4233-33-4

Basic information

• Product Name: 4-PHENYL-1,2,4-TRIAZOLINE-3,5-DIONE
• Synonyms: AURORA KA-3851;3,5-DIHYDRO-4-PHENYL-4ETA-1,2,4-TRIAZOLE-3,5-DIONE;3,5-DIHYDRO-4-PHENYL-4H-1,2,4-TRIAZOLE-3,5-DIONE;4-PHENYL-3H-1,2,4-TRIAZOLINE-3,5-DIONE;4-PHENYL-1,2,4-TRIAZOLINE-3,5-DIONE;4-PHENYL-3,5-DIHYDRO-4ETA-1,2,4-TRIAZOLE-3,5-DIONE;PTAD;4-Phenyl-1,2,4-triazole-3,5-dione
• CAS NO: 4233-33-4
• Molecular Formula: C₈H₅N₃O₂
• Molecular Weight: 175.14
• EINECS: 224-191-7
• Product Categories: Amino Acids & Derivatives;Aromatics;Heterocycles
• Mol File: 4233-33-4.mol
• Article Data: 63

Chemical Properties

• Melting Point: 165-170 °C (dec.)(lit.)
• Boiling Point: 263.812 °C at 760 mmHg
• Flash Point: 113.35 °C
• Appearance: /
• Density: 1.471 g/cm³
• Vapor Pressure: 0.0101mmHg at 25°C
• Refractive Index: 1.701
• Storage Temp.: 2-8°C
• Solubility: Chloroform (Sparingly), DMSO (Slightly), Ethyl Acetate (Slightly), Methanol (Sli
• PKA: -1.71±0.20(Predicted)
• BRN: 141548
• CAS DataBase Reference: 4-PHENYL-1,2,4-TRIAZOLINE-3,5-DIONE(CAS DataBase Reference)
• NIST Chemistry Reference: 4-PHENYL-1,2,4-TRIAZOLINE-3,5-DIONE(4233-33-4)
• EPA Substance Registry System: 4-PHENYL-1,2,4-TRIAZOLINE-3,5-DIONE(4233-33-4)

Safety Data

• Safety Statements: 22-24/25
• WGK Germany: 3
• Hazardous Substances Data: 4233-33-4(Hazardous Substances Data)

Usage

Chemical Properties

4-PHENYL-1,2,4-TRIAZOLINE-3,5-DIONE is Red Solid

Uses

Different sources of media describe the Uses of 4233-33-4 differently. You can refer to the following data:
1. 4-PHENYL-1,2,4-TRIAZOLINE-3,5-DIONE is used in the methods for determining levels of 1,25 dihydroxyvitamin d2 and d3 in biological and food samples and dietary supplements.
2. 4-Phenyl-1,2,4-triazoline-3,5-dione (PTAD) can be used as an efficient and selective reagent for the oxidation of thiols to disulfides.It can also be used:???????As a dehydrogenating agent to synthesize annulated dihydropyridazines by inverse [4+2] cycloaddition reaction between cyclic alkenes and 1,2,4,5-tetrazines.???????As a dienophile to synthesize cycloaddition products by fast hetero-Diels?Alder reactions.???????As an efficient oxidizing agent for the synthesis of pyridine derivatives from 1,4-dihydropyridines.In the synthesis of urazoles via [3+2] cycloaddition with allylsilanes.
3. 4-Phenyl-1,2,4-triazoline-3,5-dione may be used as a derivatizing reagent for the determination of trace levels of 25-hydroxyvitamin D and its C-3 epimer in biological samples and cholecalciferol (vitamin D3) in fortified infant formula, milk and milk powder using liquid chromatography–tandem mass spectrometry (LC–MS/MS)technique.

Synthesis Reference(s)

Synthetic Communications, 17, p. 409, 1987 DOI: 10.1080/00397918708063918

General Description

4-Phenyl-1,2,4-triazoline-3,5-dione, also known as Cookson reagent, is a strong dienophile, which gives a stable Diels-Alder adduct quantitatively within a short time and under mild conditions. It is commonly used as a protecting group of the diene moiety for the synthesis of vitamin D3 (VD3)-related compounds.

