624-67-9

Basic information

• Product Name: PROPYNAL
• Synonyms: PROPYNAL;2-propynal;Propiolaldehyde;PROPIOALDEHYDE;PROPYNAL TECH.;2-Propyn-1-al;2-Propyne-1-one;Propiolic aldehyde
• CAS NO: 624-67-9
• Molecular Formula: C₃H₂O
• Molecular Weight: 54.04738
• EINECS: 210-857-4
• Mol File: 624-67-9.mol
• Article Data: 35

Chemical Properties

• Melting Point: 121-122 °C
• Boiling Point: 58.85°C
• Flash Point: 4.8°C
• Appearance: /
• Density: 0.9152
• Vapor Pressure: 196mmHg at 25°C
• Refractive Index: 1.3963 (estimate)
• CAS DataBase Reference: PROPYNAL(CAS DataBase Reference)
• NIST Chemistry Reference: PROPYNAL(624-67-9)
• EPA Substance Registry System: PROPYNAL(624-67-9)

Safety Data

• Statements: 10
• Safety Statements: 16
• RIDADR: 1989
• Hazardous Substances Data: 624-67-9(Hazardous Substances Data)

Usage

Enzyme inhibitor

This aldehyde (FW = 54.048 g/mol; CAS 624-67-9), also known as propynal, synthesized from propargyl alcohol, is an irreversible inhibitor of aldehyde dehydrogenases.

InChI:InChI=1/C3H2O/c1-2-3-4/h1,3H

Synthetic route

10-(1-methoxy-2-propynyl)phenothiazine → Propargylic aldehyde (624-67-9) + 10H-phenothiazine (92-84-2)

Conditions	Yield
With sulfuric acid In 1,4-dioxane at 18℃;	A n/a B 95%

propargyl alcohol (107-19-7) → Propargylic aldehyde (624-67-9)

Conditions	Yield
With chromium(VI) oxide; sulfuric acid In water; butanone at 20 - 25℃; for 5h;	91%
With chromium(VI) oxide; sulfuric acid In water; butanone at 20 - 25℃; under 760.051 Torr; for 1h;	90%
With C6H12N2*2ClCrO3(1-)*2H(1+) In dichloromethane at 20℃; for 2h;	85%

9-(1-methoxy-2-propynyl)carbazole → Propargylic aldehyde (624-67-9) + 9H-carbazole (86-74-8)

Conditions	Yield
With sulfuric acid In 1,4-dioxane at 18℃;	A n/a B 84%

dipropargyl ether (6921-27-3) → Propargylic aldehyde (624-67-9) + 1,2-propanediene (463-49-0)

Conditions	Yield
at 750℃; under 0.001 - 0.01 Torr;	A 80% B n/a

N-methyl-3-formylindole (19012-03-4) + acetylenemagnesium bromide (4301-14-8) → Propargylic aldehyde (624-67-9) + 3,3'-(prop-2-yne-1,1-diyl)bis(1-methyl-1H-indole)

Conditions	Yield
In tetrahydrofuran at 0℃; for 12h;	A n/a B 68%

DL-erythro-pentyne-(1)-triol-(3.4.5) (62842-54-0) → Propargylic aldehyde (624-67-9)

Conditions	Yield
With sodium periodate; water

phenyl propargyl sulfide (5651-88-7) → Propargylic aldehyde (624-67-9)

Conditions	Yield
With tert-butylhypochlorite In ethanol

N-methylpropargylamine (35161-71-8) → Propargylic aldehyde (624-67-9)

Conditions	Yield
Yield given. Multistep reaction;

N-propargylbenzylamine (1197-51-9) → Propargylic aldehyde (624-67-9) + benzaldehyde (100-52-7)

Conditions	Yield
Yield given. Multistep reaction. Yields of byproduct given;

(Z)-1-methoxybut-1-en-3-yne (2798-73-4, 3685-19-6, 3685-20-9) → Propargylic aldehyde (624-67-9) + Methyl formate (107-31-3)

Conditions	Yield
With air In chloroform-d1 for 1440h; Product distribution; Ambient temperature; daylight;

