637-60-5

Basic information

• Product Name: 4-Methylphenylhydrazine hydrochloride
• Synonyms: P-Tolylhydrozine hydrochloride;p-tolylhydrazine HCl salt;p-Tolylhydrazine hydrochloride ,97%;p-Tolylhydrazine hydrochloride, 98% 25GR;p-Tolylhydrazine hydrochloride, 4-Hydrazinotoluene hydrochloride;4-Tolylhydrazine Monohydrochloride;Fortoluenehydrazine hydrochloride;Hydrazine,(4-Methylphenyl)-, hydrochloride (1:1)
• CAS NO: 637-60-5
• Molecular Formula: C₇H₁₁N₂*Cl
• Molecular Weight: 158.63
• EINECS: 211-295-2
• Product Categories: Aromatic Hydrazides, Hydrazines, Hydrazones and Oximes;Phenylhydrazine;Building Blocks;Chemical Synthesis;Hydrazines;Nitrogen Compounds;Organic Building Blocks
• Mol File: 637-60-5.mol
• Article Data: 28

Chemical Properties

• Melting Point: >200 °C (dec.)(lit.)
• Boiling Point: 217.6°C (rough estimate)
• Flash Point: 115.3 °C
• Appearance: Off-white to beige-brownish/Flaky Powder
• Density: 0.9532 (rough estimate)
• Refractive Index: 1.6230 (estimate)
• Storage Temp.: Store below +30°C.
• Solubility: DMSO, Methanol
• Water Solubility: soluble
• Merck: 14,9542
• BRN: 3563996
• CAS DataBase Reference: 4-Methylphenylhydrazine hydrochloride(CAS DataBase Reference)
• NIST Chemistry Reference: 4-Methylphenylhydrazine hydrochloride(637-60-5)
• EPA Substance Registry System: 4-Methylphenylhydrazine hydrochloride(637-60-5)

Safety Data

• Hazard Codes: Xn,Xi
• Statements: 22-36/37/38-40
• Safety Statements: 26-36-36/37/39
• RIDADR: UN 2811 6.1/PG 3
• WGK Germany: 3
• RTECS: MW0195000
• TSCA: Yes
• HazardClass: 6.1
• PackingGroup: III
• Hazardous Substances Data: 637-60-5(Hazardous Substances Data)

Usage

Chemical Properties

off-white to beige-brownish flaky powder

Uses

Different sources of media describe the Uses of 637-60-5 differently. You can refer to the following data:
1. 4-Tolylhydrazine Monohydrochloride has shown tumorigenic potential through studies. In addition, due to its hydrazine moiety, it has anti-cancer potential and is a compound from which derivatives are made in the search of novel anticancer drugs.
2. 4-Tolylhydrazine Monohydrochloride has shown tumorigenic potential through studies. In addition, due to its hydrazine moiety, it has anti-cancer potential and is a compound from which derivatives are made in the search of novel anticancer drugs.

InChI:InChI=1/C7H10N2.ClH/c1-6-2-4-7(9-8)5-3-6;/h2-5,9H,8H2,1H3;1H

Synthetic route

N-(4-methylphenyl) benzophenone hydrazone (40594-88-5) → p-tolylhydrazine hydrochloride (637-60-5)

Conditions	Yield
With hydrogenchloride In ethanol; water at 20℃; for 24h; Inert atmosphere; Industrial scale;	100%
With hydrogenchloride In water at 20℃;	48%

p-toluidine (106-49-0) → p-tolylhydrazine hydrochloride (637-60-5)

Conditions	Yield
Stage #1: p-toluidine With hydrogenchloride; sodium nitrite In water for 1h; Stage #2: With sodium sulfite In water at 80℃; for 0.1h; Stage #3: With hydrogenchloride In water at 20 - 95℃;	90%
Stage #1: p-toluidine With hydrogenchloride; sodium nitrite In water at 0 - 5℃; Stage #2: With tin(ll) chloride In water at 5℃;	63%
Stage #1: p-toluidine With hydrogenchloride; sodium nitrite Stage #2: With hydrogenchloride; tin(ll) chloride

