32863-32-4

Basic information

• Product Name: 4-Benzofurazancarboxaldehyde
• Synonyms: 2,1,3-Benzoxadiazole-4-carboxaldehyde (9CI);2,1,3-BENZOXADIAZOLE-4-CARBOXALDEHYDE;2,1,3-Benzoxadiazole-4-carbaldehyde;4-Benzofurazone Carboxaldehyde;2,1,3-Benzoxadiazole-4-aldehyde;Benzofurazon-4-Carboxaldehyde;4-FORMYL-BENZO[C][1,2,5]OXADIAZOLE;4-Benzofurazancarboxaldehyde ,97%
• CAS NO: 32863-32-4
• Molecular Formula: C₇H₄N₂O₂
• Molecular Weight: 148.12
• EINECS: 1592732-453-0
• Product Categories: ALDEHYDE;Aromatics;Heterocycles;Intermediates & Fine Chemicals;Pharmaceuticals
• Mol File: 32863-32-4.mol
• Article Data: 7

Chemical Properties

• Melting Point: 100-102°C
• Boiling Point: 277 °C
• Flash Point: 121 °C
• Appearance: /
• Density: 1.417
• Vapor Pressure: 0.005mmHg at 25°C
• Refractive Index: 1.677
• Storage Temp.: Refrigerator
• Solubility: Dichloromethane (Slightly), Chloroform (Slightly), Methanol (Slightly), Tetrahyd
• PKA: -1.86±0.45(Predicted)
• CAS DataBase Reference: 4-Benzofurazancarboxaldehyde(CAS DataBase Reference)
• NIST Chemistry Reference: 4-Benzofurazancarboxaldehyde(32863-32-4)
• EPA Substance Registry System: 4-Benzofurazancarboxaldehyde(32863-32-4)

Safety Data

• Statements: 36/37/38
• Safety Statements: 26-36/37/39
• HazardClass: IRRITANT
• Hazardous Substances Data: 32863-32-4(Hazardous Substances Data)

Usage

Chemical Properties

Light Brown Solid

Uses

A synthetic intermediate for the production of Isradipine.

InChI:InChI=1/C7H4N2O2/c10-4-5-2-1-3-6-7(5)9-11-8-6/h1-4H

Synthetic route

4-hydroxymethylbenzofurazan (175609-19-5) → benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4)

Conditions	Yield
With fluorosulfonyl fluoride; potassium carbonate; dimethyl sulfoxide at 20℃; for 12h; chemoselective reaction;	99%
With manganese(IV) oxide In chloroform for 2h; Ambient temperature;	92%
With pyridinium chlorochromate In dichloromethane at 0 - 30℃; for 2h;
With fluorosulfonyl fluoride; potassium carbonate; dimethyl sulfoxide at 20℃;

4-methyl-benzo[1,2,5]oxadiazole (29091-40-5) → benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4)

Conditions	Yield
With selenium(IV) oxide at 160℃; for 8h;	82%

4-(bromomethyl)benzo[c][1,2,5]oxadiazole (32863-30-2) → benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4)

Conditions	Yield
With sodium hydrogencarbonate In dimethyl sulfoxide at 100 - 150℃; Inert atmosphere;	71.6%
Multi-step reaction with 2 steps 1: 77 percent / calcium carbonate, water / dioxane / 3 h / Heating 2: 92 percent / manganese dioxide / CHCl3 / 2 h / Ambient temperature View Scheme

benzofurazan (273-09-6) + N,N-dimethyl-formamide (68-12-2, 33513-42-7) → benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4)

Conditions	Yield
With lithium diisopropyl amide In tetrahydrofuran at -78℃;	59%

4-methylbenzimidazole (4887-83-6) → benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4)

Conditions	Yield
Multi-step reaction with 2 steps 1: tetrachloromethane; N-Bromosuccinimide; dibenzoyl peroxide / 80 - 85 °C 2: sodium hydrogencarbonate / dimethyl sulfoxide / 100 - 150 °C / Inert atmosphere View Scheme