N-(ethyl)propargylamine (6943-44-8) → Propargylic aldehyde (624-67-9)

Conditions	Yield
Yield given. Multistep reaction;

butyl(prop-2-ynyl)amine (44768-33-4) → Propargylic aldehyde (624-67-9)

Conditions	Yield
Yield given. Multistep reaction;

2-diazo-1-(2-cyclopropen-1-yl)ethanone (94923-08-7) → 3-buten-1-yne (689-97-4) + Propargylic aldehyde (624-67-9) + 1,3-cyclobutadiene (1120-53-2) + acetylene (74-86-2)

Conditions	Yield
at 450℃; bei 1E-6 Torr;
at 450℃; Irradiation; bei 1E-6 Torr;

1,2-dioxacyclohexa-3,4-diene → Propargylic aldehyde (624-67-9) + formaldehyd (50-00-0)

Conditions	Yield
Thermodynamic data;

propargyl alcohol methyl ether (627-41-8) → Propargylic aldehyde (624-67-9)

Conditions	Yield
With glucose-6-phosphate dehydrogenase; (S)-2-[3]pyridyl-pyrrolidine-1-carboxylic acid amide; D-glucose 6-phosphate; sodium phosphate buffer; rat liver microsomes; potassium chloride; semicarbazide hydrochloride; NADP; magnesium chloride other propargyllic comp.;

propargyl alcohol (107-19-7) + diluted Cr2O3-H2SO4 → Propargylic aldehyde (624-67-9)

sulfuric acid (7664-93-9) + propargyl alcohol (107-19-7) → Propargylic aldehyde (624-67-9) + Propiolic acid (471-25-0)

Conditions	Yield
elektrochemische Oxydation an einer Bleidioxid-Anode;

acetylene (74-86-2) + carbon monoxide → Propargylic aldehyde (624-67-9)

Conditions	Yield
With steam; vanadia at 600℃;

diethyl-acetal → Propargylic aldehyde (624-67-9)

Conditions	Yield
With sulfuric acid

dimethyl-acetal → Propargylic aldehyde (624-67-9)

Conditions	Yield
With sulfuric acid

hydrogenchloride (7647-01-0) + N,N'-prop-2-ynylidene-bis-carbamic acid diethyl ester (857829-15-3) → Propargylic aldehyde (624-67-9)

DL-erythro-pentyne-(1)-triol-(3.4.5) (62842-54-0) + water (7732-18-5) + sodium periodate → Propargylic aldehyde (624-67-9) + formaldehyd (50-00-0) + formic acid (64-18-6)

hydrogenchloride (7647-01-0) + 3-ethynyl-2,4-diaza-glutaric acid diamide → Propargylic aldehyde (624-67-9) + urea (57-13-6)

hydrogenchloride (7647-01-0) + N,N'-bis-(1-ureido-prop-2-ynyl)-urea → Propargylic aldehyde (624-67-9) + urea (57-13-6)

formic acid (64-18-6) + Propiolaldehyde diethyl acetal (10160-87-9) → Propargylic aldehyde (624-67-9) + formic acid ethyl ester (109-94-4)

Conditions	Yield
at 20℃; for 3h; Esterification; Formolysis; Title compound not separated from byproducts;

Propiolaldehyde diethyl acetal (10160-87-9) → Propargylic aldehyde (624-67-9)

Conditions	Yield
With sulfuric acid; hydroquinone at 80℃;
With hydrogenchloride at 40℃; for 0.5h;

propargyl alcohol (107-19-7) → Propargylic aldehyde (624-67-9) + Propiolic acid (471-25-0)

Conditions	Yield
With air; RuO2 incorporated in ZSM-5 zeolite In toluene at 80℃; under 630.8 Torr; for 32h;

Propiolaldehyde diethyl acetal (10160-87-9) → Propargylic aldehyde (624-67-9) + propynal hydrate + 1-ethoxy-prop-2-yn-1-ol (73506-25-9)