4-tolyl iodide (624-31-7) → p-tolylhydrazine hydrochloride (637-60-5)

Conditions	Yield
Stage #1: 4-tolyl iodide With potassium phosphate; copper(l) iodide; N,N′-bis(2,6-dimethylphenyl)oxalamide; cetyltrimethylammonim bromide In water at 80℃; for 0.25h; Schlenk technique; Inert atmosphere; Sealed tube; Stage #2: With hydrazine hydrate In water at 80℃; Inert atmosphere; Schlenk technique; Sealed tube; Stage #3: With hydrogenchloride In water pH=3 - 4; Inert atmosphere; Schlenk technique; Sealed tube;	85%
Multi-step reaction with 2 steps 1: bis(triphenylphosphine)nickel(II) chloride; 1,3-bis[2,6-diisopropylphenyl]imidazolium chloride; sodium t-butanolate / 1,4-dioxane / 5 h / 50 °C / Inert atmosphere 2: hydrogenchloride / water / 20 °C View Scheme

para-bromotoluene (106-38-7) → p-tolylhydrazine hydrochloride (637-60-5)

Conditions	Yield
Stage #1: para-bromotoluene With potassium phosphate; copper(l) iodide; N,N′-bis(2,6-dimethylphenyl)oxalamide; cetyltrimethylammonim bromide In water at 80℃; for 0.25h; Schlenk technique; Inert atmosphere; Sealed tube; Stage #2: With hydrazine hydrate In water at 80℃; for 7h; Inert atmosphere; Schlenk technique; Sealed tube; Stage #3: With hydrogenchloride In water pH=3 - 4; Catalytic behavior; Reagent/catalyst; Inert atmosphere; Schlenk technique; Sealed tube;	83%
Stage #1: para-bromotoluene With potassium phosphate; N,N'-bis(2,5-dimethylpyrrol-1-yl)oxalamide; cetyltrimethylammonim bromide; copper(I) bromide In water at 80℃; for 0.166667h; Sealed tube; Inert atmosphere; Stage #2: With hydrazine hydrate In water at 80℃; for 2h; Sealed tube; Inert atmosphere; Stage #3: With hydrogenchloride In dichloromethane; water Temperature;	70%
Multi-step reaction with 2 steps 1: bis(triphenylphosphine)nickel(II) chloride; 1,3-bis[2,6-diisopropylphenyl]imidazolium chloride; sodium t-butanolate / 1,4-dioxane / 5 h / 50 °C / Inert atmosphere 2: hydrogenchloride / water / 20 °C View Scheme

3-(4-methylphenyl)sydnone (3483-19-0) → p-tolylhydrazine hydrochloride (637-60-5)

Conditions	Yield
With hydrogenchloride In ethyl acetate at 60℃; for 0.25h; Ring cleavage;	76%

N-4-methylphenylhydrazine (539-44-6) → p-tolylhydrazine hydrochloride (637-60-5)

Conditions	Yield
With hydrogenchloride In water at 65℃;	39.3%

triphenyl-(N'-p-tolyl-hydrazino)-phosphonium; chloride → p-tolylhydrazine hydrochloride (637-60-5)

Conditions	Yield
With hydrogenchloride

ethanol (64-17-5) + 4-chloro-3-(4-tolyl)sydnone (3815-76-7) → p-tolylhydrazine hydrochloride (637-60-5) + ethyl 4-methylphenylhydrazinecarboxylate hydrochloride

Conditions	Yield
With hydrogenchloride

para-chlorotoluene (106-43-4) → p-tolylhydrazine hydrochloride (637-60-5)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: 2-(dicyclohexylphosphino)-2'-methylbiphenyl; sodium hydroxide; palladium diacetate / tert-Amyl alcohol / Inert atmosphere; Reflux; Industrial scale 1.2: Reflux; Inert atmosphere; Industrial scale 2.1: hydrogenchloride / ethanol; water / 24 h / 20 °C / Inert atmosphere; Industrial scale View Scheme

