2382-96-9

Usage

Uses

Used in Surface Treatment Industry:
2-Mercaptobenzoxazole is used as a corrosion inhibitor for the protection of metals from corrosion, enhancing the durability and longevity of metal surfaces.
Used in Medicinal Chemistry:
2-Mercaptobenzoxazole is used as an organic scaffold for the development of pharmaceutical compounds, due to its possession of several biological activities such as antibacterial, antifungal, anti-inflammatory, insecticidal, and herbicidal properties.
Used in Pharmaceutical Applications:
2-Mercaptobenzoxazole and its derivatives are employed in the development of drugs for various therapeutic applications, including analgesic, anti-HIV, antitubercular, anthelmintic, dye-stuffs, fluorescent, and as a photosensitizer. The incorporation of 4-oxothiazolidine and their 5-arylidene moieties in the 2-mercaptobenzoxazole framework has been found to enhance the activity of these compounds.

Preparation

2-Mercaptobenzoxazole has already been described in 1876 by Dunner (Ber. 9, (1876) page 465). 2-Mercaptobenzoxazole and its derivatives are prepared by processes which are based in principle on the reaction between o-aminophenol and alkali metal alkylxanthates. The alkali metal alkylxanthate here can either be employed as such, or it can be produced in the reaction mixture itself from an alkali, a lower alkanol and carbon disulphide.https://patents.google.com/patent/US4677209A/en

Reactions

2-Mercaptobenzoxazole with ethyl chloroacetate and anhydrous K2C03 in the presence of dry acetone was refluxed on water bath to give ethyl-2-(mercaptobenzoxazolo)acetate.

InChI:InChI=1/C7H5NOS/c10-7-8-5-3-1-2-4-6(5)9-7/h1-4H,(H,8,10)

Synthetic route

benzoxazole (273-53-0) → 2-sulfanyl-1,3-benzoxazole (2382-96-9)

Conditions	Yield
With 1.3-propanedithiol; potassium hydroxide In dimethyl sulfoxide at 130℃; for 12h; Inert atmosphere; Sealed tube;	92.6%
With 1.3-propanedithiol; dimethyl sulfoxide; potassium hydroxide at 130℃; for 12h; Inert atmosphere;	73%
With sulfur; 1,10-Phenanthroline; copper dichloride; sodium t-butanolate In N,N-dimethyl-formamide at 25℃; for 12h; Schlenk technique; Inert atmosphere;	67%

Thiram (137-26-8) + 2-amino-phenol (95-55-6) → 2-sulfanyl-1,3-benzoxazole (2382-96-9)

Conditions	Yield
In water at 80℃; Green chemistry;	92%
Stage #1: 2-amino-phenol With potassium carbonate In N,N-dimethyl-formamide for 0.0833333h; Stage #2: Thiram In N,N-dimethyl-formamide at 120℃; for 12h; Reagent/catalyst; Solvent; Temperature;	80%
In ethanol at 100℃; for 12h;	26%
In water at 80℃; for 3h;
In water at 80℃;

potassium ethyl xanthogenate (140-89-6) + 2-amino-phenol (95-55-6) → 2-sulfanyl-1,3-benzoxazole (2382-96-9)

Conditions	Yield
Stage #1: potassium ethyl xanthogenate; 2-amino-phenol In glycerol at 155℃; for 0.116667h; Microwave irradiation; Stage #2: With acetic acid In ethanol; water; glycerol pH=3 - 4;	91%
Stage #1: potassium ethyl xanthogenate; 2-amino-phenol In ethanol Reflux; Stage #2: With acetic acid In water pH=5;	52%
In ethanol Heating;
In ethanol; water Heating;
In ethanol

potassium isopropylxanthate (140-92-1) + 2-amino-phenol (95-55-6) → 2-sulfanyl-1,3-benzoxazole (2382-96-9)

Conditions	Yield
In N,N-dimethyl-formamide for 0.05h; Temperature; Time; Microwave irradiation;	90%

2-chloro-1,3-benzoxazole (615-18-9) → 2-hydroxybenzoxazole (59-49-4) + 2-sulfanyl-1,3-benzoxazole (2382-96-9)

Conditions	Yield
With sodium thiosulfate In ethanol; water Heating; Title compound not separated from byproducts;	A n/a B 86%