Conditions	Yield
With amberlyst-15; water In [D3]acetonitrile at 25℃;

dipropargyl ether (6921-27-3) → Propargylic aldehyde (624-67-9)

Conditions	Yield
Flash vacuum pyrolysis;

Propargylic aldehyde (624-67-9) + (9S)-9-Methyl-1-phenylbicyclo<4.3.0>nona-1(2),3(4)-diene (126971-21-9) → (1R,3aS,7aS)-7a-Methyl-1-phenyl-1,4,5,6,7,7a-hexahydro-1,3a-etheno-indene-9-carbaldehyde (126971-22-0)

Conditions	Yield
In benzene under 4875390 Torr; for 12h; Heating;	100%

Propargylic aldehyde (624-67-9) + bis(2-phenylethyl)phosphine oxide (27440-52-4) → 1-(diphenethylphosphoryl)-2-propyn-1-ol

Conditions	Yield
In tetrahydrofuran at -10 - 22℃; for 0.5h;	100%

Propargylic aldehyde (624-67-9) + 2-methyl-5-<(tert-butyldimethylsilyl)oxy>-1,3-pentadiene (179815-45-3) → 1-formyl-6-<((tert-butyldimethylsilyl)oxy)methyl>-4-methyl-1,4-cyclohexadiene (104329-44-4)

Conditions	Yield
In benzene at 120℃;	98%
With hydroquinone In benzene at 110 - 120℃; for 24h;	98%

Propargylic aldehyde (624-67-9) + (E)-methyl 2-(3-(2-(tert-butoxycarbonylamino)ethyl)-5-fluoro-1H-indol-2-yl)-3-methoxyacrylate → (3aR,11a1R)-3-tert-butyl 6-methyl 10-fluoro-4-formyl-3a,7-dihydro-1H-pyrrolo[2,3-d]carbazole-3,6(2H)-dicarboxylate

Conditions	Yield
Stage #1: (E)-methyl 2-(3-(2-(tert-butoxycarbonylamino)ethyl)-5-fluoro-1H-indol-2-yl)-3-methoxyacrylate With C19H24N2O; trichloroacetic acid In dichloromethane at 0℃; for 0.25h; Stage #2: Propargylic aldehyde In dichloromethane at 0℃;	97%

Propargylic aldehyde (624-67-9) + (E)-methyl 2-(3-(2-(benzyloxycarbonylamino)ethyl)-1H-indol-2-yl)-3-methoxyacrylate → (3aR,11a1R)-3-benzyl 6-methyl 4-formyl-3a,7-dihydro-1H-pyrrolo[2,3-d]carbazole-3,6(2H)-dicarboxylate

Conditions	Yield
Stage #1: (E)-methyl 2-(3-(2-(benzyloxycarbonylamino)ethyl)-1H-indol-2-yl)-3-methoxyacrylate With C19H24N2O; trichloroacetic acid In dichloromethane at 0℃; for 0.25h; Stage #2: Propargylic aldehyde In dichloromethane at 0℃;	96%

Propargylic aldehyde (624-67-9) + O,O-dimethyl phosphorodithioic acid (756-80-9) → 3-(dimethoxyphosphinothioylthio)acrolein (95601-21-1)

Conditions	Yield
In tetrachloromethane at 25℃; for 16h;	95%

Propargylic aldehyde (624-67-9) → β-(E)-iodoacrolein (151160-05-3)

Conditions	Yield
With sulfuric acid; sodium iodide In diethyl ether; water at 0℃; for 2h; Inert atmosphere;	95%
With sulfuric acid; sodium iodide In diethyl ether; water at 0℃; for 1h;	83%

Propargylic aldehyde (624-67-9) + C20H19BrN2O4S → C23H21BrN2O5S

Conditions	Yield
With (2S,5S)-5-benzyl-2-(tert-butyl)-3-methylimidazolidin-4-one; trichloroacetic acid In toluene at 10℃; Michael Addition; enantioselective reaction;	95%

Propargylic aldehyde (624-67-9) + 3-Methoxy-17-phenyl-1,3,5(10),14(15),16(17)-estrapentaene (109900-56-3) → C28H28O2 (109900-44-9)