N-Nitroso-p-methylanilin (89693-79-8) → p-tolylhydrazine hydrochloride (637-60-5)

Conditions	Yield
With hydrogenchloride; tin(ll) chloride In water at 0℃;

p-tolylhydrazine hydrochloride (637-60-5) + 4-tercbutyl-cyclohexanone (98-53-3) → 3-(tert-butyl)-6-methyl-2,3,4,9-tetrahydrocarbazole

Conditions	Yield
at 250℃; for 0.0166667h; Fischer indole synthesis;	100%
With silica gel at 20℃; for 5h; Fischer Indole Synthesis; Milling;	64%

p-tolylhydrazine hydrochloride (637-60-5) + cyclopentanone (120-92-3) → 7-methyl-1,2,3,4-tetrahydrocyclopenta[b]indole (1130-93-4)

Conditions	Yield
at 250℃; for 0.0166667h; Fischer indole synthesis;	100%

p-tolylhydrazine hydrochloride (637-60-5) + pentan-3-one (96-22-0) → 2-ethyl-3,5-dimethyl-1H-indole (73177-34-1)

Conditions	Yield
at 250℃; for 0.0166667h; Fischer indole synthesis;	100%

p-tolylhydrazine hydrochloride (637-60-5) + 1,3-Diphenylpropanone (102-04-5) → 2-benzyl-5-methyl-3-phenyl-1H-indole

Conditions	Yield
at 250℃; for 0.0166667h; Fischer indole synthesis;	100%

trimethylacetylacetonitrile (59997-51-2) + p-tolylhydrazine hydrochloride (637-60-5) → 3-tert-butyl-1-p-tolyl-1H-pyrazol-5-amine (285984-25-0)

Conditions	Yield
In methanol	99%
With hydrogenchloride In ethanol for 48h; Reflux;	86%
With hydrogenchloride In ethanol at 80℃; for 8h;	86.4%

p-tolylhydrazine hydrochloride (637-60-5) + (E)-5-(2-Dimethylamino-vinyl)-1-phenyl-1H-tetrazol (125037-37-8) → N-[2-(1-Phenyl-1H-tetrazol-5-yl)-eth-(E)-ylidene]-N'-p-tolyl-hydrazine

Conditions	Yield
With water; acetic acid In methanol for 0.0833333h; Heating;	98%

cyclotridecanone (832-10-0) + p-tolylhydrazine hydrochloride (637-60-5) → 16-methyl-20-aza-tricyclo[11.7.0.014,19]eicosa-1(13),14(19),15,17-tetraene

Conditions	Yield
at 250℃; for 0.0166667h; Fischer indole synthesis;	98%

trimethylacetylacetonitrile (59997-51-2) + p-tolylhydrazine hydrochloride (637-60-5) → 3-amino-5-tert-butyl-2-(p-tolyl)-2H-pyrazole hydrochloride

Conditions	Yield
In methanol at 120℃; for 1h; microwave irradiation;	98%
In methanol Inert atmosphere; Reflux;	94%
In methanol for 16h; Reflux;	86%

4-neopentylcyclohexanone (606490-76-0) + p-tolylhydrazine hydrochloride (637-60-5) → 3-(2,2-dimethylpropyl)-6-methyl-2,3,4,9-tetrahydro-1H-carbazole (1456718-42-5)

Conditions	Yield
With 1,3,5-trichloro-2,4,6-triazine In ethanol at 80℃; for 2h; Fischer Indole Synthesis;	98%

p-tolylhydrazine hydrochloride (637-60-5) + 3,4-dihydronaphthalene-1(2H)-one (529-34-0) → 8-methyl-6,11-dihydro-5H-benzo[a]carbazole (50823-82-0)