2-amino-phenol (95-55-6) + sodium dimethyldithiocarbamate (128-04-1) → 2-sulfanyl-1,3-benzoxazole (2382-96-9)

Conditions	Yield
With aluminum (III) chloride In water; N,N-dimethyl-formamide at 120℃; for 0.333333h; Temperature; Time;	83%

carbon disulfide (75-15-0) + 2-amino-phenol (95-55-6) → 2-sulfanyl-1,3-benzoxazole (2382-96-9)

Conditions	Yield
With potassium hydroxide In ethanol; water at 80℃; for 3h;	81%
With potassium hydroxide In ethanol; water for 3h; Heating;	78.2%
With potassium hydroxide In ethanol for 10h; Reflux;	77%

bis(2-benzoxazolyl) disulfide (36993-70-1) → 2-sulfanyl-1,3-benzoxazole (2382-96-9)

Conditions	Yield
With sodium citrate; titanium(III) chloride In ethanol; water; acetic acid pH 4.5 to 6.O;	76%

bis(2-benzoxazolyl) disulfide (36993-70-1) + (1'(R,S),3'-dihydroxy-2'(S,R)-ethylpropyl)benzene → 2-sulfanyl-1,3-benzoxazole (2382-96-9) + 2-(Benzooxazol-2-ylsulfanylmethyl)-1-phenyl-butan-1-ol

Conditions	Yield
With triphenylphosphine In tetrahydrofuran for 1h; Ambient temperature;	A n/a B 74%

bis(2-benzoxazolyl) disulfide (36993-70-1) + 2,2-Dibenzyl-butane-1,3-diol → 2-sulfanyl-1,3-benzoxazole (2382-96-9) + 2-(Benzooxazol-2-ylsulfanylmethyl)-2-benzyl-3-phenyl-propan-1-ol (200635-82-1)

Conditions	Yield
With triphenylphosphine In tetrahydrofuran rt., 1 h then reflux, 12 h;	A n/a B 72%

bis(2-benzoxazolyl) disulfide (36993-70-1) + (1S*,2R*)-2-Ethyl-1-phenylpropan-1,3-diol → 2-(butylthio)benzo[d]oxazole (22821-07-4) + 2-sulfanyl-1,3-benzoxazole (2382-96-9) + 2-(Benzooxazol-2-ylsulfanylmethyl)-1-phenyl-butan-1-ol

Conditions	Yield
With tributylphosphine In tetrahydrofuran for 1h; Ambient temperature;	A 10% B n/a C 65%

1.3-butanediol (18826-95-4, 107-88-0) + bis(2-benzoxazolyl) disulfide (36993-70-1) → 2-sulfanyl-1,3-benzoxazole (2382-96-9) + (±)-4-(1,3-benzoxazol-2-ylsulfanyl)butan-2-ol

Conditions	Yield
With triphenylphosphine In tetrahydrofuran for 1h; Ambient temperature;	A n/a B 58%

bis(2-benzoxazolyl) disulfide (36993-70-1) + syn-2-methyl-1-phenyl-1,3-propanediol (14366-91-7, 7087-77-6, 51451-31-1, 51451-32-2, 83909-75-5, 105497-76-5, 125760-89-6, 127379-92-4, 139068-60-3) → 2-(butylthio)benzo[d]oxazole (22821-07-4) + 2-sulfanyl-1,3-benzoxazole (2382-96-9) + 3-(Benzooxazol-2-ylsulfanyl)-2-methyl-1-phenyl-propan-1-ol

Conditions	Yield
With tributylphosphine In tetrahydrofuran for 1h; Ambient temperature;	A 5% B n/a C 54%

thiophosgene (463-71-8) + 2-amino-phenol (95-55-6) → 2-sulfanyl-1,3-benzoxazole (2382-96-9)

Conditions	Yield
In tetrahydrofuran at 0℃;	45%

1-phenyl-1,3-propanediol (4850-49-1) + bis(2-benzoxazolyl) disulfide (36993-70-1) → 2-(butylthio)benzo[d]oxazole (22821-07-4) + 2-sulfanyl-1,3-benzoxazole (2382-96-9) + 3-(Benzooxazol-2-ylsulfanyl)-1-phenyl-propan-1-ol

