930-36-9

Basic information

• Product Name: 1-Methylpyrazole
• Synonyms: 1-METHYLPYRAZOLE;1-METHYL-1H-PYRAZOLE;AKOS PAO-1140;N-METHYLPYRAZOLE;TRIS-1-PYRAZOLYLMETHANE;1H-Pyrazole, 1-methyl-;methylpyrazole;Pyrazole, 1-methyl-
• CAS NO: 930-36-9
• Molecular Formula: C₄H₆N₂
• Molecular Weight: 82.1
• EINECS: -0
• Product Categories: Pyrazoles & Triazoles;Pyrazoles & Triazoles;Building Blocks;Heterocyclic Building Blocks;Pyrazoles
• Mol File: 930-36-9.mol
• Article Data: 28

Chemical Properties

• Melting Point: 36.5°C (estimate)
• Boiling Point: 127 °C
• Flash Point: 35 °C
• Appearance: Clear colorless to light yellow/Liquid
• Density: 0.988 g/mL at 20 °C(lit.)
• Vapor Pressure: 13.8mmHg at 25°C
• Refractive Index: n20/D 1.477
• Storage Temp.: Flammables area
• PKA: 2.25±0.10(Predicted)
• Water Solubility: Soluble in water
• BRN: 105207
• CAS DataBase Reference: 1-Methylpyrazole(CAS DataBase Reference)
• NIST Chemistry Reference: 1-Methylpyrazole(930-36-9)
• EPA Substance Registry System: 1-Methylpyrazole(930-36-9)

Safety Data

• Hazard Codes: Xi
• Statements: 10-36/37/38
• Safety Statements: 26-37/39-16
• RIDADR: UN 1993 3/PG 3
• WGK Germany: 3
• F: 10
• HazardClass: 3
• PackingGroup: III
• Hazardous Substances Data: 930-36-9(Hazardous Substances Data)

Usage

Chemical Properties

clear colorless to light yellow liquid

Definition

ChEBI: A member of the class of pyrazoles that is the 1-methyl derivative of 1H-pyrazole.

InChI:InChI=1/C4H6N2/c1-6-4-2-3-5-6/h2-4H,1H3

Synthetic route

NH-pyrazole (288-13-1) + methyl iodide (74-88-4) → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
With potassium hydroxide; tetrabutylammomium bromide at 0℃; for 6h;	90%
With potassium tert-butylate; 18-crown-6 ether In diethyl ether for 1h; Ambient temperature;	86%
With potassium hydroxide In water at 20 - 37℃;	85%

1-methyl-1H-pyrazole-5-carboxylic acid (16034-46-1) → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
In neat (no solvent) at 235 - 250℃;	81%

NH-pyrazole (288-13-1) + carbonic acid dimethyl ester (616-38-6) → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
at 140℃; for 8h; atmospheric pressure;	69%
at 115 - 140℃; for 8 - 9h;	14%

NH-pyrazole (288-13-1) + dimethyl sulfate (77-78-1) → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
With sodium hydroxide	60%
With sodium hydroxide; tetra(n-butyl)ammonium hydrogensulfate In dichloromethane; water at 20℃;	53%

1-methyl-5-(trimethylsilyl)-1H-pyrazole (92524-99-7) + butyraldehyde (123-72-8) → 1-methyl-1H-pyrazole (930-36-9) + 5-(1-hydroxybutyl)-1-methylpyrazole (92525-22-9)

Conditions	Yield
cesium fluoride In N,N-dimethyl-formamide at 50℃; for 1.33333h;	A 30% B 10%

NH-pyrazole (288-13-1) → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
With sodium hydroxide; dimethyl sulfate

4-bromo-1-methyl-1H-pyrazole (15803-02-8) + n-butyllithium (109-72-8, 29786-93-4) + diethyl ether (60-29-7) → 1-methyl-1H-pyrazole (930-36-9) + 1-methyl-1H-pyrazole-4-carboxylic acid (5952-92-1)

Conditions	Yield
anschl. mit CO2 bei -70grad;

malondialdehyde bis(diethyl acetal) (122-31-6) → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
With ethanol; methylhydrazine sulfuric acid

1,2-dimethyl-1H-pyrazol-2-ium iodide (26429-26-5) → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
bei der trocknen Destillation;

bis(pyrazol-1-yl)methane (27258-04-4) → NH-pyrazole (288-13-1) + 1-methyl-1H-pyrazole (930-36-9) + Tris(pyrazolyl)methane (80510-03-8)