Conditions	Yield
With toluene-4-sulfonic acid for 0.0833333h; Fischer indole synthesis; Microwave irradiation; neat (no solvent);	97%
at 250℃; for 0.0166667h; Fischer indole synthesis;	90%

p-tolylhydrazine hydrochloride (637-60-5) + cycloheptanone (502-42-1) → 2-methyl-5,6,7,8,9,10-hexahydrocyclohepta[b]indole (17897-01-7)

Conditions	Yield
at 250℃; for 0.0166667h; Fischer indole synthesis;	96%

3,4-dihydro-2H-pyran (110-87-2) + p-tolylhydrazine hydrochloride (637-60-5) → 3-(5-methyl-1H-indol-3-yl)propan-1-ol (29957-88-8)

Conditions	Yield
With acetic acid In water at 20 - 100℃; for 0.95h; Fischer indole synthesis;	96%
With sulfuric acid In N,N-dimethyl acetamide at 100℃; for 2h; Fischer indole reaction;	95%
With antimony(III) sulfate In methanol for 0.75h; Fischer indole synthesis; Reflux;	92%

ethyl 5-oxohexanoate (13984-57-1) + p-tolylhydrazine hydrochloride (637-60-5) → ethyl 3-(2,5-dimethylindol-3-yl)propionate

Conditions	Yield
Stage #1: ethyl 5-oxohexanoate; p-tolylhydrazine hydrochloride Stage #2: In toluene	96%

p-tolylhydrazine hydrochloride (637-60-5) + chloroformic acid ethyl ester (541-41-3) → ethyl 2-(4-methylphenyl)hydrazinecarboxylate (40887-65-8)

Conditions	Yield
With pyridine In acetonitrile at 0 - 20℃;	96%
With pyridine In acetonitrile at 0 - 20℃; for 1h;

p-tolylhydrazine hydrochloride (637-60-5) + propionaldehyde (123-38-6) → 6-methyl-2,3,4,9-tetrahydro-1H-carbazole (17177-17-2)

Conditions	Yield
With 4-methylbenzenesulfonic acid-based ionic liquid supported on silica gel In ethanol at 20℃; for 4h; Fischer Indole Synthesis;	96%

p-tolylhydrazine hydrochloride (637-60-5) + allylisocyanate (1476-23-9) → C11H15N3O

Conditions	Yield
With triethylamine In tetrahydrofuran at 20℃; for 7h;	96%

ethyl 2-(1H-indol-3-yl)-2-oxoacetate (51079-10-8) + p-tolylhydrazine hydrochloride (637-60-5) → 2-(4-methylphenyl)pyrazolo[3,4-c]quinolin-4(5H)-one (204511-52-4)

Conditions	Yield
With acetic acid In ethanol at 140℃; for 0.05h; microwave irradiation;	95%
With acetic acid In ethanol for 3h; Heating;	90%

p-tolylhydrazine hydrochloride (637-60-5) + Cyclohexyl methyl ketone (823-76-7) → 2',5'-dimethylspiro[cyclohexane-1,3'-indole] (468774-80-3)

Conditions	Yield
Stage #1: p-tolylhydrazine hydrochloride; Cyclohexyl methyl ketone With perchloric acid In ethanol for 2h; Heating; Stage #2: With sodium hydroxide at 20℃;	95%

methanol (67-56-1) + N-(4-methoxy benzylidene)-4-methoxyaniline (1749-08-2) + p-tolylhydrazine hydrochloride (637-60-5) + 4-Carboxybenzaldehyde (619-66-9) → 4-[1-(2,6-dichloro-4-methyl-phenyl)-4,5-bis-(4-methoxy-phenyl)-4,5-dihydro-1H-[1,2,4]triazol-3-yl]-benzoic acid methyl ester