2-cyanoethylacetoacetate (65193-87-5) + methyl 3-aminocrotonate (21731-17-9) + benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → C19H18N4O5

Conditions	Yield
In isopropyl alcohol Inert atmosphere; Reflux;	97%

2-chloroethyl acetoacetate (54527-68-3) + benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → 2-[1-Benzo[1,2,5]oxadiazol-4-yl-meth-(E)-ylidene]-3-oxo-butyric acid 2-chloro-ethyl ester (210579-35-4)

Conditions	Yield
With hydrogenchloride In chloroform for 168h; Ambient temperature;	95%

4-amino-6-bromo-1H-indazole (885518-50-3) + benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → N-(benzo[c][1,2,5]oxadiazol-4-ylmethyl)-6-bromo-1H-indazol-4-amine

Conditions	Yield
With diethyl 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate; trifluoroacetic acid In methanol; dichloromethane at 45℃; for 4h;	92%

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → 4-hydroxymethylbenzofurazan (175609-19-5)

Conditions	Yield
With sodium tetrahydroborate In methanol at 0℃;	82%

ethyl acetoacetate (141-97-9) + benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → darodipine (72803-02-2)

Conditions	Yield
With ammonium carbonate at 70℃;	79.5%
With ammonium hydroxide In ethanol at 120℃; for 0.166667h; Hantzsch Dihydropyridine Synthesis; Flow reactor;	76%

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) + methyl 3-aminocrotonate (14205-39-1) → dimethyl 1,4-dihydro-2,6-dimethyl-4-(4-benzofurazanyl)-3,5-pyridinedicarboxylate

Conditions	Yield
With trifluoroacetic acid In ethanol at 0℃; for 1.5h;	70%

4-chloro-aniline (106-47-8) + benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → C13H10ClN3O (1454663-39-8)

Conditions	Yield
With sodium cyanoborohydride; acetic acid In methanol at 0℃;	67%

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → benzofurazan-4-carboxylic acid (32863-21-1)

Conditions	Yield
With sodium hydroxide In tetrahydrofuran at 25℃; for 10h; Reagent/catalyst; Temperature; Solvent;	57%

2-(4-diphenylmethyl-1-piperazinyl)ethyl acetoacetate (89226-49-3) + benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) + methyl 3-aminocrotonate (14205-39-1) → 4-Benzo[1,2,5]oxadiazol-4-yl-2,6-dimethyl-1,4-dihydro-pyridine-3,5-dicarboxylic acid 3-[2-(4-benzhydryl-piperazin-1-yl)-ethyl] ester 5-methyl ester; hydrochloride (90096-10-9)

Conditions	Yield
In isopropyl alcohol Heating;	45%

1-nitro-2-propanone (10230-68-9) + methyl 3-aminocrotonate (21731-17-9) + benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → 4-benzo[1,2,5]oxadiazol-4-yl-2,6-dimethyl-5-nitro-1,4-dihydro-pyridine-3-carboxylic acid methyl ester (105567-84-8)

Conditions	Yield
In isopropyl alcohol for 5h; Heating;	40%

2-chloro-5-aminoethylpyridine (54127-64-9) + benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → N-(benzo[c][1,2,5]oxadiazol-4-ylmethyl)-2-(6-chloropyridin-3-yl)ethylamine

Conditions	Yield
With sodium tetrahydroborate In methanol for 3h; Cooling with ice; Reflux;	30.21%

1-nitro-2-propanone (10230-68-9) + benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) + (1S,2R)-2-(3,5-dinitrophenylcarbonylamino)-2-methoxycarbonyl-1-methylethyl 3-aminocrotonate (250330-30-4) → (1S,2R)-2-(3,5-dinitrophenylcarbamoyl)-2-(methoxycarbonyl)ethyl 1,4-dihydro-2,6-dimethyl-3-nitro-4-(2,1,3-benzoxadiazol-4-yl)pyridine-5-carboxylate (651007-66-8) + (1S,2R)-2-(3,5-dinitrophenylcarbamoyl)-2-(methoxycarbonyl)ethyl 1,4-dihydro-2,6-dimethyl-3-nitro-4-(2,1,3-benzoxadiazol-4-yl)pyridine-5-carboxylate (651007-65-7)