Conditions	Yield
at 600 - 750℃; under 0.01 Torr;	A 25.2 % Chromat. B 10.0 % Chromat. C 30.8 % Chromat.
at 600 - 750℃; under 0.01 Torr;	A 25.2 % Chromat. B 10 % Chromat. C 30.8 % Chromat.

methyl iodide (74-88-4) + pyrazole silver → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
With diethyl ether at 120℃; im Rohr;

4-bromo-1-methyl-1H-pyrazole (15803-02-8) + diethyl ether (60-29-7) + phenyllithium (591-51-5) → 1-methyl-1H-pyrazole (930-36-9) + 1-methyl-1H-pyrazole-4-carboxylic acid (5952-92-1) + bromobenzene (108-86-1) + benzoic acid and 4-bromo-2-methyl-2H-pyrazole-3-carboxylic acid

Conditions	Yield
anschl. mit CO2 bei -70grad;

methylpropargylhydrazine (7422-82-4) → 1-methyl-1H-pyrazole (930-36-9) + methyl-propa-1,2-dienyl-diazene

Conditions	Yield
With manganese(IV) oxide In dichloromethane at 0℃;	A 21 % Spectr. B 65 % Spectr.

methyl-propa-1,2-dienyl-diazene → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
In benzene at 30℃;

pyridine (110-86-1) + 1-methylpyrazolidine (16460-04-1) → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
With hydrogen sulfide

methanol (67-56-1) + malonaldehydebis(dimethylacetal) (102-52-3) → NH-pyrazole (288-13-1) + 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
Stage #1: methanol With sulfuric acid; hydrazine hydrate at 0 - 25℃; Stage #2: malonaldehydebis(dimethylacetal) at 68 - 69℃; for 2h; Stage #3: With sodium hydroxide at 0 - 55℃;	A 82.2 %Chromat. B 16.4 %Chromat.

NH-pyrazole (288-13-1) + methylene chloride (74-87-3) → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
With sodium hydroxide In methanol at 50 - 55℃; under 1551.49 - 2585.81 Torr; for 6h;	16.4 %Chromat.

NH-pyrazole (288-13-1) + sodium methylate (124-41-4) → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
With carbonic acid dimethyl ester Reflux;

methyl 3-methoxyprop-2-enoate (34846-90-7) + methylhydrazine (60-34-4) → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
In methanol for 16h; Inert atmosphere; Reflux;

4-iodo-1-methyl-1H-pyrazole (39806-90-1) → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
With methanol; sodium tetrahydroborate; Pd/AlO(OH); water at 20℃; for 1.5h; Sonication; Schlenk technique;	> 95 %Chromat.

C4H6AuClN2 → 1-methyl-1H-pyrazole (930-36-9)

Conditions	Yield
In dimethyl sulfoxide

1-methyl-1H-pyrazole (930-36-9) → (1-methyl-1H-pyrazol-5-yl)boronic acid (720702-41-0)

Conditions	Yield
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In tetrahydrofuran at -78℃; for 1.5h; Stage #2: With Triisopropyl borate In tetrahydrofuran at -78 - 0℃; Stage #3: With hydrogenchloride; water In tetrahydrofuran pH=6;	100%
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In tetrahydrofuran; hexane at -78℃; Stage #2: With Triisopropyl borate In tetrahydrofuran; hexane at -78 - 0℃; Stage #3: With hydrogenchloride; water In tetrahydrofuran; hexane pH=6;	60%
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In tetrahydrofuran; hexane at 5 - 20℃; for 1h; Stage #2: With Trimethyl borate In tetrahydrofuran; hexane at -70℃; for 0.5h; Stage #3: With ammonium chloride In tetrahydrofuran; hexane at -15 - 20℃; for 1h;	38%
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 2h; Stage #2: With Triisopropyl borate In tetrahydrofuran; hexane at -78 - 20℃; Stage #3: With hydrogenchloride In water pH=6;

1-methyl-1H-pyrazole (930-36-9) + bromoacetic acid methyl ester (96-32-2) → 4-(2-methoxy-2-oxoethyl)-1-methyl-1H-1,2,4-triazol-4-ium bromide

Conditions	Yield
for 72h;	100%

1-methyl-1H-pyrazole (930-36-9) → 4-iodo-1-methyl-1H-pyrazole (39806-90-1)

Conditions	Yield
With iodine; iodic acid In tetrachloromethane; water; acetic acid at 50℃; for 1.5h;	99%
With dihydrogen peroxide; iodine In water at 20℃; for 24h;	91%
Stage #1: 1-methyl-1H-pyrazole With iodine for 0.166667h; Large scale; Stage #2: With dihydrogen peroxide at 18 - 20℃; for 42.5h; Large scale;	91%

