May 28, 2021 | Heterocyclic Building Blocks-Benzoxazole

Analyzing the synthesis route of 4-Aminobenzo[d]oxazol-2(3H)-one

The chemical industry reduces the impact on the environment during synthesis,81900-93-8,4-Aminobenzo[d]oxazol-2(3H)-one,I believe this compound will play a more active role in future production and life.

81900-93-8, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 4-Aminobenzo[d]oxazol-2(3H)-one, cas is 81900-93-8,the benzoxazole compound, it is a common compound, a new synthetic route is introduced below.

Commercially available 2-chloro-4-trifluoromethylbenzylamine (572 mg, 2.7 mmol) was dissolved in 20ml of AcOEt and at 0C triphosgene (809 mg, 2.7 mmol) was added to the solution. The mixture was warmed at 80C for 4 hours then evaporated and dissolved in 5 ml of DMF. The solution of the isocyanate was added dropwise to a solution in DMF (5 ml) of compound lb (270 mg, 1.8 mmol) and the mixture was warmed at 80C for 8 hours. (TLC AcOEt). The solvent was evaporated and the crude was dissolved in AcOEt (30 ml) and washed with water (1 X 20 ml) and brine. The organic phase was dried over sodium sulfate and concentrated under vacuum. The purification of the crude residue by chromatographic column gave 70 mg of a white solid. Yield = 10% ‘HNMR (DMSO, 400 MHz) delta 4.45 (2H, d, J = 6 Hz), 6.97 (2H, d, J = 4.4 Hz), 7.07 (2H, m), 7.63 (1H, d, J = 8 Hz), 7.74 (2H, d), 7.86 (1H, s), 8.61 (1H, bs), 10.90 (1H, bs); [M+1] 386.6 (C16H11CIF3N3O3 requires 385.7).

Reference：
Patent; PHARMESTE S.R.L.; NAPOLETANO, Mauro; TREVISANI, Marcello; PAVANI, Maria Giovanna; FRUTTAROLO, Francesca; WO2011/120604; (2011); A1;,
Benzoxazole – Wikipedia
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Downstream synthetic route of 4-Aminobenzo[d]oxazol-2(3H)-one

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 4-Aminobenzo[d]oxazol-2(3H)-one, 81900-93-8

Example 32: 1-(4-(trifluoromethyl)-2-morpholinobenzyl)-3-(2,3-dihydro-2-oxobenzo[d]oxazol-4-yl)urea (scheme 1) Preparation of 1-(4-(trifluoromethyl)-2-morpholinobenzyl)-3-(2,3-dihydro-2-oxobenzo[d]oxazol-4-yl)urea Amine 2d (362 mg, 3.8 mmol) was dissolved in 20 ml of AcOEt and at 0C triphosgene (1.12 g, 1equiv.) was added to the solution. The mixture was warmed at 80C for 4 hours then evaporated and the residue was dissolved in 5 ml of DMF. The solution of the isocyanate was added dropwise to a solution in DMF (10 ml) of compound 1b (384 mg, 2.56 mmol) and the mixture was warmed at 80C for 8 hours. (TLC AcOEt). The solvent was evaporated and the crude was dissolved in AcOEt (30 ml) and washed with water (1 X 20 ml) and brine. The organic phase was dried over sodium sulfate and concentrated under vacuum. The purification of the crude residue by chromatographic column gave 200 mg of a pale rose solid. Yield = 18% 1HNMR (DMSO, 400 MHz) delta 2.91 (4H, m), 3.76 (4H, m), 4.46 (2H, d, J = 5.6 Hz), 6.97 (3H, m), 7.05 (1H, m), 7.36 (1H, s), 7.46 (1H, d), 7.54 (1H, d), 8.53 (1H, s), 11.00 (1H, bs); [M+1] 437.1 (C20H19F3N4O4 requires 436.4).).

Reference：
Patent; Pharmeste S.r.l.; EP2377850; (2011); A1;,
Benzoxazole – Wikipedia
Benzoxazole | C7H5NO – PubChem

Introduction of a new synthetic route about Benzo[d]oxazole-2-thiol

2382-96-9, In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles.,2382-96-9 ,Benzo[d]oxazole-2-thiol, other downstream synthetic routes, hurry up and to see

Benzo[d]oxazole-2-thiol, cas is 2382-96-9, it is a common heterocyclic compound, the benzoxazole compound, its synthesis route is as follows.

General procedure: To a solution of 1 mmol of thiol in acetonitrile (2mL), was added a solution of 8 mL of phosphate buffer including laccase (40 U) and 4-phenyl urazole (10 mol%). The resulting mixture was stirred under air at room temperature for the time specified. After completion of the reaction (monitored by TLC), NaOH (10%, 10 mL). The combined organic phases were dried over anhydrous Na2SO4, filtered and evaporated under reduced pressure. The crude products were purified by recrystallization or chromatography on silica gel (n-hexane/EtOAc, 5/1). All the products were known and characterized by comparison of their spectral data (1H NMR) and physical properties (melting point) with those of authentic samples.