Conditions	Yield
With tributylphosphine In tetrahydrofuran for 1h; Ambient temperature;	A 4% B n/a C 38%

2-vinylthiobenzoxazole (22820-99-1) → acetaldehyde (75-07-0) + 2-sulfanyl-1,3-benzoxazole (2382-96-9)

Conditions	Yield
With hydrogenchloride; water In ethanol at 59.9℃; Kinetics; Rate constant; diff.temp. Eact diff.conc.of HCl;

potassium ethyldithiocarbamate (63467-57-2) + 2-amino-phenol (95-55-6) → 2-sulfanyl-1,3-benzoxazole (2382-96-9)

Conditions	Yield
Microwave irradiation;

carbon disulfide (75-15-0) + 2-amino-phenol (95-55-6) + Cyclopropylamine (765-30-0) → 2-sulfanyl-1,3-benzoxazole (2382-96-9)

Conditions	Yield
Stage #1: carbon disulfide; Cyclopropylamine In neat (no solvent) for 1h; Stage #2: 2-amino-phenol at 110℃; for 3h;

2-sulfanyl-1,3-benzoxazole (2382-96-9) + (1-decynyl)-[4-(trifluoromethyl)phenyl]-(tetrafluoroborato)-λ3-bromane → 1-decynyl 2-benzoxazolyl sulfide

Conditions	Yield
In dichloromethane at 0℃; for 1h;	100%

tetra(n-butyl)ammonium hydroxide (2052-49-5) + 2-sulfanyl-1,3-benzoxazole (2382-96-9) → tetra(n-butyl)ammonium benzoxazole-2-thiolate (75593-47-4)

Conditions	Yield
In methanol Inert atmosphere;	100%

2-sulfanyl-1,3-benzoxazole (2382-96-9) + 1-[(triisopropylsilyl)ethynyl]-1,2-benziodoxol-3(1H)-one → 2-(((triisopropylsilyl)ethynyl)thio)benzo[d]oxazole (1443746-62-0)

Conditions	Yield
Stage #1: 2-sulfanyl-1,3-benzoxazole With N,N,N',N'-tetramethylguanidine In tetrahydrofuran at 20℃; for 0.0833333h; Stage #2: 1-[(triisopropylsilyl)ethynyl]-1,2-benziodoxol-3(1H)-one In tetrahydrofuran at 20℃; for 0.0833333h; chemoselective reaction;	100%

2-sulfanyl-1,3-benzoxazole (2382-96-9) → bis(2-benzoxazolyl) disulfide (36993-70-1)

Conditions	Yield
With dihydrogen peroxide In water; ethyl acetate at 20℃; for 0.666667h; Green chemistry;	99%
With dihydrogen peroxide In ethyl acetate at 20℃; for 0.416667h; Solvent; Time;	98%
With dihydrogen peroxide at 20℃; for 0.166667h; Reagent/catalyst;	98%

2-sulfanyl-1,3-benzoxazole (2382-96-9) + C18H26FIO2*BF3 → 1-(2-benzoxazolylthio)-2-decanone

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

2-sulfanyl-1,3-benzoxazole (2382-96-9) + 4-(α-halogenophenylacetylamino)-1,5-dimethyl-2-phenyl-2,3-dihydro-1H-pyrazol-3-one → 2-(benzooxazol-2-ylsulfanyl)-N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)-2-phenyl-acetamide

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

para-bromophenacyl bromide (99-73-0) + 2-sulfanyl-1,3-benzoxazole (2382-96-9) → 2-(benzo[d]oxazol-2-ylthio)-1-(4-bromophenyl)ethanone (13944-97-3)

Conditions	Yield
With zinc(II) oxide In neat (no solvent) at 25 - 30℃;	97%
Stage #1: 2-sulfanyl-1,3-benzoxazole With sodium carbonate In ethanol; water at 20℃; Stage #2: para-bromophenacyl bromide In ethanol; water at 20℃;	95%
(i) NaOMe, (ii) /BRN= 607604/; Multistep reaction;

benzoyl chloride (98-88-4) + 2-sulfanyl-1,3-benzoxazole (2382-96-9) → S-(benzoxazol-2-yl) thiobenzolate (17688-44-7)