Conditions	Yield
Multistep reaction;	95%

p-tolylhydrazine hydrochloride (637-60-5) + (+)-usnic acid (15853-98-2, 17669-01-1, 56190-51-3, 7562-61-0) → (S)-8-acetyl-5,7-dihydroxy-3,4a,6-trimethyl-1-(p-tolyl)-1,4a-dihydro-4H-benzofuro[3,2-f]indazol-4-one

Conditions	Yield
With pyridine In ethanol for 2h; Reflux;	95%

p-tolylhydrazine hydrochloride (637-60-5) + 1-methylcyclohexan-4-one (589-92-4) → 3,6-dimethyl-2,3,4,9-tetrahydro-1H-carbazole (70473-88-0)

Conditions	Yield
With acetic acid for 8h; Reflux;	95%
With acetic acid at 80℃; for 0.5h; Borsche reaction; Inert atmosphere;	93%
With silica gel at 20℃; for 4h; Fischer Indole Synthesis; Milling;	69%
With sodium acetate In acetic acid at 90℃; Reflux;	66%

16-dehydropregnenolone (1162-53-4) + p-tolylhydrazine hydrochloride (637-60-5) → (3S,16R,17S)-3'-methyl-1'-(4")-tolyl-2'-pyrazolino[4',5':17,16]androst-5-en-3-ol

Conditions	Yield
With toluene-4-sulfonic acid In ethanol at 100℃; for 0.333333h; Microwave irradiation; stereoselective reaction;	95%

p-tolylhydrazine hydrochloride (637-60-5) + benzalacetophenone (94-41-7) → 1-(4-methylphenyl)-3,5-diphenyl-1H-pyrazole (51390-16-0)

Conditions	Yield
With iodine In ethanol for 1h; Reflux; Inert atmosphere; Green chemistry; regioselective reaction;	95%

3-methoxy-19-norpregna-1,3,5(10),16-tetraene-20-one (21321-91-5) + p-tolylhydrazine hydrochloride (637-60-5) → (16R,17S)-3-methoxy-3′-methyl-1′-(4″-tolyl)-2′-pyrazolino[4′,5′:17,16]estra-1,3,5(10)-triene

Conditions	Yield
With toluene-4-sulfonic acid In ethanol at 100℃; for 0.333333h; Microwave irradiation;	95%

p-tolylhydrazine hydrochloride (637-60-5) → di(p-tolyl) disulfide (103-19-5)

Conditions	Yield
With sulfur; oxygen; cesium fluoride In water; toluene at 100℃; under 750.075 Torr; for 6h; Sealed tube; Schlenk technique;	95%

3-methyl-butan-2-one (563-80-4) + p-tolylhydrazine hydrochloride (637-60-5) → 2,3,3,5-tetramethyl-3H-indole (25981-82-2)

Conditions	Yield
In acetic acid for 3h; Reflux;	94%
With perchloric acid In ethanol Fischer indolization; Heating;	89%
With potassium acetate In acetic acid at 20℃; for 1.5h; Reflux;	79.5%

p-tolylhydrazine hydrochloride (637-60-5) + cyclohexanone (108-94-1) → 6-methyl-2,3,4,9-tetrahydro-1H-carbazole (17177-17-2)

Conditions	Yield
at 250℃; for 0.0166667h; Fischer indole synthesis;	94%
With silica gel at 20℃; for 3h; Fischer Indole Synthesis; Milling;	94%
With toluene-4-sulfonic acid for 0.0833333h; Fischer indole synthesis; Microwave irradiation; neat (no solvent);	93%

p-tolylhydrazine hydrochloride (637-60-5) + 3β-hydroxy-21-hydroxymethylidenepregn-5-en-20-one (196711-46-3) → 17β-(1-p-tolyl-3-pyrazolyl)androst-5-en-3β-ol (1233764-92-5)

Conditions	Yield
With boron trifluoride diethyl etherate In dichloromethane for 6h;	94%

methyl-3-pyridylketone (350-03-8) + p-tolylhydrazine hydrochloride (637-60-5) → 1-(pyridine-3-yl)ethan-1-one N-tosylhydrazone (1258795-07-1)