1-methyl-1H-pyrazole (930-36-9) + [(norbornadiene)RhCl]2 → Rh(1+)*Cl(1-)*C7H8*C3H3N2(CH3)*0.25CH2Cl2=[RhCl(C7H8)(C3H3N2(CH3))]*0.25CH2Cl2

Conditions	Yield
With CH2Cl2 In dichloromethane inert atmosphere; stirring (25°C, 2 h); solvent redn. (vac.), pptn. on hexane addn., filtn., washing (hexane), drying (vac.); elem. anal.;	99%

1-methyl-1H-pyrazole (930-36-9) + rhodium (II) octanoate dimer (73482-96-9) → [Rh2(octanoato)4(1-methylpyrazole)] (1268445-96-0)

Conditions	Yield
In chloroform (N2); a soln. of ligand added to Rh complex in CHCl3, stirred at room temp. for 1 h; evapd. (vac.); elem. anal.;	99%

1-methyl-1H-pyrazole (930-36-9) + rhodium (II) octanoate dimer (73482-96-9) → [Rh2(octanoato)4(1-methylpyrazole)2] (1268445-97-1)

Conditions	Yield
In chloroform (N2); a soln. of ligand added to Rh complex in CHCl3, stirred at room temp. for 1 h; evapd. (vac.); elem. anal.;	99%

1-methyl-1H-pyrazole (930-36-9) → 1-methyl-3-nitro-1H-pyrazole (54210-32-1)

Conditions	Yield
With silica-sulfuric acid impregnated with bismuth nitrate In tetrahydrofuran at 20℃; for 6h; Reagent/catalyst; Green chemistry;	98%

1-methyl-1H-pyrazole (930-36-9) + 4-Octyne (1942-45-6) → C12H20N2

Conditions	Yield
With bis(acetylacetonate)nickel(II); trimethylaluminum In hexane; toluene at 35℃; for 12h;	96%

1-methyl-1H-pyrazole (930-36-9) → 1-methyl-3,4-dinitropyrazole (66296-67-1)

Conditions	Yield
With bismuth(III) nitrate In tetrahydrofuran at 20℃; for 12h;	96%
With silica-sulfuric acid impregnated with bismuth nitrate In tetrahydrofuran at 20℃; for 6h; Reagent/catalyst; Green chemistry;	92%

1-methyl-1H-pyrazole (930-36-9) + di(rhodium)tetracarbonyl dichloride → cis-chloro(dicarbonyl)(1-methylpyrazole)rhodium(I) (1392329-57-5)

Conditions	Yield
In dichloromethane at 20℃; for 6h; Inert atmosphere;	96%

1-methyl-1H-pyrazole (930-36-9) + Fe(CO)2[o-{η2-(H-SiMe)2}C6H4][o-(SiMe)2C6H4] → Fe(Me2SiC6H4SiMe2)(1-methylpyrazole)2(CO)2

Conditions	Yield
In tetrahydrofuran at 20℃; for 1h; Schlenk technique;	96%

1-methyl-1H-pyrazole (930-36-9) + 1-methyl-4-((phenylethynyl)sulfonyl)benzene (28995-88-2) → 1-methyl-5-(phenylethynyl)-1H-pyrazole

Conditions	Yield
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In diethyl ether; hexane at 0℃; Stage #2: 1-methyl-4-((phenylethynyl)sulfonyl)benzene In diethyl ether for 0.25h; Inert atmosphere;	96%

1-methyl-1H-pyrazole (930-36-9) + 2,3,5,6-tetrafluoropyridine (2875-18-5) → C9H5F4N3

Conditions	Yield
With chloro(dimethylsulfide) gold(I); silver(I) acetate; I,I-bis(acetoxy)iodobenzene In 1,4-dioxane at 100℃; for 15h; Inert atmosphere; regioselective reaction;	96%

1-methyl-1H-pyrazole (930-36-9) + (4-bromo-6-formyl-benzothiazol-2-yl)-carbamic Acid tert-butyl Ester (1155287-20-9) → {4-Bromo-6-[hydroxy-(2-methyl-2H-pyrazol-3-yl)-methyl]-benzothiazol-2-yl}-carbamic Acid tert-butyl Ester (1155287-24-3)

Conditions	Yield
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In tetrahydrofuran; methanol; hexane at -78 - 20℃; for 1.5h; Stage #2: (4-bromo-6-formyl-benzothiazol-2-yl)-carbamic Acid tert-butyl Ester In tetrahydrofuran; hexane at -58 - 20℃; for 2h; Stage #3: With ammonium chloride In tetrahydrofuran; hexane; water	95%

