219715-62-5

Basic information

• Product Name: 2-Amino-5,8-dimethoxy-[1,2,4]triazolo[1,5-c]pyrimidine
• Synonyms: 2-Amino-5,8-dimethoxy-[1,2,4]triazolo[1,5-c]pyrimidine;5,8-Dimethoxy-[1,2,4]triazolo[1,5-c]pyrimidin-2-amine
• CAS NO: 219715-62-5
• Molecular Formula: C₇H₉N₅O₂
• Molecular Weight: 195.17866
• Mol File: 219715-62-5.mol
• Article Data: 9

Chemical Properties

• Melting Point: 201-203℃
• Appearance: /
• Density: 1.61
• Storage Temp.: under inert gas (nitrogen or Argon) at 2–8 °C
• PKA: 2.66±0.30(Predicted)
• CAS DataBase Reference: 2-Amino-5,8-dimethoxy-[1,2,4]triazolo[1,5-c]pyrimidine(CAS DataBase Reference)
• NIST Chemistry Reference: 2-Amino-5,8-dimethoxy-[1,2,4]triazolo[1,5-c]pyrimidine(219715-62-5)
• EPA Substance Registry System: 2-Amino-5,8-dimethoxy-[1,2,4]triazolo[1,5-c]pyrimidine(219715-62-5)

Safety Data

• Hazardous Substances Data: 219715-62-5(Hazardous Substances Data)

Usage

Uses

5,8-Dimethoxy[1,2,4]triazolo[1,5-c]pyrimidin-2-amine is an intermediate of Penoxsulam(P274000), which is an acetolactate synthase inhibitor herbicide developed for controlling grasses, sedges, and broadleaf weeds in rice culture.

Synthetic route

3-amino-5,8-dimethoxy[1,2,4]triazolo[4,3-c]pyrimidine → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
With sodium methylate In methanol at 20℃; for 3h;	92.8%
With sodium methylate In methanol	92.8%

4-[4-(2,5-dimethoxypyrimidinyl)] (1350919-13-9) → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
With hydroxylamine hydrochloride; sodium methylate; triethylamine In 1,4-dioxane; methanol at 20 - 30℃;	91.2%

5-chloro-8-methoxy[1,2,4]triazolo[1,5-c]pyrimidin-2-amine (1350919-12-8) + sodium methylate (124-41-4) → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
In methanol; acetonitrile at 20℃; for 1.5h;	88%

2-Chloro-4-hydrazino-5-methoxy-pyrimidine (98021-95-5) → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
With bromocyane; sodium methylate In methanol; acetonitrile; tert-butyl alcohol at 0 - 41℃; for 7h;	82.4%

C14H14N4O4S → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
With hydroxylamine hydrochloride; sodium hydroxide In ethanol; water at 40 - 50℃; for 4.5h; Temperature; Solvent; Concentration;	76.4%

bromocyane (506-68-3) + 2-Chloro-4-hydrazino-5-methoxy-pyrimidine (98021-95-5) → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
With sodium methylate In acetonitrile; tert-butyl alcohol at 21 - 42℃; for 5.2h;	74.7%

Ethoxycarbonyl isothiocyanate (16182-04-0) + 2,5-dimethoxy-4-aminopyrimidine (6960-17-4) → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
Stage #1: Ethoxycarbonyl isothiocyanate; 4-amino-2,5-dimethoxypyrimidine In toluene at 27 - 87℃; Stage #2: In water; toluene at 40℃; Stage #3: With hydroxylamine In water; toluene at 68 - 81℃; pH=4.44 - 7.40; pH-value; Solvent; Temperature; Time; Reagent/catalyst;	70.4%

2,5-dimethoxy-4-cyanoaminopyrimidine (1578237-52-1) → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
Stage #1: 2,5-dimethoxy-4-cyanoaminopyrimidine With hydroxylamine hydrochloride; triethylamine In acetonitrile at 45℃; for 2h; Stage #2: With triethylamine; methyl chloroformate In acetonitrile at 5.8 - 76℃; for 4h;	52.8%
Multi-step reaction with 2 steps 1: hydroxylamine hydrochloride; triethylamine / methanol / 3 h / 45 °C 2: triethylamine; chloroformic acid ethyl ester / ethyl acetate; water / 12 h / 48 - 78 °C View Scheme