Purification Methods

PTAD forms carmine red needles by sublimation (ice cold finger) at 100o/0.1mm, and/or by recrystallisation from EtOH. IR: 1760 and 1780 cm-1 . [Cookson et al. Org Synth 51 121 1971, Moore max et al. J Org Chem 39 3700 1974, Beilstein 26 I 57, 26 III/IV 540.]

InChI:InChI=1/C8H5N3O2/c12-7-9-10-8(13)11(7)6-4-2-1-3-5-6/h1-5H

Synthetic route

4-Phenylurazole (15988-11-1) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4)

Conditions	Yield
With tetrabutylammonium periodite In acetone at 20℃; for 0.5h;	100%
With SiO2-supported HNO3 In dichloromethane at 20℃; for 0.583333h; chemoselective reaction;	99%
With chlorine In ethyl acetate for 18h;	98%

10,11-Dimethylen-4-phenyl-2,4,6-triazatricyclo<5.2.2.02,6>undec-8-en-3,5-dion (86814-89-3) + 4-methyl-1,2,4-triazoline-3,5-dione (13274-43-6) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 1,2,3,4-Tetrahydro-N-phenyl-2,3-phthalazindicarboximid (30168-21-9) + 1,2,3,4-Tetrahydro-N-methyl-2,3-phthalazindicarboximid (86814-91-7)

Conditions	Yield
In dichloromethane -78 deg C to 10 deg C;	A n/a B 2% C 95%

acetoxy-(3-acetoxy-5-oxo-4-phenyl-4,5-dihydro-[1,2,4]triazol-1-yl)-acetic acid ethyl ester → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4)

Conditions	Yield
With tert-butylhypochlorite; sodium carbonate; sodium sulfate In ethyl acetate at 0℃;

4-phenylurazole → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4)

Conditions	Yield
With tert-butylhypochlorite In ethyl acetate for 0.666667h; Ambient temperature;

disilver salt of hydrazodicarboxanil → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4)

Conditions	Yield
With iodine

phenyl isocyanate (103-71-9) + diluted benzene → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4)

Conditions	Yield
Multi-step reaction with 3 steps 1: benzene / 20-25 deg C, 2 h; reflux, 2 h 2: KOH / H2O / 2 h 3: anhydrous Na2SO4, N2O4 / CH2Cl2 / 0 °C View Scheme

ethyl 2-(tert-butylcarbamoyl)hydrazine-1-carboxylate (17696-94-5) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4)

Conditions	Yield
Multi-step reaction with 2 steps 1: KOH / H2O / 2 h 2: anhydrous Na2SO4, N2O4 / CH2Cl2 / 0 °C View Scheme

2-diphenylmethyliumyl-3,5-dioxo-4-phenyl-1,2,4-triazolidin-1-ide (2693-32-5) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4)

Conditions	Yield
Multi-step reaction with 2 steps 1: atmospheric moisture / storage conditions 2: t-butyl hypochlorite / CH2Cl2 / 0 °C View Scheme

C23H17N3O2 (1330068-60-4) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4)

Conditions	Yield
Multi-step reaction with 3 steps 1: chloroform-d1 / 50 °C / Darkness 2: chloroform-d1 / 25 °C / Darkness 3: chloroform-d1 / 50 °C / Darkness View Scheme

C23H17N3O2 (1330068-60-4) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9-methylanthracene (779-02-2)

Conditions	Yield
In chloroform-d1 at 50℃; Equilibrium constant; Temperature; retro-Diels-Alder Reaction; Darkness;
In toluene at 25℃; under 760.051 Torr; Equilibrium constant;

C34H23N3O2 (1330068-44-4) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4)

Conditions	Yield
Multi-step reaction with 3 steps 1: chloroform-d1 / 50 °C / Darkness 2: chloroform-d1 / 25 °C / Darkness 3: chloroform-d1 / 50 °C / Darkness View Scheme
Multi-step reaction with 3 steps 1: chloroform-d1 / 50 °C / Darkness 2: chloroform-d1 / 25 °C / Darkness 3: chloroform-d1 / 50 °C / Darkness View Scheme

C34H23N3O2 (1330068-44-4) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9,10-dimethylanthracene (781-43-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: chloroform-d1 / 25 °C / Darkness 2: chloroform-d1 / 50 °C / Darkness View Scheme