Reference：
Article; Khaledian, Donya; Rostami, Amin; Zarei, Seyed Amir; Catalysis Communications; vol. 114; (2018); p. 75 – 78;,
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Extracurricular laboratory: Synthetic route of 2382-96-9

2382-96-9, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. Benzo[d]oxazole-2-thiol, cas is 2382-96-9,the benzoxazole compound, it is a common compound, a new synthetic route is introduced below.

Procedure for symmetrical molecules: DDQ (0.5 mmol) was added to an ice-cooled solution of thiol (1 mmol) in dichloromethane (3.0 mL). The reaction mixture stirred for 5 min at 0 C and monitored by TLC analysis. The reaction mixture was concentrated under reduced pressure and directly purified by column chromatography by gradient elution of ethyl acetate in hexanes to give the title compounds.

Reference：
Article; Vandavasi, Jaya Kishore; Hu, Wan-Ping; Chen, Chung-Yu; Wang, Jeh-Jeng; Tetrahedron; vol. 67; 46; (2011); p. 8895 – 8901;,
Benzoxazole – Wikipedia
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The important role of 59-49-4

59-49-4, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 2-Benzoxazolinone, cas is 59-49-4,the benzoxazole compound, it is a common compound, a new synthetic route is introduced below.

Sodium hydride (7.00 mmol) was added to a chilled (0 C.) solution of benzo[d]oxazol-2(3H)-one (4.81 mmol) in tetrahydrofuran (20 mL) and the reaction mixture was maintained for 30 min. Methyl iodide (7.25 mmol) was added dropwise and the reaction mixture was maintained for 6 h at rt. The reaction mixture was diluted with ethanol (10 mL) and the mixture was concentrated. The residue was diluted with water (50 mL) and was extracted with dichloromethane (3*20 mL). The combined organic layers were dried (sodium sulfate), filtered and concentrated to afford 3-methylbenzo[d]oxazol-2(3H)-one in 82% yield as a light red solid.

Reference：
Patent; Memory Pharmaceuticals Corporation; US2010/22581; (2010); A1;,
Benzoxazole – Wikipedia
Benzoxazole | C7H5NO – PubChem

The important role of 81900-93-8

Example 33: 1-(4-chlorobenzyl)-3-(2,3-dihydro-2-oxobenzo[d]oxazol-4-yl)urea (scheme 1) Preparation of 1-(4-chlorobenzyl)-3-(2,3-dihydro-2-oxobenzo[d]oxazol-4-yl)urea Commercially available p-chlorobenzylamine (1.6 g, 11.4 mmol) was dissolved in 60ml of AcOEt and at 0C triphosgene (3.38 g, 1equiv.) was added to the solution. The mixture was warmed at 80C for 4 hours then evaporated and the residue was dissolved in 30 ml of DMF. The solution of the isocyanate was added dropwise to a solution in DMF (10 ml) of compound 1b (1.7 g, 11.4 mmol) and the mixture was warmed at 80C for 8 hours. (TLC AcOEt 7 / petroleum ether 3). The solvent was evaporated and the crude was dissolved in AcOEt (80 ml) and washed with water (1 X 50 ml) and brine. The organic phase was dried over sodium sulfate and concentrated under vacuum. The purification of the crude residue by chromatographic column gave 500mg of a white solid. Yield = 14% 1HNMR (DMSO, 200 MHz) delta 4.57 (2H, d, J = 5.8 Hz), 6.53 (2H, m), 7.04 (1H, m), 7.41 (4H, s), 9.88 (1H, t), 11.53 (1H, s), 11.80 (1H, bs); [M+1] 318.5 (C15H12ClN3O3 requires 317.73).

Reference：
Patent; Pharmeste S.r.l.; EP2377850; (2011); A1;,
Benzoxazole – Wikipedia
Benzoxazole | C7H5NO – PubChem

Downstream synthetic route of Methyl benzo[d]oxazole-5-carboxylate

924869-17-0, In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles.,924869-17-0 ,Methyl benzo[d]oxazole-5-carboxylate, other downstream synthetic routes, hurry up and to see

As a common heterocyclic compound, it belongs to benzoxazole compound, name is Methyl benzo[d]oxazole-5-carboxylate, and cas is 924869-17-0, its synthesis route is as follows.

At 20 from Preparative Example 1The obtained methylbenzo [d] oxazole-5-carboxylate 354.1 mg (2.0 mmol) was dissolved in toluene (20 mL, 0.1 M)4-Bromophenol (380.6 mg, 2.2 mmol), Palladium acetate (Pd (OAc) 2, 4.5 mg, 1 mol%),Copper acetate monohydrate (Cu (OAc) 2 .H2O, 72.6 mg, 20 mol%),Tricyclohexylphosphine (PCy3, 280.4 mg, 50 mol%) And potassium carbonate (K2CO3, 552.8 mg, 4 mmol) were slowly added.The reaction mixture was reacted in a microwave at 160 C for 0.5 hour under a condition of 200W, The reaction was terminated by the addition of aqueous ammonium chloride solution, Ethyl acetate (10 mL) was extracted and extracted three times. After the water of the organic layer was removed with sodium sulfate,The solvent was concentrated with a vacuum distillation apparatus.The residue was purified by silica gel chromatography to give the title compoundMethyl 2- (4-hydroxyphenyl) benzo [d] oxazole-5-carboxylate(360.6 mg, 67%) was obtained