Conditions	Yield
In ethanol at 25 - 80℃; for 18h;	A 27% B 20%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 2-(4-diphenylmethyl-1-piperazinyl)ethyl acetoacetate (89226-49-3) + benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → 5-Benzo[1,2,5]oxadiazol-4-yl-1,3,7-trimethyl-2,4-dioxo-1,2,3,4,5,8-hexahydro-pyrido[2,3-d]pyrimidine-6-carboxylic acid 2-(4-benzhydryl-piperazin-1-yl)-ethyl ester (97056-86-5)

Conditions	Yield
In isopropyl alcohol Heating;	13.5%

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) + 2-acetonyl-5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinane (111011-80-4) → (Z)-4-Benzo[1,2,5]oxadiazol-4-yl-3-(5,5-dimethyl-2-oxo-2λ5-[1,3,2]dioxaphosphinan-2-yl)-but-3-en-2-one (146139-64-2)

Conditions	Yield
With piperidine; trifluoroacetic acid In toluene for 8h; Heating;	12%

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) + 2-acetonyl-1-oxo-1,3,2-dioxaphosphorinane (115579-08-3) → (E)-4-Benzo[1,2,5]oxadiazol-4-yl-3-(2-oxo-2λ5-[1,3,2]dioxaphosphinan-2-yl)-but-3-en-2-one (115578-84-2)

Conditions	Yield
piperdinium acetate In benzene Heating;	8%

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) + diallyl acetonylphosphonate (112057-34-8) → {1-[1-Benzo[1,2,5]oxadiazol-4-yl-meth-(Z)-ylidene]-2-oxo-propyl}-phosphonic acid diallyl ester (112057-49-5, 112057-62-2)

Conditions	Yield
piperdinium acetate In isopropyl alcohol Heating;

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → (-)-(R)-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2,1,3-benzoxadiazol-4-yl)pyridine-5-carboxylic acid (98759-59-2)

Conditions	Yield
Multi-step reaction with 2 steps 1: 27 percent / ethanol / 18 h / 25 - 80 °C 2: 50 percent / 1,8-diazabicyclo[5.4.0]undec-7-ene / methanol / 24 h / 25 °C View Scheme

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → (+)-(S)-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2,1,3-benzoxadiazol-4-yl)pyridine-5-carboxylic acid (98759-58-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: 20 percent / ethanol / 18 h / 25 - 80 °C 2: 50 percent / 1,8-diazabicyclo[5.4.0]undec-7-ene / methanol / 24 h / 25 °C View Scheme

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → (-)-PN 202-791

Conditions	Yield
Multi-step reaction with 3 steps 1: 27 percent / ethanol / 18 h / 25 - 80 °C 2: 50 percent / 1,8-diazabicyclo[5.4.0]undec-7-ene / methanol / 24 h / 25 °C 3: 89 percent / K2CO3 / dimethylformamide / 24 h / 25 °C View Scheme

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → (+)-PN 202-791

Conditions	Yield
Multi-step reaction with 3 steps 1: 20 percent / ethanol / 18 h / 25 - 80 °C 2: 50 percent / 1,8-diazabicyclo[5.4.0]undec-7-ene / methanol / 24 h / 25 °C 3: 88.8 percent / K2CO3 / dimethylformamide / 24 h / 25 °C View Scheme

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → (-)-(R)-2-nitrooxyethyl 1,4-dihydro-2,6-dimethyl-3-nitro-4-(2,1,3-benzoxadiazol-4-yl)pyridine-5-carboxylate

Conditions	Yield
Multi-step reaction with 3 steps 1: 27 percent / ethanol / 18 h / 25 - 80 °C 2: 50 percent / 1,8-diazabicyclo[5.4.0]undec-7-ene / methanol / 24 h / 25 °C 3: 91 percent / K2CO3 / dimethylformamide / 24 h / 25 °C View Scheme