C34H23N3O2 (1330068-44-4) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9,10-diphenylanthracene (1499-10-1)

Conditions	Yield
In chloroform-d1 at 50℃; Equilibrium constant; Temperature; retro-Diels-Alder Reaction; Darkness;

C22H13Cl2N3O2 (1330068-62-6) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4)

Conditions	Yield
Multi-step reaction with 3 steps 1: chloroform-d1 / 50 °C / Darkness 2: chloroform-d1 / 25 °C / Darkness 3: chloroform-d1 / 50 °C / Darkness View Scheme

C22H13Cl2N3O2 (1330068-62-6) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9,10-dichloroanthracene (605-48-1)

Conditions	Yield
In chloroform-d1 at 50℃; Equilibrium constant; Temperature; retro-Diels-Alder Reaction; Darkness;
In toluene at 25℃; under 760.051 Torr; Equilibrium constant;

9,10-dimethyl-14-phenyl-9,10-dihydro-9,10-[1,2]epi[1,2,4]triazolo-anthracene-13,15-dione (13715-59-8) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9,10-dimethylanthracene (781-43-1)

Conditions	Yield
In chloroform-d1 at 50℃; Equilibrium constant; Temperature; retro-Diels-Alder Reaction; Darkness;
In toluene at 25℃; under 760.051 Torr; Equilibrium constant;

9,10-dimethyl-14-phenyl-9,10-dihydro-9,10-[1,2]epi[1,2,4]triazolo-anthracene-13,15-dione (13715-59-8) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9,10-diphenylanthracene (1499-10-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: chloroform-d1 / 25 °C / Darkness 2: chloroform-d1 / 50 °C / Darkness View Scheme

9,10-(4’-phenyl)urazolo-9,10-dihydroanthracene (10316-56-0) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + anthracene (120-12-7)

Conditions	Yield
In chloroform-d1 at 50℃; Equilibrium constant; Temperature; retro-Diels-Alder Reaction; Darkness;
In toluene at 25℃; under 760.051 Torr; Equilibrium constant; Solvent;

9,10-(4’-phenyl)urazolo-9,10-dihydroanthracene (10316-56-0) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9,10-dimethylanthracene (781-43-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: chloroform-d1 / 25 °C / Darkness 2: chloroform-d1 / 50 °C / Darkness View Scheme

9,10-(4’-phenyl)urazolo-9,10-dihydroanthracene (10316-56-0) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9,10-diphenylanthracene (1499-10-1)

Conditions	Yield
Multi-step reaction with 3 steps 1: chloroform-d1 / 25 °C / Darkness 2: chloroform-d1 / 25 °C / Darkness 3: chloroform-d1 / 50 °C / Darkness View Scheme

1-(2-hydroxy-5-methylphenyl)-4-phenyl-1,2,4-triazolidine-3,5-dione (1207170-30-6) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4)

Conditions	Yield
With hydrogenchloride; water In methanol at 20℃; for 12h; Inert atmosphere;

3-(benzylthio)-1-phenylpyrrolidine-2,5-dione (95498-43-4) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4)

Conditions	Yield
With hydrogenchloride; water In methanol at 20℃; for 12h; Inert atmosphere;

(1R,8S)-4,15-dimethyl-11-phenyl-9,11,13-triazatetracyclo[6.5.2.02,7.09,13]pentadeca-2,4,6,14-tetraene-10,12-dione → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 2.6-dimethylnaphthalene (581-42-0)

Conditions	Yield
at 20℃; Equilibrium constant; Thermodynamic data; Kinetics; Activation energy;

3,10,15-triphenyl-13,15,17-triazapentacyclo[10.5.2.02,11.04.9.013,17]nonadeca-2,4(9),5,7,10,18-hexaene-14,16-dione → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9,10-diphenylanthracene (1499-10-1)

Conditions	Yield
With trans,trans-1,4-Diphenyl-1,3-butadiene at 20℃; Thermodynamic data; Kinetics; Activation energy;
With trans,trans-1,4-Diphenyl-1,3-butadiene In toluene at 25℃; under 760.051 Torr; Equilibrium constant; Kinetics; Thermodynamic data; Temperature; Pressure;

