioic acid (505-48-6) + ammonium acetate (631-61-8)

Conditions	Yield
at 15℃; for 18h; Product distribution / selectivity;

acetic acid (64-19-7) → ammonium acetate (631-61-8)

Conditions	Yield
With ammonia In water
With ammonium hydroxide at 40℃; Concentration; Temperature; Large scale;

2,3,4,5,6-pentahydroxy-hexanal (50-99-7, 59-23-4, 921-60-8, 1949-88-8, 1990-29-0, 2152-76-3, 2595-97-3, 2595-98-4, 3458-28-4, 4205-23-6, 5934-56-5, 5978-95-0, 5987-68-8, 6027-89-0, 6038-51-3, 7635-11-2, 10030-80-5, 15572-79-9, 19163-87-2, 23567-25-1, 26566-61-0, 30077-17-9, 31103-86-3, 39665-52-6, 40866-07-7, 58367-01-4, 58407-05-9, 58407-06-0, 83198-69-0, 83198-70-3, 83198-71-4, 93780-23-5, 145920-48-5) + DL-xylose (53106-52-8) → ethanol (64-17-5) + ammonium acetate (631-61-8) + L-lactic acid ; ammonium lactate (137296-15-2)

Conditions	Yield
With polypeptone; ammonia In water at 37℃; for 30h; pH=7; Product distribution / selectivity;

DL-xylose (53106-52-8) → ammonium acetate (631-61-8) + L-lactic acid ; ammonium lactate (137296-15-2)

Conditions	Yield
With polypeptone; ammonia In water at 37℃; for 25 - 30h; pH=7; Product distribution / selectivity;

ammonia (7664-41-7) + acetic acid (64-19-7) → ammonium acetate (631-61-8)

Conditions	Yield
for 0.0166667h;

1-[4-amino-3,5-dibromo-N-[(4-oxo-1-piperidinyl)carbonyl]-D-phenylalanyl]-4-(1-methyl-4-piperidinyl)-piperidine + ammonium acetate (631-61-8) → 1-[4-amino-N-[(4-amino-1-piperidinyl)carbonyl]-3,5-dibromo-D-phenylalanyl]-4-(1-methyl-4-piperidinyl)-piperidine

Conditions	Yield
Stage #1: 1-[4-amino-3,5-dibromo-N-[(4-oxo-1-piperidinyl)carbonyl]-D-phenylalanyl]-4-(1-methyl-4-piperidinyl)-piperidine; ammonium acetate With sodium cyanoborohydride In methanol at 20℃; Stage #2: In water	100%

ammonium acetate (631-61-8) + benzyl chloride (100-44-7) → Benzyl acetate (140-11-4)

Conditions	Yield
In glycerol at 80℃; for 1h; Solvent;	100%
In glycerol at 70℃; for 1h;	20%

1,3-dibutyl-5,6-dimethylbenzimidazolium iodide (1382354-48-4) + ammonium acetate (631-61-8) → C2H3O2(1-)*C17H27N2(1+) (1382354-56-4)

Conditions	Yield
Stage #1: ammonium acetate With Amberlyst A-26 (OH- form) In water at 20℃; Stage #2: 1,3-dibutyl-5,6-dimethylbenzimidazolium iodide In methanol	100%

ammonium acetate (631-61-8) + 1-butyl-4-methylpyridin-1-ium iodide (32353-64-3) → 1-butyl-4-methylpyridinium acetate (1289675-19-9)

Conditions	Yield
Stage #1: ammonium acetate With Amberlyst A-26 (OH- form) In water at 20℃; Stage #2: 1-butyl-4-methylpyridin-1-ium iodide In acetonitrile	100%

ammonium acetate (631-61-8) + 1,3-dimethylimidazolim iodide (4333-62-4) → 1,3-dimethyl-1H-imidazol-3-ium acetate (78643-53-5)

Conditions	Yield
Stage #1: ammonium acetate With Amberlyst A-26 (OH- form) In water at 20℃; Stage #2: 1,3-dimethylimidazolim iodide In methanol	100%

ammonium acetate (631-61-8) + 1-methyl-3-(n-butyl)imidazolium iodide (65039-05-6) → 3-butyl-1-methylimidazolium acetate (284049-75-8)

Conditions	Yield
Stage #1: ammonium acetate With Amberlyst A-26 (OH- form) In water at 20℃; Stage #2: 1-methyl-3-(n-butyl)imidazolium iodide In methanol	100%

ammonium acetate (631-61-8) + 1,3-bis(n-butyl)imidazolium iodide (143085-46-5) → 1,3-dibutylimidazolium acetate (723254-66-8)

