852-38-0

Usage

Chemical Properties

white fine crystalline powder

Purification Methods

PBD is recrystallised from toluene. It is a good scintillation material [Brown et al. Discussion Faraday Soc 27 43 1959]. [Beilstein 27 III/IV 7283.]

InChI:InChI=1/C20H14N2O/c1-3-7-15(8-4-1)16-11-13-18(14-12-16)20-22-21-19(23-20)17-9-5-2-6-10-17/h1-14H

Synthetic route

benzoic acid hydrazide (613-94-5) + biphenyl-4-carboxylic acid (92-92-2) → 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0)

Conditions	Yield
With PS-PPh3; trichloroacetonitrile In acetonitrile at 150℃; for 0.333333h; microwave irradiation;	85%

C20H16N2O (412956-37-7) → 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0)

Conditions	Yield
Stage #1: C20H16N2O With iodine; potassium carbonate In dimethyl sulfoxide at 20℃; Green chemistry; Stage #2: With dihydrogen peroxide In water; dimethyl sulfoxide at 20℃; for 7h; Green chemistry;	85%
With sodium hypochlorite In water; tert-butyl alcohol at 0 - 20℃;	225 mg

4-phenylbenzohydrazide (18622-23-6) + iodobenzene (591-50-4) + tert-butylisonitrile (119072-55-8, 7188-38-7) → 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0)

Conditions	Yield
With 1,3-bis-(diphenylphosphino)propane; sodium acetate In N,N-dimethyl-formamide at 130℃; for 3h; Inert atmosphere;	74%

Biphenyl-4-carboxylic acid [1-phenyl-meth-(E)-ylidene]-hydrazide (86268-09-9) → 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0)

Conditions	Yield
With lead dioxide In acetic acid at 90 - 100℃; for 0.5h;	65%

DC-S337 (100989-00-2) → 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0)

Conditions	Yield
With trichlorophosphate
With trichlorophosphate for 10h; Reflux;

C17H16O4 + benzoic acid hydrazide (613-94-5) → 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0)

Conditions	Yield
Multistep reaction;

biphenyl-4-carboxylic acid (92-92-2) → 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0)

Conditions	Yield
Multi-step reaction with 2 steps 1: N-methylimidazole / CH2Cl2; toluene / 0.5 h / 0 - 20 °C View Scheme

benzoic acid hydrazide (613-94-5) → 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0)

Conditions	Yield
Multi-step reaction with 2 steps 1: pyridine 2: POCl3 View Scheme

4-biphenyl-carboxylic acid chloride (14002-51-8) → 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0)

Conditions	Yield
Multi-step reaction with 2 steps 1: pyridine 2: POCl3 View Scheme

methyl 4-phenylbenzoate (720-75-2) → 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0)

Conditions	Yield
Multi-step reaction with 3 steps 1: hydrazine 2: pyridine / Heating 3: trichlorophosphate / 10 h / Reflux View Scheme

4-phenylbenzohydrazide (18622-23-6) → 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0)

Conditions	Yield
Multi-step reaction with 2 steps 1: pyridine / Heating 2: trichlorophosphate / 10 h / Reflux View Scheme

benzoic acid hydrazide (613-94-5) + 4-Phenylbenzaldehyde (3218-36-8) → 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0)

Conditions	Yield
Multi-step reaction with 2 steps 1: tert-butyl alcohol / Reflux 2: sodium hypochlorite / tert-butyl alcohol; water / 0 - 20 °C View Scheme

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 4-(5-phenyl-1,3,4-oxadiazole-2-yl)-biphenyl-4'-yl sulfonic acid (136180-46-6)

Conditions	Yield
With chlorosulfonic acid In dichloromethane for 2h; Heating;	96%

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → biphenyl-4-carboxylic acid (92-92-2)

Conditions	Yield
With hydrogenchloride; hydrogen iodide In acetic acid for 15h; Heating;	90%

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) + acetyl chloride (75-36-5) → 2-(4'-acetylbiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole (128860-87-7)

Conditions	Yield
With aluminium trichloride In dichloromethane for 5h; Heating;	80%