C22H14ClN3O2 (1450893-71-6) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9-chloroanthracene (716-53-0)

Conditions	Yield
In toluene at 25℃; under 760.051 Torr; Equilibrium constant; Temperature;

C28H19N3O2 (1450893-72-7) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9-phenylanthracene (602-55-1)

Conditions	Yield
In toluene at 25℃; under 760.051 Torr; Equilibrium constant; Temperature;

9,10-dimethoxy-14-phenyl-9,10-dihydro-9,10-[1,2]epi[1,2,4]triazolo-anthracene-13,15-dione (13715-60-1) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9,10-dimethoxyanthracene (2395-97-3)

Conditions	Yield
In toluene at 25℃; under 760.051 Torr; Equilibrium constant;

C23H14N4O2 → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9-cyanoanthracene (1210-12-4)

Conditions	Yield
In toluene at 25℃; under 760.051 Torr; Equilibrium constant; Temperature;

C28H33N3O2 (90461-90-8) → 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + adamantylidene-adamantane (30541-56-1)

Conditions	Yield
In toluene Equilibrium constant;

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 5-ethoxy-2-phenyl-1,3-oxazole (25755-93-5) → 2,5-diphenyl-7-carbethoxy-2,4,6,8-tetraaza <3.3.1>bicyclooct-5-ene-1,3-dione (125422-61-9)

Conditions	Yield
In benzene at 20℃; for 0.2h;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 1-methyleneindane (1194-56-5) → 1-(3-1H-indenylmethyl)-4-phenyl-1,2,4-triazolidine-3,5-dione (99532-26-0)

Conditions	Yield
In dichloromethane for 2h; Ambient temperature;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + anthracene (120-12-7) → 9,10-(4’-phenyl)urazolo-9,10-dihydroanthracene (10316-56-0)

Conditions	Yield
In toluene at 20℃; for 2h;	100%
In chloroform-d1 at 25℃; Equilibrium constant; Temperature; Diels-Alder reaction; Darkness;	84 %Spectr.
In chloroform at 24.84℃; Kinetics; Solvent; Diels-Alder Cycloaddition;

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + adamantylidene-adamantane (30541-56-1) → C28H33N3O2 (90461-90-8)

Conditions	Yield
In benzene at 20℃; for 2h;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + bicyclopentylidene (16189-35-8) → 1-(1-cyclopent-1-enylcyclopentyl)-4-phenyl-1,2-dihydro-1,2,4-triazole-3,5-dione (135084-70-7)

Conditions	Yield
In dichloromethane Ambient temperature;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 7-methylenecycloocta-1,3,5-triene (2570-13-0) → 5-phenyl-3,5,7-triazatricyclo<6.5.1.03,7>tetradeca-9,11,13-triene-4,6-dione (75437-27-3)

Conditions	Yield
Mechanism;	100%
In acetone for 0.0833333h; Ambient temperature;	97%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 5-(methoxycarbonyl)-2-phenyl<1,2,4>triazolo<1,2-a>pyridazine-1,3-dione (88180-59-0) → C22H16N6O6 (88200-31-1)

Conditions	Yield
In acetone Ambient temperature;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + diisopropylidenethiirane oxide (81355-46-6) → 2,2,6,6-Tetramethyl-1-oxo-4-phenyl-2,6-dihydro-1H-1λ4-thia-2a,4,5a-triaza-cyclopropa[f]indene-3,5-dione (82613-76-1)

Conditions	Yield
In dichloromethane Ambient temperature;	100%
In dichloromethane Ambient temperature;

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 2-azanorbornadiene (83953-54-2) → hydrogen cyanide (74-90-8) + 4-phenyl-2,4,6-triazatricyclo[3.2.1.0(2,6)]dec-8-ene-3,5-dione (15971-63-8, 137121-69-8, 137121-70-1)

Conditions	Yield
In tetrahydrofuran-d8	A n/a B 100%
In tetrahydrofuran-d8	A n/a B 100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + C20H18 (65879-08-5) → C28H23N3O2 (125512-66-5)