Conditions	Yield
Stage #1: ammonium acetate With Amberlyst A-26 (OH- form) In water at 20℃; Stage #2: 1,3-dibutyl-1,3-imidazolium iodide In methanol	100%

3Mg(2+)*Al(3+)*8HO(1-)*0.5CO3(2-)*2H2O + ammonium acetate (631-61-8) → Mg3Al(OH)8(AcO)∙2H2O

Conditions	Yield
In methanol at 25℃; for 1h; Temperature; Time; Solvent; Sonication; Inert atmosphere;	100%

ammonium acetate (631-61-8) + 1-[(2R,3S,4R,5R)-3,4-dihydroxy-5-(hydroxymethyl)tetrahydrofur-2-yl]-1,4-dihydropyridine-3-carboxamide (19132-12-8) → nicotinamide riboside acetate salt

Conditions	Yield
In water at 20℃; for 1h;	100%

(2R,4R)-tert-butyl 2-methyl-4-(tosyloxy)pyrrolidine-1-carboxylate (859213-36-8) + ammonium acetate (631-61-8) → (2R,4S)-tert-butyl 4-acetoxy-2-methylpyrrolidine-1-carboxylate (874883-02-0)

Conditions	Yield
In toluene for 4h; Heating;	99%

1-(benzo[1,3]dioxol-5-yl)-2-(6-ethylpyridin-2-yl)ethane-1,2-dione (945244-60-0) + dimethoxyacetaldehyde (51673-84-8) + ammonium acetate (631-61-8) → 4-(benzo[1,3]dioxol-5-yl)-2-(dimethoxymethyl)-5-(6-ethylpyridin-2-yl)-1H-imidazole (945244-62-2)

Conditions	Yield
In methanol; water at 20℃; for 3h;	99%

ammonium acetate (631-61-8) + [5-Amino-1-(2-hydroxy-ethyl)-1H-imidazol-4-yl]-imino-acetonitrile (144486-49-7) → C2H4O2*C6H11N5O (1354414-08-6)

Conditions	Yield
In dimethyl sulfoxide at 40℃; for 18h;	99%

ammonium acetate (631-61-8) + 5-amino-1-(4'-methoxyphenyl)-4-(cyanoformimidoyl)imidazole (155579-28-5) → C2H4O2*C11H13N5O (1354414-06-4)

Conditions	Yield
In dimethyl sulfoxide at 40℃; for 18h;	99%

3-pyridinecarboxaldehyde (500-22-1) + 2-(1,3-benzodioxol-5-yl)ethyl isocyanide (65239-07-8) + ammonium acetate (631-61-8) → C18H19N3O4 (1357856-68-8)

Conditions	Yield
Stage #1: 3-pyridinecarboxaldehyde; ammonium acetate In trifluoroethanol at 60℃; for 0.5h; Ugi condensation; Stage #2: 2-(1,3-benzodioxol-5-yl)ethyl isocyanide In trifluoroethanol at 60℃; for 4h; Ugi condensation;	99%

ammonium acetate (631-61-8) + 4-amino-phenol (123-30-8) + 4-chlorobenzaldehyde (104-88-1) + benzil (134-81-6) → 4-(2-(4-chlorophenyl)-4,5-diphenyl-1H-imidazol-1-yl)phenol (1233762-71-4)

Conditions	Yield
With Fe-Cu/ZSM-5 In water at 20℃; for 0.0333333h; Sonication;	99%

ammonium acetate (631-61-8) + 4-methyl-benzaldehyde (104-87-0) + 3-chloro-aniline (108-42-9) + benzil (134-81-6) → 1-(3-chlorophenyl)-4,5-diphenyl-2-p-tolyl-1H-imidazole

Conditions	Yield
With Fe-Cu/ZSM-5 In water at 20℃; for 0.05h; Sonication;	99%

ammonium acetate (631-61-8) + 4-amino-phenol (123-30-8) + benzaldehyde (100-52-7) + benzil (134-81-6) → 4-(2,4,5-triphenyl-1H-imidazol-1-yl)phenol

Conditions	Yield
With Fe-Cu/ZSM-5 In water at 20℃; for 0.0333333h; Reagent/catalyst; Solvent; Time; Sonication;	99%

isatoic anhydride (118-48-9) + ammonium acetate (631-61-8) + 1-naphthaldehyde (66-77-3) → 2,3-dihydro-2-(naphthalene-1-yl)quinazolin-4(1H)-one (31785-60-1)