Conditions	Yield
	94%
In dichloromethane under 4875390 Torr; for 24h; Ambient temperature;	93%

Propargylic aldehyde (624-67-9) + (E)-ethyl 2-(3-(2-(tert-butoxycarbonylamino)ethyl)-1H-indol-2-yl)-3-ethoxyacrylate → (3aR,11a1R)-3-tert-butyl 6-ethyl 4-formyl-3a,7-dihydro-1H-pyrrolo[2,3-d]carbazole-3,6(2H)-dicarboxylate

Conditions	Yield
Stage #1: (E)-ethyl 2-(3-(2-(tert-butoxycarbonylamino)ethyl)-1H-indol-2-yl)-3-ethoxyacrylate With C19H24N2O; trichloroacetic acid In dichloromethane at 0℃; for 0.25h; Stage #2: Propargylic aldehyde In dichloromethane at 0℃;	94%

Propargylic aldehyde (624-67-9) + (E)-ethyl 2-(3-(2-(benzyloxycarbonylamino)ethyl)-1H-indol-2-yl)-3-ethoxyacrylate → (3aR,11a1R)-3-benzyl 6-ethyl 4-formyl-3a,7-dihydro-1H-pyrrolo[2,3-d]carbazole-3,6(2H)-dicarboxylate

Conditions	Yield
Stage #1: (E)-ethyl 2-(3-(2-(benzyloxycarbonylamino)ethyl)-1H-indol-2-yl)-3-ethoxyacrylate With C19H24N2O; trichloroacetic acid In dichloromethane at 0℃; for 0.25h; Stage #2: Propargylic aldehyde In dichloromethane at 0℃;	94%

methanol (67-56-1) + Propargylic aldehyde (624-67-9) + (E)-methyl 2-(3-(2-acetoxyethyl)-1H-indol-2-yl)-3-methoxyacrylate → (4S,4aS)-methyl 4a-(2-acetoxyethyl)-3-formyl-4-methoxy-4a,9-dihydro-4H-carbazole-1-carboxylate

Conditions	Yield
Stage #1: methanol; (E)-methyl 2-(3-(2-acetoxyethyl)-1H-indol-2-yl)-3-methoxyacrylate With C19H24N2O; trichloroacetic acid In dichloromethane at 0℃; for 0.25h; Stage #2: Propargylic aldehyde In dichloromethane at 0℃;	94%

Propargylic aldehyde (624-67-9) + 2,2,2-trifluoroethanol (75-89-8) → trifluoroethoxy acrolein

Conditions	Yield
With sodium ethanolate In tetrahydrofuran at 0℃; for 0.5h; Temperature; Reagent/catalyst; Solvent;	93.2%

Propargylic aldehyde (624-67-9) + phosphonic acid diethyl ester (762-04-9) → (1-hydroxy-prop-2-ynyl)-phosphonic acid diethyl ester (13337-18-3)

Conditions	Yield
With triethylamine	93%
With sodium ethanolate

Propargylic aldehyde (624-67-9) + (E)-methyl 2-(5-bromo-3-(2-(tert-butoxycarbonylamino)ethyl)-1H-indol-2-yl)-3-methoxyacrylate → (3aR,11a1R)-3-tert-butyl 6-methyl 10-bromo-4-formyl-3a,7-dihydro-1H-pyrrolo[2,3-d]carbazole-3,6(2H)-dicarboxylate

Conditions	Yield
Stage #1: (E)-methyl 2-(5-bromo-3-(2-(tert-butoxycarbonylamino)ethyl)-1H-indol-2-yl)-3-methoxyacrylate With C19H24N2O; trichloroacetic acid In dichloromethane at 0℃; for 0.25h; Stage #2: Propargylic aldehyde In dichloromethane at 0℃;	93%

Propargylic aldehyde (624-67-9) + (E)-methyl 3-methoxy-2-(3-(2-(methoxycarbonylamino)ethyl)-1H-indol-2-yl)acrylate → (3aR,11a1R)-dimethyl 4-formyl-3a,7-dihydro-1H-pyrrolo[2,3-d]carbazole-3,6(2H)-dicarboxylate