Conditions	Yield
With sodium acetate In ethanol at 80℃; for 0.0833333h; Microwave irradiation; air-cooling;	94%

Upstream product

• 3483-19-0 3-(4-methylphenyl)sydnone 
• 106-43-4 para-chlorotoluene 
• 40594-88-5 N-(4-methylphenyl) benzophenone hydrazone 
• 89693-79-8 N-Nitroso-p-methylanilin 
• 539-44-6 N-4-methylphenylhydrazine 
• 624-31-7 4-tolyl iodide 
• 106-38-7 para-bromotoluene 
• 106-49-0 p-toluidine 
• 64-17-5 ethanol 
• 3815-76-7 4-chloro-3-(4-tolyl)sydnone 

Downstream Products

• 107521-82-4 7-chloro-4-methyl-5-nitro-2-p-tolyl-2H-benzotriazole 
• 89314-29-4 2-p-tolylhydrazono-propionic acid 
• 67420-35-3 4-[(3-methyl-5-oxo-1-p-tolyl-1,5-dihydro-pyrazol-4-ylidene)-hydrazino]-N-thiazol-2-yl-benzenesulfonamide 
• 121597-18-0 3--acrolein-(p-tolylhydrazon) 
• 110570-04-2 4-Hydroxy-3-[1-(p-tolyl-hydrazono)-ethyl]-chromen-2-one 
• 79762-67-7 glyoxal-bis-p-tolylhydrazone 
• 75815-82-6 2-(2-(p-tolyl)hydrazono)acetaldehyde 
• 22120-39-4 2-(5-methyl-1H-indol-3-yl)-N,N-dimethylethylamine 
• 128102-50-1 phenyl-(5-phenyl-[1,2,4]oxadiazol-3-yl)-methanone p-tolyl-hydrazone 
• 80815-86-7 N-[1-Phenyl-1-(5-phenyl-[1,2,4]oxadiazol-3-yl)-meth-(Z)-ylidene]-N'-p-tolyl-hydrazine 
• 103409-84-3 ethyl 1-(4-tolyl)-3-methyl-5-(2-nitrobenzyl)pyrazole-4-carboxylate 
• 81016-47-9 5-Methyl-4-nitro-2H-pyrazole-3-carboxylic acid N'-p-tolyl-hydrazide 
• 51626-88-1 6-methyl-2,3-dihydro-1H-carbazol-4(9H)-one 
• 87650-45-1 3,5-Dimethyl-4-(5-oxo-1-p-tolyl-2,5-dihydro-1H-pyrazol-3-yl)-1H-pyrrole-2-carboxylic acid ethyl ester 

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Preparation method of 4-methyl phenylhydrazine hydrochloride

The invention relates to a preparation method of 4-methyl phenylhydrazine hydrochloride. The preparation method comprises the following steps: diazotization, reduction, purification and salt formation. In the diazotization and reduction steps, reaction liquid is kept with high acidity by means of concentrated hydrochloric acid, so that the reaction is smoothly and fully carried out. In the reduction step, zinc powder-concentrated hydrochloric acid is taken as a reducing agent to replace sodium thiosulfate, sodium hydrogen sulfite, stannous chloride-hydrochloric and the like, the reducing property is good, the yield is high, the reaction time is shortened, impurities such as zinc hydroxide generated by the reaction are conveniently removed, and the product is few in impurity and high in purity. In the salt formation step, acetone is used to wash, so that the purity of the product is improved, and the appearance of the product is ensured. According to the preparation method, the processis stable and reliable, the operation is easy, the product purity is high (the content of the product detected by high performance liquid chromatography is greater than or equal to 99%), the yield isgreater than or equal to 39%, and the demand on 4-methyl phenylhydrazine hydrochloride in the market is fully met.