Conditions	Yield
With potassium carbonate; 1-butyl-3-methylimidazolium Tetrafluoroborate at 50℃; for 2h;	97%
With triethylamine In tetrahydrofuran at -20℃; for 0.333333h;	90%
With triethylamine In tetrahydrofuran at 60℃; for 12h; Reagent/catalyst; Solvent; Temperature;	75%
With pyridine In tetrahydrofuran at 20℃; for 0.0833333h; Sonication;

1-Chloro-4-(chloromethyl)benzene (104-83-6) + 2-sulfanyl-1,3-benzoxazole (2382-96-9) → 2-(4-chlorobenzylsulfanyl)benzoxazole (101094-63-7) + bis(2-benzoxazolyl) disulfide (36993-70-1)

Conditions	Yield
With tetraethylammonium bromide In acetonitrile Ambient temperature; electrooxidation;	A 97% B n/a

chloroacetic acid ethyl ester (105-39-5) + 2-sulfanyl-1,3-benzoxazole (2382-96-9) → benzoxazol-2'-yl-mercaptoacetic acid ethyl ester (73824-25-6)

Conditions	Yield
In acetonitrile Ambient temperature; electrooxidation, supporting electrolyte Et4NBr;	97%
With tetraethylammonium bromide In acetonitrile electrolysis, Pt-cathode;	97%
With potassium carbonate; 3-butyl-1-methyl-1H-imidazol-3-ium hexafluorophosphate at 50℃; for 2h;	93%

2-sulfanyl-1,3-benzoxazole (2382-96-9) + 4,4'-Dimethoxybenzhydrol (728-87-0) → 2-(bis(4-methoxyphenyl)methylthio)benzo[d]oxazole (1384458-40-5)

Conditions	Yield
With N-cetyl-N-(4-sulfobutyl)pyrrolidinium trifluoromethanesulfonate In 1,2-dichloro-ethane at 20℃; for 2h; Schlenk technique;	97%
In benzene for 0.5h; Acidic conditions;

N-(benzenesulfonyl)-N-[(trifluoromethyl)sulfanyl]benzenesulfonamide + 2-sulfanyl-1,3-benzoxazole (2382-96-9) → 2-((trifluoromethyl)sulfinothioyl)benzo[d]oxazole

Conditions	Yield
In dichloromethane at 20℃; for 12h; Schlenk technique;	97%

Upstream product

• 1520-26-9 2-hydroxyphenylthiourea 
• 615-18-9 2-chloro-1,3-benzoxazole 
• 64-17-5 ethanol 
• 140-89-6 potassium ethyl xanthogenate 
• 51-19-4 2-aminophenol hydrochloride 
• 86971-24-6 2-(benzylthio)benzo[d]oxazole 
• 17073-22-2 N-allyl-N'-(2-hydroxy-phenyl)-thiourea 
• 17356-08-0 thiourea 
• 95-55-6 2-amino-phenol 
• 75-15-0 carbon disulfide 
• 463-71-8 thiophosgene 
• 110-89-4 piperidine 
• 70989-48-9 2-thioxo-benzooxazole-3-carboximidic acid p-tolyl ester 
• 288-32-4 1H-imidazole 

Downstream Products

• 13673-62-6 2-methylsulfanyl-benzoxazole 
• 62652-30-6 2-(ethylthio)benzo[d]oxazol 
• 58089-32-0 2-(benzo[d]oxazol-2-ylthio)acetic acid 
• 833-50-1 2-phenylbenzo[d]oxazole 
• 6296-59-9 2-(benzamido)phenyl benzoate 
• 33388-23-7 3-benzoyl-2(3H)-benzoxazolethione 
• 92148-95-3 N-(4-methoxyphenyl)-1,3-benzoxazol-2-amine 
• 6631-42-1 N-phenyl-1,3-benzoxazol-2-amine 
• 39208-61-2 N-(3-methylphenyl)-1,3-benzoxazol-2-amine 
• 136540-09-5 2-N-methyl-N-phenylaminobenzoxazole 
• 615-18-9 2-chloro-1,3-benzoxazole 
• 68005-30-1 2-bromo-1,3-benzoxazole 
• 59-49-4 2-Benzoxazolinone 
• 24316-84-5 6-Brombenzoxazolinthion 

Relevant academic research and scientific papers

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