1-methyl-1H-pyrazole (930-36-9) + N,N-diethylacrylamide (2675-94-7) → (E)-N,N-diethyl-3-(1-methyl-1H-pyrazol-4-yl)acrylamide

Conditions	Yield
With 4,5-Diazafluoren-9-one; oxygen; palladium diacetate; trifluoroacetic acid; p-benzoquinone In 1,4-dioxane at 100℃; under 760.051 Torr; for 24h; regioselective reaction;	95%

1-methyl-1H-pyrazole (930-36-9) + 2-bromoethylamine hydrobromide (2576-47-8) → 2-(2-aminoethyl)-1-methyl-1H-pyrazol-2-ium bromide hydrobromide

Conditions	Yield
In ethanol at 80℃; for 72h;	94.3%

1-methyl-1H-pyrazole (930-36-9) + dimethyldimethoxysilan (1112-39-6) + Nonafluorobutanesulfonyl fluoride (375-72-4) → N,N-dimethylimidazoliumperfluorobutylsulfonate + dimethyldifluorosilane (353-66-2)

Conditions	Yield
In diethyl ether 35°C , 24 h;	A 94% B n/a
In diethyl ether 35°C , 24 h;	A 94% B n/a

1-methyl-1H-pyrazole (930-36-9) + [Rh(CO)2(μ-I)]2 → cis-iodo(dicarbonyl)(1-methylpyrazole)rhodium(I) (1392329-62-2)

Conditions	Yield
In dichloromethane at -10.16 - 20℃; Inert atmosphere;	94%

1-methyl-1H-pyrazole (930-36-9) + 3-bromopropylamine hydrochloride (5003-71-4) → 2-(3-aminopropyl)-1-methyl-1H-pyrazol-2-ium bromide hydrobromide

Conditions	Yield
In ethanol at 80℃; for 72h;	93.2%

1-methyl-1H-pyrazole (930-36-9) + Triisopropyl borate (5419-55-6) → (1-methyl-1H-pyrazol-5-yl)boronic acid (720702-41-0)

Conditions	Yield
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In tetrahydrofuran at -78℃; for 1.5h; Stage #2: Triisopropyl borate In tetrahydrofuran at 20℃;	93%
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In tetrahydrofuran; hexanes at -78℃; for 0.5h; Stage #2: Triisopropyl borate In tetrahydrofuran; hexanes at -78 - 0℃; for 1h; Stage #3: With hydrogenchloride In tetrahydrofuran; hexanes; water for 1h;

1-methyl-1H-pyrazole (930-36-9) + 4-fluorobenzaldehyde (459-57-4) → (4-fluorophenyl)(1-methyl-1H-pyrazol-5-yl)methanol (1020712-91-7)

Conditions	Yield
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In tetrahydrofuran at -78℃; for 0.0833333h; Stage #2: 4-fluorobenzaldehyde In tetrahydrofuran at -78 - 20℃; for 1h; Stage #3: With ammonium chloride In water	93%

1-methyl-1H-pyrazole (930-36-9) + Trimethyl borate (121-43-7) → (1-methyl-1H-pyrazol-5-yl)boronic acid (720702-41-0)

Conditions	Yield
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In tetrahydrofuran; hexane at 0 - 20℃; for 4h; Stage #2: Trimethyl borate In tetrahydrofuran; hexane at -70℃;	93%

1-methyl-1H-pyrazole (930-36-9) → 1-methylpyrazole hydrobromide

Conditions	Yield
With hydrogen bromide	93%

1-methyl-1H-pyrazole (930-36-9) → 5-iodo-1-methyl-1H-pyrazole (34091-51-5)

Conditions	Yield
Stage #1: 1-methyl-1H-pyrazole With (PMDETA)2K2Mg(CH2SiMe3)4 at 0℃; for 2h; Inert atmosphere; Schlenk technique; Stage #2: With iodine for 1h; Inert atmosphere; Schlenk technique; regioselective reaction;	92%
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 1.25h; Stage #2: With iodine In tetrahydrofuran at 20℃; for 1h;	90%
Stage #1: 1-methyl-1H-pyrazole With (THF)Li(TMP)Zn(tBu)2 In tetrahydrofuran at 25℃; for 1h; Inert atmosphere; Stage #2: With iodine In tetrahydrofuran at 25℃; for 1h; Inert atmosphere; regioselective reaction;	89%