3-amino-8-methoxy-5-methylthio-1,2,4-triazolo[4,3-c]pyrimidine hydrobromide (219715-48-7) + sodium methylate (124-41-4) → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
With ethyl acrylate In methanol at 20℃; Cooling with ice;

2-chloro-5-methoxypyrimidin-4-amine (99979-77-8) → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
Multi-step reaction with 3 steps 1: ethyl acetate / 10 h / Reflux 2: hydroxylamine hydrochloride; sodium hydrogencarbonate / water; tert-butyl alcohol / 5 h / 20 °C 3: acetonitrile; methanol / 1.5 h / 20 °C View Scheme

Ethyl [(2-chloro-5-methoxypyrimidin-4-yl)amino]-carbonothioylcarbamate (1350919-10-6) → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: hydroxylamine hydrochloride; sodium hydrogencarbonate / water; tert-butyl alcohol / 5 h / 20 °C 2: acetonitrile; methanol / 1.5 h / 20 °C View Scheme

2,5-dimethoxy-4-aminopyrimidine (6960-17-4) → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
Multi-step reaction with 3 steps 1: ethyl acetate / 13.5 h / 78 °C 2: hydroxylamine hydrochloride; sodium hydroxide / ethyl acetate; water 3: ethyl acetate; water / 20 - 50 °C View Scheme

ethyl (E/Z)-[(2,5-dimethoxypyrimidin-4-yl)amino](hydroxyimino)methylcarbamate (1350919-14-0) → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
In water; ethyl acetate at 20 - 50℃;

4-chloro-2,5-dimethoxypyrimidine (370103-25-6) → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: 1-methyl-pyrrolidin-2-one / 2.5 h / 50 °C 2.1: hydroxylamine hydrochloride; triethylamine / acetonitrile / 2 h / 45 °C 2.2: 4 h / 5.8 - 76 °C View Scheme
Multi-step reaction with 3 steps 1: 1-methyl-pyrrolidin-2-one / 2.5 h / 50 °C 2: hydroxylamine hydrochloride; triethylamine / methanol / 3 h / 45 °C 3: triethylamine; chloroformic acid ethyl ester / ethyl acetate; water / 12 h / 48 - 78 °C View Scheme

2,5-dimethoxy-4-hydroxyguanidnylpyrimidine (1578237-53-2) → 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5)

Conditions	Yield
With chloroformic acid ethyl ester; triethylamine In water; ethyl acetate at 48 - 78℃; for 12h;

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + ethyl ((2-(dimethylcarbamoyl)phenyl)sulfonyl)carbamate → C17H19N7O6S

Conditions	Yield
In toluene at 90 - 100℃; under 225.023 - 300.03 Torr; for 6h;	98.1%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 2-bromo-6-trifluoromethybenzenesulfonyl chloride (1431291-88-1) → 2-bromo-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidine-2-yl)benzenesulfonamide (1431291-87-0)

Conditions	Yield
With 3,5-Lutidine; sulfilimine In acetonitrile at 45℃; for 24h;	92.7%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + C9H6F6O3S → penoxsulam

Conditions	Yield
With dmap In N,N-dimethyl-formamide at 60℃; for 6h; Reagent/catalyst;	91.7%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 2-(2',2'-difluoroethoxy)-6-trifluoromethylbenzene-1-sulfonyl chloride (865352-01-8) → penoxsulam

Conditions	Yield
With 3,5-Lutidine; dimethyl sulfoxide In 3,5-Lutidine at 20℃; for 8.5h; Product distribution / selectivity;	91%
With 3,5-Lutidine; dimethyl sulfoxide In acetonitrile at 20℃; for 24h; Product distribution / selectivity;	89%
With 3-Methylpyridine; N-(5,8-dimethoxy[1,2,4]triazolo[1,5-c]pyrimidin-2-yl)-S,S-dimethylsulfilimine hydrochloride In acetonitrile at 8 - 48℃; for 20 - 48h; Product distribution / selectivity;	86%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + o-Methoxybenzenesulfonyl chloride (10130-87-7) → 2-methoxy-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide (219713-00-5)

Conditions	Yield
With pyridine; dimethyl sulfoxide In acetonitrile for 6h;	90%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 2-methoxy-4-(trifluoromethyl)-pyridine-3-sulfonyl chloride (219715-41-0) → 2-methoxy-4-(trifluoromethyl)-N-(5,8-dimethoxy[1,2,4]-triazolo[1,5-c]pyrimidin-2-yl)pyridine-3-sulfonamide (219714-45-1)