Conditions	Yield
In dichloromethane at 0℃;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + n-Hexyl 11,13-dioxo-12-aza<4.4.3>propella-2,4,7,9-tetraene-12-acetate (78388-45-1) → C28H28N4O6 (78388-46-2)

Conditions	Yield
In dichloromethane Ambient temperature;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 2-ethyl-5-methoxy-4-(p-nitrophenyl)oxazole (93961-31-0) → 3-Ethyl-1-(4-nitro-phenyl)-5,7-dioxo-6-phenyl-6,7-dihydro-1H,5H-[1,2,4]triazolo[1,2-a][1,2,4]triazole-1-carboxylic acid methyl ester (121031-29-6)

Conditions	Yield
In acetonitrile Ambient temperature;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + ethyl 1-oxo-4,6,6-trimethyl-2,4-cyclohexadiene-3-carboxylate (109216-99-1) → ethyl 2-phenyl-7,10,10-trimethyl-1,3,11-trioxo-5,8-etheno-2,3,5,8-tetrahydro-1H-<1,2,4>triazolo<1,2-a>pyridazine-6-carboxylate (109241-75-0)

Conditions	Yield
In dichloromethane Ambient temperature;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + cyclohexene (110-83-8) → 1-(cyclohex-2-enyl)-4-phenyl-1,2,4-triazolidine-3,5-dione (15971-69-4)

Conditions	Yield
In dichloromethane	100%
In dichloromethane Ambient temperature;	89%
In benzene at 25℃; Rate constant; other solvent;
In benzene at 25℃; Rate constant; other solvent: CH2Cl2;
In toluene at 25℃; under 1490400 Torr; Kinetics; Temperature; Pressure; Concentration;

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) → 4-Phenylurazole (15988-11-1)

Conditions	Yield
With thiophenol In toluene at 20℃; for 5h; Product distribution; Further Variations:; Reagents; Solvents;	100%
With hydrazine hydrate In acetonitrile at 20℃; for 0.0166667h;	99%
With acetic acid; sodium iodide In acetone for 0.0833333h;	76%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 4-hydroxy-8-methyl-2-oxo-7,8-dihydro-2H,6H-pyrrolo<2,1-b><1,3>thiazinium hydroxide inner salt (166535-68-8) → 10-methyl-2-phenyl-2,3,5,6,8,9-hexahydro-1H-pyrrolo<2,1-c>-1,2,4-triazolo<1,2-a><1,2,4>triazine-1,3,5-trione

Conditions	Yield
In diethyl ether for 6h; Ambient temperature;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + Adamantylidenecyclopentadiene (16668-82-9) → 10-Adamantylidene-2,4,6-triazatricyclo<5.2.1.02.6>dec-8-ene-3,5-dione

Conditions	Yield
In dichloromethane-d2 at -78℃; for 1h;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + cyclopenta-1,3-diene (542-92-7) → 2-phenyl-4,5,8,9-tetrahydro-5,8-methano[1,2,4]triazolo[1,2-a]pyridazine-1,3-dione (15971-63-8)

Conditions	Yield
In dichloromethane at -10℃;	100%
With lithium perchlorate In acetonitrile Cycloaddition;	75%
In toluene at 24.5℃; Kinetics; Thermodynamic data; Solvent; Diels-Alder Cycloaddition;

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + cyclohexa-1,3-diene (1165952-91-9) → 4-phenyl-2,4,6-triazatricyclo<5.2.2.02,6>undec-8-ene-3,5-dione (10316-53-7)

Conditions	Yield
In dichloromethane at -10℃;	100%
In sulfuric acid; acetonitrile Cycloaddition;	90%
In dichloromethane at 20℃; for 2h; Inert atmosphere;	115 mg

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 4-hydroxy-3,8,8-trimethyl-2-oxo-3,4,6,7-tetrahydro-2H,6H-pyrrolo<2,1-b><1,3>-thiazinium hydroxide inner salt (153616-70-7) → 9-phenyl-1-thia-3,7,7-trimethyl-octahydro-4a,7b,9,10a-tetraaza-ethano-as-indacen-2,4,8,10-tetraone