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-(2',4',5'-tribromobiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole (136180-49-9)

Conditions	Yield
With bromine; iron In carbon disulfide for 4h; Heating;	79%

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) + 2-Bromoacetyl bromide (598-21-0) → 2-(4'-bromoacetylbiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole (128860-88-8)

Conditions	Yield
With aluminium trichloride In dichloromethane for 3h; Heating;	68%

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-(4'-nitrobiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole (136180-43-3)

Conditions	Yield
With sulfuric acid; nitric acid In dichloromethane for 2h; Ambient temperature;	65%

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-(4'-bromobiphenyl-4'-yl)-5-phenyl-1,3,4-oxadiazole (136180-48-8)

Conditions	Yield
With N-Bromosuccinimide; sulfuric acid at 60℃; for 4h;	63%

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) + 1-fluoro-4-methyl-1,4-diazoniabicyclo<2.2.2>octane ditetrafluoroborate + methylzinc chloride (5158-46-3) → 2-(4'-methyl-[1,1'-biphenyl]-4-yl)-5-(p-tolyl)-1,3,4-oxadiazole + 2-(4'-methyl-[1,1'-biphenyl]-4-yl)-5-phenyl-1,3,4-oxadiazole

Conditions

Yield

Stage #1: 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole; 1-fluoro-4-methyl-1,4-diazoniabicyclo<2.2.2>octane ditetrafluoroborate With tris(2,2-bipyridine)ruthenium(II) hexafluorophosphate; C20H28N4O2Pd(2+)*2BF4(1-) In acetonitrile at 23℃; for 24h; Sealed tube; Stage #2: methylzinc chloride With 1-methyl-pyrrolidin-2-one; bis(tricyclohexylphosphine)nickel(II) dichloride; tert-butylammonium hexafluorophosphate(V) In tetrahydrofuran at 50℃; for 20h; Negishi Coupling; Sealed tube;

A 5% B 54%

hippuryl chloride (53587-10-3) + 2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 4'-<(benzoylaminomethyl)carbonyl>-4-(5-phenyl-1,3,4-oxadiazol-2-yl)biphenyl (154532-11-3)

Conditions	Yield
With aluminium trichloride In carbon disulfide 1) 1 h, room temperature; 2) reflux, 5.5 h;	47%

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) + CH3COX → 2-(4'-acetylbiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole (128860-87-7)

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-(4'-cyanobiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole (132584-97-5)

Conditions	Yield
Multi-step reaction with 5 steps 2: sodium hypobromite 3: 1.) carbonyldiimidazole, 2.) NH3 / 1.) CH2Cl2, 0.5 h, reflux, 2.) 45 min 4: 76 percent / Lawesson reagent / benzene / 2 h / Heating 5: 64 percent / Lawesson reagent / xylene / 3 h / Heating View Scheme

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-(4'-carboxybiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole (132584-91-9)

Conditions	Yield
Multi-step reaction with 2 steps 2: sodium hypobromite View Scheme

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-(4'-aminocarbonylbiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole (132584-94-2)

Conditions	Yield
Multi-step reaction with 3 steps 2: sodium hypobromite 3: 1.) carbonyldiimidazole, 2.) NH3 / 1.) CH2Cl2, 0.5 h, reflux, 2.) 45 min View Scheme

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-(4'-aminothiocarbonylbiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole (132584-98-6)

Conditions	Yield
Multi-step reaction with 4 steps 2: sodium hypobromite 3: 1.) carbonyldiimidazole, 2.) NH3 / 1.) CH2Cl2, 0.5 h, reflux, 2.) 45 min 4: 76 percent / Lawesson reagent / benzene / 2 h / Heating View Scheme

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-Phenyl-5-[4'-(4-phenyl-thiazol-2-yl)-biphenyl-4-yl]-[1,3,4]oxadiazole

Conditions	Yield
Multi-step reaction with 5 steps 2: sodium hypobromite 3: 1.) carbonyldiimidazole, 2.) NH3 / 1.) CH2Cl2, 0.5 h, reflux, 2.) 45 min 4: 76 percent / Lawesson reagent / benzene / 2 h / Heating 5: 62 percent / dioxane / 7.5 h / Heating View Scheme