Conditions	Yield
With 3,5-Lutidine; dimethyl sulfoxide at 20 - 52℃; Product distribution / selectivity;	88%
With 3,5-Lutidine; dimethyl sulfoxide In acetonitrile at 20 - 30℃; for 17h; Product distribution / selectivity;	85%
With pyridine; dimethyl sulfoxide In dichloromethane

2,6-dimethoxybenzenesulfonyl chloride (145980-89-8) + 2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) → 2,6-dimethoxy-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide (219713-28-7)

Conditions	Yield
With pyridine; dimethyl sulfoxide In acetonitrile for 6h;	68%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 2,6-dichlorobenzenesulfonyl chloride (6579-54-0) → 2,6-dichloro-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide (219713-14-1)

Conditions	Yield
With pyridine; dimethyl sulfoxide In acetonitrile for 6h;	63%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 2,5-dichlorobenzenesulphonyl chloride (5402-73-3) → 2,5-dichloro-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide (219714-11-1)

Conditions	Yield
With pyridine; dimethyl sulfoxide In acetonitrile for 6h;	62%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 2-(2',2'-difluoroethoxy)-6-trifluoromethylbenzene-1-sulfonyl chloride (865352-01-8) → 3-(2,2-difluoroethoxy)-N-(5,8-dimethoxy [1,2,4] triazolo[1,5-c]pyrimidin-2-yl)-cL,cL,cL-trifluorotoluene-2-sulfonamide

Conditions	Yield
With pyridine; dimethyl sulfoxide In acetonitrile Molecular sieve;	54%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 2-(2-fluoroethoxy)-6-trifluoromethylbenzenesulfonyl chloride (1176126-32-1) → 2-(2-fluoroethoxy)-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide (219714-72-4)

Conditions	Yield
With pyridine; dimethyl sulfoxide In acetonitrile for 6h;	52%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 3,5-dichlorobenzensulfonyl chloride (705-21-5) → 3,5-dichloro-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide (1138323-47-3)

Conditions	Yield
With pyridine; dimethyl sulfoxide In acetonitrile for 6h;	34%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 2-(2,2,2-trifluoroethoxy)-6-trifluoromethylbenzenesulfonyl chloride (1176126-33-2) → 2-(2,2,2-trifluoroethoxy)-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide (219714-91-7)

Conditions	Yield
With pyridine; dimethyl sulfoxide In acetonitrile for 6h;	30%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 2-(3-fluoropropoxy)-6-trifluoromethylbenzenesulfonyl chloride (1176126-35-4) → 2-(3-fluoropropoxy)-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide (1176126-22-9)

Conditions	Yield
With pyridine; dimethyl sulfoxide In acetonitrile for 6h;	30%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 2-ethoxy-6-trifluoromethylbenzenesulfonyl chloride (145980-85-4) → 2-ethoxy-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide (219713-46-9)

Conditions	Yield
With pyridine; dimethyl sulfoxide In acetonitrile for 6h;	29%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 2-methoxy-6-(trifluoromethyl)benzene-sulfonyl chloride (145980-58-1) → 2-methoxy-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide (219713-19-6)

Conditions	Yield
With pyridine; dimethyl sulfoxide In acetonitrile for 6h;	29%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 2-trifluoromethylbenzenesulfonyl chloride (776-04-5) → 2-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide (219712-99-9)

Conditions	Yield
With pyridine; dimethyl sulfoxide In acetonitrile for 6h;	20%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + 2-[2-fluoro-1-(fluoromethyl)ethoxy]-6-trifluoromethylbenzenesulfonyl chloride (1176126-34-3) → 2-[2-fluoro-1-(fluoromethyl)ethoxy]-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide (219714-93-9)

Conditions	Yield
With pyridine; dimethyl sulfoxide In acetonitrile for 6h;	19%

2-amino-5,8-dimethoxy[1,2,4]triazolo-[1,5-c]pyrimidine (219715-62-5) + dimethylsulfide (75-18-3) → N-(5,8-dimethoxy[1,2,4]triazolo[1,5-c]pyrimidin-2-yl)-S,S-dimethylsulfilimine hydrochloride

Conditions	Yield
With N-chloro-succinimide In dichloromethane; acetonitrile at -28 - 20℃; Product distribution / selectivity;
With 3-Methylpyridine; chlorine In acetonitrile at -25 - 8℃; Product distribution / selectivity;