Conditions	Yield
In acetonitrile at -40℃; for 0.166667h;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + isoprene (78-79-5) → 3-methyl-8-phenyl-1,6,8-triazabicyclo[4.3.0]non-3-ene-7,9-dione (10316-49-1)

Conditions	Yield
In dichloromethane at -10℃;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + Methyl (11,11a-dihydro-4aH-4a,11a-methanoindeno[1,2-a]azulen-10-yl)carboxylate (199180-81-9) → C28H21N3O4

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

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 1-Ethyl-5,6-diphenyl-1H-pyrazin-2-one (78174-92-2) → 8-Ethyl-4,7,11-triphenyl-2,4,6,8,10-pentaaza-tricyclo[5.2.2.02,6]undec-10-ene-3,5,9-trione

Conditions	Yield
In dichloromethane for 0.5h; Ambient temperature;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + C21H14 → C29H19N3O2

Conditions	Yield
at 3℃; for 2h; Product distribution; determination of ratio syn-endo or anti-endo attack;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + C21H14 → C29H19N3O2

Conditions	Yield
at 3℃; for 2h;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + C21H14 → C29H19N3O2

Conditions	Yield
at 3℃; for 2h; Product distribution; determination of ratio syn-endo or anti-endo attack;	100%
at 3℃; for 2h;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + 9,10-dimethylenetricyclo[6.2.1.02,7]undeca-2,4,6-triene (56305-84-1) → 6-phenyl-4,6,8-triazapentacyclo[9.6.1.02,10.04,8.012,17]octadeca-2(10),12(17),13,15-tetraene-5,7-dione (208457-12-9)

Conditions	Yield
In chloroform for 0.5h; Ambient temperature;	100%

4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) + (E,E)-1-l-menthyloxy-1,3-octadiene (197970-24-4) → cis-5-butyl-2-phenyl-8-(l-menthyloxy)-5,8-dihydro-[1,2,4]triazolo[1,2-a]pyridazine-1,3-dione

Conditions	Yield
In tetrahydrofuran at -25℃; Diels-Alder cycloaddition;	100%

(+/-)-(3R)-(1E)-cyclohexenyl-1-(p-tolylsulfonyl)hept-1-en-3-ol + 4-Phenyl-1,2,4-triazolidine-3,5-dione (4233-33-4) → (+/-)-(5R,10aR)-5-[(1R)-hydroxypentyl]-2-phenyl-6-(p-tolylsulfonyl)-8,9,10,10a-tetrahydro-2H-[1,2,4]triazolo[1,2-a]cinnoline-1,3(5H,7H)-dione

Conditions	Yield
In toluene at -78 - 20℃; for 12h; Diels-Alder cycloaddition;	100%

Upstream product

• 15988-11-1 4-Phenylurazole 
• 1207170-30-6 1-(2-hydroxy-5-methylphenyl)-4-phenyl-1,2,4-triazolidine-3,5-dione 
• 95498-43-4 3-(benzylthio)-1-phenylpyrrolidine-2,5-dione 
• 68315-30-0 (Z)-N-benzylidene-2-methylpropan-2-amine oxide 
• 90461-90-8 C₂₈H₃₃N₃O₂ 
• 13715-60-1 9,10-dimethoxy-14-phenyl-9,10-dihydro-9,10-[1,2]epi[1,2,4]triazolo-anthracene-13,15-dione 
• 1450893-72-7 C₂₈H₁₉N₃O₂ 
• 1450893-71-6 C₂₂H₁₄ClN₃O₂ 
• 10316-56-0 9,10-(4’-phenyl)urazolo-9,10-dihydroanthracene 
• 13715-59-8 9,10-dimethyl-14-phenyl-9,10-dihydro-9,10-[1,2]epi[1,2,4]triazolo-anthracene-13,15-dione 
• 1330068-62-6 C₂₂H₁₃Cl₂N₃O₂ 
• 1330068-44-4 C₃₄H₂₃N₃O₂ 
• 1330068-60-4 C₂₃H₁₇N₃O₂ 
• 2693-32-5 2-diphenylmethyliumyl-3,5-dioxo-4-phenyl-1,2,4-triazolidin-1-ide 