Conditions	Yield
Stage #1: (E)-methyl 3-methoxy-2-(3-(2-(methoxycarbonylamino)ethyl)-1H-indol-2-yl)acrylate With C19H24N2O; trichloroacetic acid In dichloromethane at 0℃; for 0.25h; Stage #2: Propargylic aldehyde In dichloromethane at 0℃;	93%

Propargylic aldehyde (624-67-9) + (E)-methyl 2-{3-[2-(tert-butoxycarbonylamino)ethyl]-1H-indol-2-yl}-3,3-dimethoxypropanoate → (3aR,11a1R)-3-tert-butyl 6-methyl 4-formyl-3a,7-dihydro-1H-pyrrolo[2,3-d]carbazole-3,6(2H)-dicarboxylate

Conditions	Yield
Stage #1: (E)-methyl 2-{3-[2-(tert-butoxycarbonylamino)ethyl]-1H-indol-2-yl}-3,3-dimethoxypropanoate With C19H24N2O; trichloroacetic acid In dichloromethane at 0℃; for 0.25h; Stage #2: Propargylic aldehyde In dichloromethane at 0℃; for 0.5h; Reagent/catalyst; Solvent; Time;	93%

benzoimidazole (51-17-2) + Propargylic aldehyde (624-67-9) → (E)-3-Benzoimidazol-1-yl-propenal (21431-76-5)

Conditions	Yield
	92%

Propargylic aldehyde (624-67-9) → (+/-)-(1-2H)prop-2-yn-1-ol (61208-19-3)

Conditions	Yield
With sodium borodeuteride In water at 5℃; for 0.5h;	92%

Propargylic aldehyde (624-67-9) + 2-Iodophenol (533-58-4) → (E)-3-(2-hydroxyphenyl)propenal (60125-23-7)

Conditions	Yield
Stage #1: Propargylic aldehyde; 2-Iodophenol With diethoxymethylsilane; [RhCl(PPh3)3]/Pd(OAc)2/polyammonium iodide gel In 1,4-dioxane at 60℃; for 2h; Stage #2: With tetrabutyl ammonium fluoride In tetrahydrofuran; 1,4-dioxane at 60℃; for 12h; Hiyama cross-coupling reaction; Further stages.;	92%

Propargylic aldehyde (624-67-9) + C20H20N2O4S → C23H22N2O5S

Conditions	Yield
With (2S,5S)-5-benzyl-2-(tert-butyl)-3-methylimidazolidin-4-one; trichloroacetic acid In toluene at 10℃; Catalytic behavior; Reagent/catalyst; Solvent; Michael Addition; enantioselective reaction;	92%

Propargylic aldehyde (624-67-9) + C17H18N2O3 → C20H20N2O4

Conditions	Yield
With (2S,5S)-5-benzyl-2-(tert-butyl)-3-methylimidazolidin-4-one; trichloroacetic acid In toluene at 10℃; Michael Addition; enantioselective reaction;	92%

methanol (67-56-1) + Propargylic aldehyde (624-67-9) + (E)-methyl 2-(3-(2-azidoethyl)-1H-indol-2-yl)-3-methoxyacrylate → (4S,4aS)-methyl 4a-(2-azidoethyl)-3-formyl-4-methoxy-4a,9-dihydro-4H-carbazole-1-carboxylate

Conditions	Yield
Stage #1: methanol; (E)-methyl 2-(3-(2-azidoethyl)-1H-indol-2-yl)-3-methoxyacrylate With C19H24N2O; trichloroacetic acid In dichloromethane at 0℃; for 0.25h; Stage #2: Propargylic aldehyde In dichloromethane at 0℃;	92%

Propargylic aldehyde (624-67-9) + 5-Hydroxy-3-methyl-5H-furan-2-one (931-23-7) → (E)-3-[(4-methyl-5-oxo-2H-furan-2-yl)oxy]prop-2-enal