Reference：
Patent; Korea Institute of Science and Technology; Ham Jeong-yeop; Kim Tae-jeong; Park Yeong-tae; Kim Yeong-ju; Lee Jae-uk; Noh Tae-seop; Hwang Byeong-su; Kim Gyu-seon; (27 pag.)KR101792743; (2017); B1;,
Benzoxazole – Wikipedia
Benzoxazole | C7H5NO – PubChem

Analyzing the synthesis route of 5-Chlorobenzo[d]oxazole-2(3H)-thione

The chemical industry reduces the impact on the environment during synthesis,22876-19-3,5-Chlorobenzo[d]oxazole-2(3H)-thione,I believe this compound will play a more active role in future production and life.

22876-19-3, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 5-Chlorobenzo[d]oxazole-2(3H)-thione, cas is 22876-19-3,the benzoxazole compound, it is a common compound, a new synthetic route is introduced below.

To the suspension of 18′ (9.40 g, 50.64 mmol) in toluene (120 mL) was added cyclohexylamine (11.5 mL, 101 mmol) and refluxed for 48 h. The solvent was evaporated and residue was purified by silica gel column chromatography (gradient: hexanes to 30% ethyl acetate in hexanes) to afford 19′ (7.00 g, 74%) as a light orange solid. 1H NMR (400 MHz, CDCl3) delta 7.31 (s, IH), 7.13 (d, J = 12 Hz, IH), 6.99-6.97 (m, IH), 5.08 (bs, IH), 3.78-3.70 (m, IH), 2.14-2.1 1 (m, 2H), 1.81-1.76(m, 2H),1.65-1.57 (m, 2H), 1.49-1.31 (m, 2H), 1.29-1.28 (m, 2H); MS: ESI m/z 251 [M + H]+.

Reference：
Patent; RENOVIS, INC.; KAUB, Carl; GOWLUGARI, Sumithra; KINCAID, John; JOHNSON, Russell, James; O’MAHONY, Donogh, John Roger; ESTIARTE-MARTINEZ, Maria, de los Angeles; DUNCTON, Matthew; WO2010/39186; (2010); A2;,
Benzoxazole – Wikipedia
Benzoxazole | C7H5NO – PubChem

Extracurricular laboratory: Synthetic route of 4570-41-6

4570-41-6, In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles.,4570-41-6 ,Benzo[d]oxazol-2-amine, other downstream synthetic routes, hurry up and to see

Name is Benzo[d]oxazol-2-amine, as a common heterocyclic compound, it belongs to benzoxazole compound, and cas is 4570-41-6, its synthesis route is as follows.

General procedure: A mixture of (4-chloro-6-methylpyrimidin-2-yl)aminosulfonyl chloride (8) (1 mmol), benzoxazol-2-amine (2a)/benzothiazol-2-amine (2b)/1H-benzimidazol-2-amine (2c)/(benzoxazol-2-yl) methanamine (3a)/(benzothiazol-2-yl)methanamine (3b)/(1H-benzimidazol-2-yl)methanamine (3c), (2.2 mmol), dry ethanol (8 ml) and acatalytic amount of methanesulfonic acid (0.4 ml) wererefluxed for 3?5 h. The contents of the flask were cooledand diluted with water (25 ml). The separated solid wasfiltered, washed with water, dried and recrystallized from 2-propanol.

Reference：
Article; Seenaiah, Dandu; Rekha, Tamatam; Padmaja, Adivireddy; Padmavathi, Venkatapuram; Medicinal Chemistry Research; vol. 26; 2; (2017); p. 431 – 441;,
Benzoxazole – Wikipedia
Benzoxazole | C7H5NO – PubChem

New learning discoveries about 5676-60-8

5676-60-8, In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles.,5676-60-8 ,2-Methylbenzo[d]oxazol-6-amine, other downstream synthetic routes, hurry up and to see

Name is 2-Methylbenzo[d]oxazol-6-amine, as a common heterocyclic compound, it belongs to benzoxazole compound, and cas is 5676-60-8, its synthesis route is as follows.

General procedure: To a solution of compound 3 (3.37 mmol) in DMF (10 mL), charged respective compound V (a-p) (4.04 mmol) and heated to 80 C. After3 h, TLC analysis showed complete conversion of starting materials. The reaction mixture was cooled to room temperature, charged water (30 mL) and extracted with EtOAc (2 × 20 mL). The combined organic layer was washed with water (20 mL) followed by brine and concentrated under reduced pressure to obtain gummy liquid. This crude material was triturated with MTBE to afford desired product as solid and which used as such in next step without any further purification.

Reference：
Article; Balraju, Vadla; Jogula, Sridhar; Krishna, Vagolu Siva; Meda, Nikhila; Sriram, Dharmarajan; Bioorganic Chemistry; vol. 100; (2020);,
Benzoxazole – Wikipedia
Benzoxazole | C7H5NO – PubChem