Downstream Products

• 56655-37-9 1-(1,1-dimethyl-2,3-dihydro-1H-silol-3-yl)-4-phenyl-[1,2,4]triazolidine-3,5-dione 
• 53631-87-1 5,9a-dihydro-2-phenylthieno<3,2-c><1,2,4>triazolo<1,2-a>pyridazine-1,3-dione 
• 91319-36-7 5,6-dihydro-2-phenyl-6-(3,5-dioxo-4-phenyl-1,2,4-triazolin-1-yl)thieno<3,2-c><1,2,4>triazolo<1,2-a>pyridazine-1,3-dione 
• 100084-44-4 1-Methyl-4-phenyl-2,4,6-triazatricyclo<5.2.2.0^2,6>undec-8-en-3,5,10-trion 
• 100164-13-4 (1S^*,10R^*)-10-Hydroxy-10-methyl-4-phenyl-2,4,6-triazatricyclo<5.2.2.0^2,6>undec-8-en-3,5-dion 
• 100084-49-9 (1S^*,10S^*)-10-Hydroxy-10-methyl-4-phenyl-2,4,6-triazatricyclo<5.2.2.0^2,6>undec-8-en-3,5-dion 
• 100164-23-6 (1S^*,10R^*)-10-Hydroxy-1,10-dimethyl-4-phenyl-2,4,6-triazatricyclo<5.2.2.0^2,6>undec-8-en-3,5-dion 
• 100084-51-3 (1S^*,10S^*)-10-Hydroxy-1,10-dimethyl-4-phenyl-2,4,6-triazatricyclo<5.2.2.0^2,6>undec-8-en-3,5-dion 
• 74746-21-7 7-acetyl-6,7-dihydro-2-phenyl-2H-pyrazolo<1,2-a>-1,2,4-triazole-1,3,5-trione 
• 107798-94-7 1-(2-methyl-3-indolyl)-4-phenylurazole 
• 123209-00-7 3-(4-phenylurazolyl)-2-oxoindole 
• 63376-58-9 5-(4-phenyl-3,5-dioxo-1,2,4-triazolidin-1-yl)-1,3-dimethyluracil 
• 65010-29-9 4-phenyl-1-<3-(4-methyl-5-phenyl-1,2-dithiolio)>urazolide 
• 123209-01-8 2-(4-phenylurazolyl)-1,2-diphenylethanone 

Relevant articles and documents

Oxidative dehydrogenation of 4-arylurazoles

4-Arylurazoles are selectively oxidized with Fe2(NO 3)3·9H2O to the corresponding Δ1-1,2,4-triazoline-3,5-diones.

METHOD FOR PRODUCING SOLID TRIAZOLINEDIONE COMPOUND, SOLID TRIAZOLINEDIONE COMPOUND, AND METHOD FOR PRODUCING TRIAZOLINEDIONE COMPOUND

Provided are a method for separating a DAPTAD-containing triazolinedione compound in solid form from a reaction solution, a separated solid triazolinedione compound, and a novel method for producing a triazolinedione compound. A triazolinedione solution in which a DAPTAD-containing triazolinedione compound is dissolved is brought into contact with a C5-15 hydrocarbon-based poor solvent to obtain a solid triazolinedione compound. Also, a triazolinedione compound is oxidized using an oxidizing agent that does not produce acid as a byproduct to obtain a triazolinedione compound.

Melamine-(H2SO4)3/Melamine-(HNO3)3 Instead of H2SO4/HNO3: Benign System for Oxidation/Nitration Reactions from in situ NO2 +

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[2π + 2π]-Cycloaddition of biadamantylidene to 4-phenyl-3H-1,2,4-triazole-3,5(4H)-dione. Effects of temperature, high pressure, and solvent

The effects of temperature, solvent nature, and high hydrostatic pressure on the rate of the reaction of biadamantylidene with 4-phenyl-3H-1,2,4-triazole-3,5(4H)-dione have been estimated. Significant shielding of the C=C double bond in biadamantylidene is responsible for the high entropy and volume of activation. Quantitative yield of the reaction in the temperature range 25?45°C is related to its exothermicity. The rate of the [2π + 2π]-cycloaddition unexpectedly weakly depends on the solvent polarity, which makes it radically different from the [2π + 2π]-reaction with tetracyanoethylene.