Conditions	Yield
With 3,3′-(butane-1,4-diyl)bis(1,2-dimethyl-1H-imidazole-3-ium) dibromide for 0.05h; Microwave irradiation;	99%

4-bromo-2,2,6,6-tetramethyl-3,5-heptanedione (39516-78-4) + ammonium acetate (631-61-8) → 1-[4-(1,1-dimethylethyl)-2-methyl-5-oxazolyl]-2,2-dimethyl-1-propanone (144837-00-3)

Conditions	Yield
In acetic acid for 27h; Heating;	98%

ammonium acetate (631-61-8) + 1-butyl-2,3-dimethylimidazolium bromide → 1-(1-butyl)-2,3-dimethylimidazolium acetate (945611-41-6)

Conditions	Yield
Stage #1: ammonium acetate With Amberlyst A-26 (OH- form) In water at 20℃; Stage #2: 1-butyl-2,3-dimethylimidazolium bromide In methanol	98%

isatoic anhydride (118-48-9) + ammonium acetate (631-61-8) + 4-chlorobenzaldehyde (104-88-1) → 2-(4-Chloro-phenyl)-2,3-dihydro-1H-quinazolin-4-one (13165-11-2)

Conditions	Yield
With 3,3′-(butane-1,4-diyl)bis(1,2-dimethyl-1H-imidazole-3-ium) dibromide for 0.0166667h; Microwave irradiation;	98%
With H3PO4/Al2O3 In neat (no solvent) at 100℃; for 0.2h;	95%

ammonium acetate (631-61-8) + 4-methyl-benzaldehyde (104-87-0) + 4-chloro-aniline (106-47-8) + benzil (134-81-6) → 1-(4-chlorophenyl)-2-(4-methylphenyl)-4,5-diphenyl-1H-imidazole (912952-59-1)

Conditions	Yield
With Fe-Cu/ZSM-5 In water at 20℃; for 0.0333333h; Sonication;	98%

ammonium acetate (631-61-8) + 4-methyl-benzaldehyde (104-87-0) + 2-hydroxy-2-phenylacetophenone (119-53-9) + 4-chloro-aniline (106-47-8) → 1-(4-chlorophenyl)-2-(4-methylphenyl)-4,5-diphenyl-1H-imidazole (912952-59-1)

Conditions	Yield
With Fe-Cu/ZSM-5 In water at 20℃; for 0.0333333h; Sonication;	98%

ammonium acetate (631-61-8) + 4-methyl-benzaldehyde (104-87-0) + benzil (134-81-6) + 4-fluoroaniline (371-40-4) → 1-(4-fluorophenyl)-4,5-diphenyl-2-p-tolyl-1H-imidazole

Conditions	Yield
With Fe-Cu/ZSM-5 In water at 20℃; for 0.05h; Sonication;	98%

ammonium acetate (631-61-8) + 4-methyl-benzaldehyde (104-87-0) + aniline (62-53-3) + benzil (134-81-6) → 2-(4-methylphenyl)-1,4,5-triphenyl-1H-imidazole (16112-37-1)

Conditions	Yield
With Fe-Cu/ZSM-5 In water at 20℃; for 0.0333333h; Sonication;	98%

ammonium acetate (631-61-8) + 4-methyl-benzaldehyde (104-87-0) + benzil (134-81-6) + 4-bromo-aniline (106-40-1) → 1-(4-bromophenyl)-2-(4-methylphenyl)-4,5-diphenyl-1H-imidazole (1332655-57-8)

Conditions	Yield
With Fe-Cu/ZSM-5 In water at 20℃; for 0.05h; Sonication;	98%

ammonium acetate (631-61-8) + benzaldehyde (100-52-7) + p-toluidine (106-49-0) + benzil (134-81-6) → 1-(4-methylphenyl)-2,4,5-triphenyl-1H-imidazole (16112-36-0)

Conditions	Yield
With Fe-Cu/ZSM-5 In water at 20℃; for 0.0333333h; Sonication;	98%

ammonium acetate (631-61-8) + 4-methyl-benzaldehyde (104-87-0) + acenaphthene quinone (82-86-0) → 8-(4-methylphenyl)-7H-acenaphtho[1,2-d]imidazole

Conditions	Yield
With Fe3O4 nanoparticles supported on graphene oxide loaded with C4H8SO3H In ethanol for 0.0833333h; Reflux; Green chemistry;	98%

isatoic anhydride (118-48-9) + ammonium acetate (631-61-8) + 4-bromo-benzaldehyde (1122-91-4) → 2,3-dihydro-2-(4-bromophenyl)quinazolin-4(1H)-one