1-methyl-1H-pyrazole (930-36-9) + palladium dichloride + 1,3-bis[2,6-diisopropylphenyl]imidazolium chloride (250285-32-6) → C31H42Cl2N4Pd

Conditions	Yield
With potassium carbonate In tetrahydrofuran at 80℃; for 18h; Inert atmosphere; Sealed tube;	91%

1-methyl-1H-pyrazole (930-36-9) → 5-bromo-1-methyl-1H-pyrazole

Conditions	Yield
With ferric(III) bromide; bromine In tert-butyl methyl ether at 0 - 20℃;	90.5%
With n-butyllithium; bromine In tetrahydrofuran at -76 - -70℃; Inert atmosphere;	47.5%

1-methyl-1H-pyrazole (930-36-9) → 5-Chloro-1-methylpyrazole (42110-76-9)

Conditions	Yield
With aluminum (III) chloride; chlorine In tert-butyl methyl ether at 0 - 20℃;	90.5%

1-methyl-1H-pyrazole (930-36-9) + N,N-dimethyl-formamide (68-12-2, 33513-42-7) → 1-methyl-1H-pyrazole-5-carbaldehyde (27258-33-9)

Conditions	Yield
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In tetrahydrofuran; hexane at -20℃; for 2.5h; Stage #2: N,N-dimethyl-formamide In tetrahydrofuran; hexane at -20℃; for 1h;	90%
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In tetrahydrofuran; hexane at -20℃; for 2.5h; Stage #2: N,N-dimethyl-formamide In tetrahydrofuran; hexane at -20℃; for 1h;	90%
Stage #1: 1-methyl-1H-pyrazole With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 1h; Inert atmosphere; Stage #2: N,N-dimethyl-formamide In tetrahydrofuran; hexane for 1h; Inert atmosphere;	58%

1-methyl-1H-pyrazole (930-36-9) + 4,4,5,5-tetramethyl-[1,3,2]-dioxaboralane (25015-63-8) → 1-methyl-5-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-1H-pyrazole (847818-74-0)

Conditions	Yield
Stage #1: 4,4,5,5-tetramethyl-[1,3,2]-dioxaboralane With C26H50CoN4O2 at 20℃; for 0.0833333h; Inert atmosphere; Glovebox; Stage #2: 1-methyl-1H-pyrazole at 80℃; for 48h; Inert atmosphere; Sealed tube;	90%

Upstream product

• 288-13-1 NH-pyrazole 
• 74-88-4 methyl iodide 
• 122-31-6 malondialdehyde bis(diethyl acetal) 
• 15803-02-8 4-bromo-1-methyl-1H-pyrazole 
• 60-29-7 diethyl ether 
• 591-51-5 phenyllithium 
• 616-38-6 carbonic acid dimethyl ester 
• 124-41-4 sodium methylate 
• 847818-74-0 1-methyl-5-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-1H-pyrazole 
• 39806-90-1 4-iodo-1-methyl-1H-pyrazole 
• 34846-90-7 methyl 3-methoxyprop-2-enoate 
• 60-34-4 methylhydrazine 
• 74-87-3 methylene chloride 
• 67-56-1 methanol 

Downstream Products

• 16034-46-1 1-methyl-1H-pyrazole-5-carboxylic acid 
• 15803-02-8 4-bromo-1-methyl-1H-pyrazole 
• 93331-04-5 (2-methyl-2H-pyrazol-3-yl)-diphenyl-methanol 
• 39806-90-1 4-iodo-1-methyl-1H-pyrazole 
• 34091-53-7 3,4-diiodo-1-methylpyrazole 
• 87581-71-3 (p-methylphenyl)-bis(1-methylpyrazol-5'-yl)carbinol 
• 133797-82-7 1-(1H-benzimidazol-2-yl)-2-methyl-pyrazolium chloride 
• 6488-88-6 2--benzimidazol 
• 92525-04-7 1-<(trimethylsilyl)methyl>pyrazole 
• 92524-99-7 1-methyl-5-(trimethylsilyl)-1H-pyrazole 
• 87581-70-2 1-methyl-5-<1'-hydroxy-1'-(p-methylphenyl)>pyrazole 
• 32500-66-6 1-<(2'-hydroxy-2'-phenylethyl)>pyrazole 
• 32500-65-5 1-methyl-5-(1'-hydroxy-1'phenylmethyl)pyrazole 
• 121704-47-0 1-Methyl-2-(2-oxo-2-p-tolyl-ethyl)-2H-pyrazol-1-ium; bromide 

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