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-Phenyl-5-[4'-(4-p-tolyl-thiazol-2-yl)-biphenyl-4-yl]-[1,3,4]oxadiazole

Conditions	Yield
Multi-step reaction with 5 steps 2: sodium hypobromite 3: 1.) carbonyldiimidazole, 2.) NH3 / 1.) CH2Cl2, 0.5 h, reflux, 2.) 45 min 4: 76 percent / Lawesson reagent / benzene / 2 h / Heating 5: 41 percent / dioxane / 7 h / Heating View Scheme

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-{4'-[4-(4-Bromo-phenyl)-thiazol-2-yl]-biphenyl-4-yl}-5-phenyl-[1,3,4]oxadiazole

Conditions	Yield
Multi-step reaction with 5 steps 2: sodium hypobromite 3: 1.) carbonyldiimidazole, 2.) NH3 / 1.) CH2Cl2, 0.5 h, reflux, 2.) 45 min 4: 76 percent / Lawesson reagent / benzene / 2 h / Heating 5: 28 percent / dioxane / 5 h / Heating View Scheme

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-[4'-(4-Naphthalen-2-yl-thiazol-2-yl)-biphenyl-4-yl]-5-phenyl-[1,3,4]oxadiazole

Conditions	Yield
Multi-step reaction with 5 steps 2: sodium hypobromite 3: 1.) carbonyldiimidazole, 2.) NH3 / 1.) CH2Cl2, 0.5 h, reflux, 2.) 45 min 4: 76 percent / Lawesson reagent / benzene / 2 h / Heating 5: 33 percent / dioxane / 7 h / Heating View Scheme

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-[4'-(4-Naphthalen-1-yl-thiazol-2-yl)-biphenyl-4-yl]-5-phenyl-[1,3,4]oxadiazole

Conditions	Yield
Multi-step reaction with 5 steps 2: sodium hypobromite 3: 1.) carbonyldiimidazole, 2.) NH3 / 1.) CH2Cl2, 0.5 h, reflux, 2.) 45 min 4: 76 percent / Lawesson reagent / benzene / 2 h / Heating 5: 30 percent / dioxane / 4.5 h / Heating View Scheme

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-{4'-[4-(4-Methoxy-phenyl)-thiazol-2-yl]-biphenyl-4-yl}-5-phenyl-[1,3,4]oxadiazole

Conditions	Yield
Multi-step reaction with 5 steps 2: sodium hypobromite 3: 1.) carbonyldiimidazole, 2.) NH3 / 1.) CH2Cl2, 0.5 h, reflux, 2.) 45 min 4: 76 percent / Lawesson reagent / benzene / 2 h / Heating 5: 42 percent / dioxane / 4 h / Heating View Scheme

2-biphenyl-4-yl-5-phenyl-[1,3,4]oxadiazole (852-38-0) → 2-[4'-(4-Biphenyl-4-yl-thiazol-2-yl)-biphenyl-4-yl]-5-phenyl-[1,3,4]oxadiazole

Conditions	Yield
Multi-step reaction with 5 steps 2: sodium hypobromite 3: 1.) carbonyldiimidazole, 2.) NH3 / 1.) CH2Cl2, 0.5 h, reflux, 2.) 45 min 4: 76 percent / Lawesson reagent / benzene / 2 h / Heating 5: 26 percent / dioxane / 9 h / Heating View Scheme

Upstream product

• 100989-00-2 DC-S₃₃₇ 
• 86268-09-9 Biphenyl-4-carboxylic acid [1-phenyl-meth-(E)-ylidene]-hydrazide 
• 613-94-5 benzoic acid hydrazide 
• 92-92-2 biphenyl-4-carboxylic acid 
• 14002-51-8 4-biphenyl-carboxylic acid chloride 
• 18622-23-6 4-phenylbenzohydrazide 
• 412956-37-7 C₂₀H₁₆N₂O 
• 591-50-4 iodobenzene 
• 119072-55-8 tert-butylisonitrile 
• 3218-36-8 4-Phenylbenzaldehyde 
• 720-75-2 methyl 4-phenylbenzoate 