Conditions	Yield
With 3,3′-(butane-1,4-diyl)bis(1,2-dimethyl-1H-imidazole-3-ium) dibromide for 0.0166667h; Microwave irradiation;	97%
With H3PO4/Al2O3 In neat (no solvent) at 100℃; for 0.283333h;	89%

isatoic anhydride (118-48-9) + ammonium acetate (631-61-8) + 3-nitro-benzaldehyde (99-61-6) → 2-(4-chlorophenyl)-2,3-dihydroquinazolin-4(1H)-one (26029-30-1)

Conditions	Yield
With 3,3′-(butane-1,4-diyl)bis(1,2-dimethyl-1H-imidazole-3-ium) dibromide for 0.0166667h; Microwave irradiation;	97%
With H3PO4/Al2O3 In neat (no solvent) at 100℃; for 0.15h;	90%

Upstream product

• 108-24-7 acetic anhydride 
• 23405-40-5 5-acetylamino-[1,2,4]dithiazole-3-thione 
• 7664-41-7 ammonia 
• 60-35-5 acetamide 
• 67-56-1 methanol 
• 79-20-9 acetic acid methyl ester 
• 64-17-5 ethanol 
• 109-60-4 1-Propyl acetate 
• 628-51-3 diacetoxymethane 
• 16339-12-1 N-nitroso-O,N-dimethylhydroxylamine 
• 64-19-7 acetic acid 
• 3282-32-4 2-diazo-acetophenone 
• 141-78-6 ethyl acetate 
• 56235-95-1 N-nitroso-O,N-diethyl hydroxylamine 

Downstream Products

• 42470-80-4 2-(4-chlorophenyl)pyridin-3-ol 
• 1193-62-0 methyl Pyrrole-2-carboxylate 
• 98593-60-3 3-amino-3-(5-methyl-[2]thienyl)-propionic acid 
• 856966-47-7 2-(3,4-dichloro-phenyl)-pyridin-3-ol 
• 642-98-8 D-ribonic acid 
• 626-55-1 3-Bromopyridine 
• 1120-90-7 3-iodopyridine 
• 717-79-3 3-amino-3-(3-fluoro-4-methoxy-phenyl)-propionic acid 
• 40953-16-0 triethyloxazole 
• 575-36-0 1-acetamidonaphthalene 
• 737-89-3 N,N-di(naphth-1-yl)amine 
• 134-32-7 1-amino-naphthalene 
• 971-85-7 triphenylmethyl acetate 
• 1947-47-3 3-amino-2-phenyl-1H-inden-1-one 

Relevant articles and documents

Method for preparing 3-amino-4,4,4-trifluorocrotonate

The invention discloses a method for preparing 3-amino-4,4,4-trifluorocrotonate with high raw material utilization rate. According to the invention, 4,4,4-trifluoroacetyl ethyl acetate and excessive ammonium acetate are subjected to an amination reaction to obtain a reaction solution, then the reaction solution is separated to an organic phase and an aqueous phase, ammoniacal liquor is added in the aqueous phase to obtain ammonium acetate, and finally ammonium acetate is cycled to continuous reaction.

PROCESS FOR PREPARING AMINO ACIDS USING THE AMIDOCARBONYLATION REACTION (1)

The present invention relates to a sequence for the preparation of amino acids, for example alpha amino acids, in particular methionine, by making use of an amidocarbonylation reaction and reuse of the catalyst.

PROCESS FOR PRODUCING LACTIDE AND PROCESS FOR PRODUCING POLYLACTIC ACID STARTING WITH FERMENTED LACTIC ACID

According to the present invention, a process for consistently producing lactide from ammonium lactate obtained by lactic fermentation, and a process for consistently producing polylactic acid from ammonium lactate obtained by lactic fermentation, are provided. A process for producing lactide, which comprises the steps of: (1) synthesizing lactate ester from ammonium lactate obtained by lactic fermentation; (2) polycondensing the lactate ester in the presence of a catalyst other than monobutyltin, whereby polylactic acid with a weight-average molecular weight of less than 15,000 (lactic acid prepolymer) is synthesized; and (3) depolymerizing the polylactic, whereby lactide is produced. A process for producing polylactic acid, which comprises the additional step of (4) ring-opening polymerizing said lactide, whereby polylactic acid is obtained. A process for producing lactate ester from ammonium lactate obtained by lactic fermentation.