Upstream product

• 219715-48-7 3-amino-8-methoxy-5-methylthio-1,2,4-triazolo[4,3-c]pyrimidine hydrobromide 
• 124-41-4 sodium methylate 
• 99979-77-8 2-chloro-5-methoxypyrimidin-4-amine 
• 1350919-12-8 5-chloro-8-methoxy[1,2,4]triazolo[1,5-c]pyrimidin-2-amine 
• 1350919-10-6 Ethyl [(2-chloro-5-methoxypyrimidin-4-yl)amino]-carbonothioylcarbamate 
• 6960-17-4 4-amino-2,5-dimethoxypyrimidine 
• 1350919-14-0 ethyl (E/Z)-[(2,5-dimethoxypyrimidin-4-yl)amino](hydroxyimino)methylcarbamate 
• 1350919-13-9 4-[4-(2,5-dimethoxypyrimidinyl)] 
• 1578237-52-1 2,5-dimethoxy-4-cyanoaminopyrimidine 
• 1578237-53-2 2,5-dimethoxy-4-hydroxyguanidnylpyrimidine 
• 370103-25-6 4-chloro-2,5-dimethoxypyrimidine 
• 16182-04-0 Ethoxycarbonyl isothiocyanate 
• 98021-95-5 2-Chloro-4-hydrazino-5-methoxy-pyrimidine 
• 506-68-3 bromocyane 

Downstream Products

• 219713-28-7 2,6-dimethoxy-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide 
• 219713-46-9 2-ethoxy-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide 
• 219713-19-6 2-methoxy-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide 
• 219714-72-4 2-(2-fluoroethoxy)-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide 
• 219714-91-7 2-(2,2,2-trifluoroethoxy)-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide 
• 219714-93-9 2-[2-fluoro-1-(fluoromethyl)ethoxy]-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide 
• 1176126-22-9 2-(3-fluoropropoxy)-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide 
• 1138323-47-3 3,5-dichloro-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide 
• 219713-14-1 2,6-dichloro-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide 
• 219713-00-5 2-methoxy-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide 
• 219714-11-1 2,5-dichloro-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide 
• 219712-99-9 2-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidin-2-yl)benzenesulfonamide 
• 1431291-87-0 2-bromo-6-trifluoromethyl-N-(5,8-dimethoxy-1,2,4-triazolo[1,5-c]pyrimidine-2-yl)benzenesulfonamide 
• 219714-96-2 penoxsulam 

Relevant articles and documents

2-amino -5,8-disubstituted [1, 2, 4] triazolo [1,5-c] pyrimidine method for synthesizing environmental protection

A disclosed environment-friendly synthetic method for 2-amino-5,8-disubstituted-[1,2,4]triazole[1,5-c]pyrimidine comprises performing thiocyanation reaction on a chloroformate and a thiocyanate to obtain a thiocyanatoformate of a formula III compound; performing condensation reaction on the thiocyanatoformate and a formula IV compound to obtain a formula V compound; and performing a ring-closure reaction on the formula V compound under the effect of a hydroxylamine salt and a sodium alkoxide to obtain a formula I compound. The method provided by the invention employing routine raw material, is low in production cost and suitable for industrialized production, is short in reaction route, mild in reaction conditions and easily-controllable in reaction process, and does not generate various high-pollution wastewater during synthesis and is in favor of environment protection. Additionally, the synthetic route is shown in the specification.

PROCESS FOR THE PREPARATION OF 2-AMINO-5,8-DIMETHOXY[1,2,4]TRIAZOLO[1,5-c]PYRIMIDINE FROM 4-CHLORO-2,5-DIMETHOXYPYRIMIDINE

2-Amino-5,8-dialkoxy[1,2,4]-triazolo[1,5-c]pyrimidines are manufactured from 4-chloro-2,5-dialkoxypyrimidines in a process that avoids hydrazine and cyanogen halide.

PROCESS FOR THE PREPARATION OF 5-SUBSTITUTED-8-ALKOXY[1,2,4]TRIAZOLO[1,5-c]PYRIMIDIN-2-AMINES

5-Substituted-8-alkoxy[1,2,4]triazolo[1,5-c]pyrimidin-2-amines are manufactured from 2-substituted-4-amino-5-methoxypyrimidines in a process that avoids hydrazine and cyanogen halide.