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → (+)-(S)-2-nitrooxyethyl 1,4-dihydro-2,6-dimethyl-3-nitro-4-(2,1,3-benzoxadiazol-4-yl)pyridine-5-carboxylate

Conditions	Yield
Multi-step reaction with 3 steps 1: 20 percent / ethanol / 18 h / 25 - 80 °C 2: 50 percent / 1,8-diazabicyclo[5.4.0]undec-7-ene / methanol / 24 h / 25 °C 3: 91 percent / K2CO3 / dimethylformamide / 24 h / 25 °C View Scheme

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → (-)-(R,R)-1-methyl-2-nitrooxyethyl 1,4-dihydro-2,6-dimethyl-3-nitro-4-(2,1,3-benzoxadiazol-4-yl)pyridine-5-carboxylate

Conditions	Yield
Multi-step reaction with 3 steps 1: 27 percent / ethanol / 18 h / 25 - 80 °C 2: 50 percent / 1,8-diazabicyclo[5.4.0]undec-7-ene / methanol / 24 h / 25 °C 3: 30 percent / K2CO3 / dimethylformamide / 168 h / 25 °C View Scheme

benzo[c][1,2,5]oxadiazole-4-carbaldehyde (32863-32-4) → (+)-(R,S)-1-methyl-2-nitrooxyethyl 1,4-dihydro-2,6-dimethyl-3-nitro-4-(2,1,3-benzoxadiazol-4-yl)pyridine-5-carboxylate

Conditions	Yield
Multi-step reaction with 3 steps 1: 27 percent / ethanol / 18 h / 25 - 80 °C 2: 50 percent / 1,8-diazabicyclo[5.4.0]undec-7-ene / methanol / 24 h / 25 °C 3: 30 percent / K2CO3 / dimethylformamide / 168 h / 25 °C View Scheme

Upstream product

• 4887-83-6 4-methylbenzimidazole 
• 273-09-6 benzofurazan 
• 68-12-2 N,N-dimethyl-formamide 
• 32863-30-2 4-(bromomethyl)benzo[c][1,2,5]oxadiazole 
• 29091-40-5 4-methyl-benzo[1,2,5]oxadiazole 
• 175609-19-5 4-hydroxymethylbenzofurazan 

Downstream Products

• 1454663-39-8 C₁₃H₁₀ClN₃O 
• 175609-19-5 4-hydroxymethylbenzofurazan 
• 1454663-40-1 C₁₅H₁₂ClN₃O₂ 
• 1454663-42-3 C₁₅H₁₁ClN₄O₄ 
• 1454663-41-2 C₁₅H₁₁ClN₄O₄ 
• 1454663-37-6 C₁₃H₇ClN₄O₄ 
• 1454663-44-5 C₁₃H₉ClN₄O₃ 
• 1454663-43-4 C₁₃H₉ClN₄O₃ 
• 32863-21-1 benzofurazan-4-carboxylic acid 
• 72803-02-2 darodipine 
• 154026-73-0 methyl 4-(2,1,3-benzoxadiazol-4-yl)-2,6-dimethyl-1-(2-nitrobenzyl)-1,4-dihydropyridine-3,5-dicarboxylate 
• 104785-90-2 2-acetyl-3-benzofurazan-4-yl-acrylic acid methyl ester 
• 104246-11-9 4-Benzo[1,2,5]oxadiazol-4-yl-5-(bis-allyloxy-phosphoryl)-2,6-dimethyl-1,4-dihydro-pyridine-3-carboxylic acid 2-(benzyl-methyl-amino)-ethyl ester 
• 651007-66-8 (1S,2R)-2-(3,5-dinitrophenylcarbamoyl)-2-(methoxycarbonyl)ethyl 1,4-dihydro-2,6-dimethyl-3-nitro-4-(2,1,3-benzoxadiazol-4-yl)pyridine-5-carboxylate 

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