Downstream Products

• 136180-47-7 4-(5-phenyl-1,3,4-oxadiazole-2-yl)-biphenyl-4'-yl-sulfonyl chloride 
• 136180-45-5 2-(4'-acetylaminobiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole 
• 136180-41-1 2-(4'-acetylbiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole hydrazone 
• 136180-40-0 2-(4'-(1-hydroxyethyl)biphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole 
• 136180-44-4 2-(4'-aminobiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole 
• 136180-42-2 2-(4'-vinylbiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole 
• 114691-92-8 4-acetyl-4'-biphenylcarboxylic acid 
• 5731-13-5 4-(4-ethylphenyl)benzoic acid 
• 5730-78-9 4-(4-aminophenyl)benzoic acid 
• 132584-98-6 2-(4'-aminothiocarbonylbiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole 
• 132584-94-2 2-(4'-aminocarbonylbiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole 
• 132584-91-9 2-(4'-carboxybiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole 
• 132584-97-5 2-(4'-cyanobiphenyl-4-yl)-5-phenyl-1,3,4-oxadiazole 

Relevant academic research and scientific papers

Sodium hypochlorite-mediated synthesis of 2,5-disubstituted 1,3,4-oxadiazoles from hydrazides and aldehydes

[Figure not available: see fulltext.] A simple and convenient method for the synthesis of 2,5-disubstituted 1,3,4-oxadiazoles has been developed. Structurally divergent symmetrical and unsymmetrical 2,5-disubstituted 1,3,4-oxadiazoles can be obtained in moderate to high yields via NaOCl-mediated oxidative cyclization of N-acylhydrazones, generated in situ from aliphatic and aromatic hydrazides and aldehydes.

Palladium-catalyzed one-pot synthesis of diazoles via tert-butyl isocyanide insertion

An efficient one-pot palladium-catalyzed reaction for the synthesis of diazoles from readily available hydrazides and aryl halide via isocyanide insertion/cyclization sequence has been developed. This methodology efficiently constructs diazoles in good to excellent yields with the advantages of wide functional group tolerance and operational simplicity.

Iodine-catalysed oxidative cyclisation of acylhydrazones to 2,5-substituted 1,3,4-oxadiazoles

An environmentally benign synthesis of 2,5-disubstituted 1,3,4-oxadiazoles has been developed starting from N-aroylhydrazones and N-acetylhydrazones at room or ambient temperature using a catalytic quantity of iodine in the presence of an aqueous hydrogen peroxide oxidant.

17O NMR studies of substituted 1,3,4-oxadiazoles

Three series of substituted 1,3,4-oxadiazoles were studied by 17O NMR spectroscopy. Chemical shifts values were correlated with empirical Hammett parameters as well as calculated bond lengths and chemical shielding values.

A simple and efficient one step synthesis of 1,3,4-oxadiazoles utilizing polymer-supported reagents and microwave heating

1,3,4-Oxadiazoles can be rapidly and efficiently synthesized from a variety of carboxylic acids and acid hydrazides in one simple step. The use of commercially available PS-PPh3 resin combined with microwave heating delivered the product 1,3,4-oxadiazoles in high yields and purities.

1,3,4-Oxadiazole formation as traceless release in solid phase organic synthesis

Oxadiazoles were generated upon a dehydrative cyclization reaction with 2-acyl hydrazides bound to the polymeric support via one of their N atoms using TFAA as a dehydration agent.

Oxydations d'hydrazones par le bioxyde de plomb: nouvelles syntheses d'oxadiazoles-1,3,4 et de derives de l'amino-4 triazol-1,2,4 one-5

Aromatic aldehyde aroylhydrazones when oxidized with lead dioxide, in acetic acid, gave quickly the corresponding 1,3,4-oxadiazoles in good yields.Aromatic aldehyde carbodihydrazones on the other hand, gave derivatives of 4-amino-3-aryl-1,2,4-triazol-5-ones, in dimethylformamide as solvent.To explain these results, some radical mechanisms are proposed.