Conditions	Yield
With 4-methyl-morpholine In tetrahydrofuran at 0℃; for 0.25h; Michael Addition; diastereoselective reaction;	92%

Propargylic aldehyde (624-67-9) + 1H-benzimidazol-2-amine (934-32-7) → (E)-3-(2-Amino-benzoimidazol-1-yl)-propenal (107113-21-3)

Conditions	Yield
	90%

Propargylic aldehyde (624-67-9) + benzyl bromide (100-39-0) → 1-(phenylmethyl)-1H-1,2,3-triazole-4-carboxaldehyde (124940-34-7)

Conditions	Yield
With sodium azide; copper(II) sulfate; sodium L-ascorbate In water; tert-butyl alcohol at 120℃; for 0.2h; Huisgen cycloaddition; Microwave irradiation; regioselective reaction;	90%

Propargylic aldehyde (624-67-9) + bromobenzene (108-86-1) → 1-Phenyl-2-propyn-1-ol (4187-87-5)

Conditions	Yield
Stage #1: bromobenzene With iodine; magnesium In tetrahydrofuran Inert atmosphere; Stage #2: Propargylic aldehyde In tetrahydrofuran at -78℃; Inert atmosphere;	90%
With magnesium In tetrahydrofuran; diethyl ether	58.1%

Propargylic aldehyde (624-67-9) + (E)-methyl 2-(3-(2-(tert-butoxycarbonylamino)ethyl)-5-methyl-1H-indol-2-yl)-3-methoxyacrylate → (3aR,11a1R)-3-tert-butyl 6-methyl 4-formyl-10-methyl-3a,7-dihydro-1H-pyrrolo[2,3-d]carbazole-3,6(2H)-dicarboxylate

Conditions	Yield
Stage #1: (E)-methyl 2-(3-(2-(tert-butoxycarbonylamino)ethyl)-5-methyl-1H-indol-2-yl)-3-methoxyacrylate With C19H24N2O; trichloroacetic acid In dichloromethane at 0℃; for 0.25h; Stage #2: Propargylic aldehyde In dichloromethane at 0℃;	90%

Upstream product

• 6921-27-3 dipropargyl ether 
• 7664-93-9 sulfuric acid 
• 107-19-7 propargyl alcohol 
• 62842-54-0 DL-erythro-pentyne-⁽¹⁾-triol-(3.4.5) 
• 7732-18-5 water 
• 7647-01-0 hydrogenchloride 
• 19012-03-4 N-methyl-3-formylindole 
• 4301-14-8 acetylenemagnesium bromide 
• 68-12-2 N,N-dimethyl-formamide 
• 74-86-2 acetylene 
• 10160-87-9 Propiolaldehyde diethyl acetal 
• 64-18-6 formic acid 
• 857829-15-3 N,N'-prop-2-ynylidene-bis-carbamic acid diethyl ester 
• 627-41-8 propargyl alcohol methyl ether 

Downstream Products

• 34899-99-5 (E)-3-(piperidin-1-yl)acrylaldehyde 
• 7383-19-9 hept-1-yn-3-ol 
• 82372-60-9 3-diphenylamino-acrylaldehyde 
• 58836-15-0 1,4-cyclohexadiene-1-carboxaldehyde 
• 91-22-5 quinoline 
• 58836-16-1 4-methyl-cyclohexa-1,4-dienecarbaldehyde 
• 59951-57-4 trans,s-trans-3-Cyclohexylamino-2-propen-1-on 
• 39254-62-1 2--1.3.4-triaza-2.4-heptadien-6-in 
• 21431-75-4 (E)-3-(1H-imidazol-1-yl)acrylaldehyde 
• 4652-35-1 3-methoxyacrolein 
• 19060-10-7 3,3-dimethoxypropanal 
• 107113-20-2 (E)-3-(2-Methyl-benzoimidazol-1-yl)-propenal 
• 74824-71-8 (Z)-3-(Phenylseleno)acrylaldehyde 
• 74824-70-7 (E)-3-(Phenylseleno)acrylaldehyde 

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