53293-00-8

Basic information

• Product Name: 5-HEXYNOIC ACID
• Synonyms: 5-HEXYNOIC ACID 98%;4-Ethynylbutyric acid;HEX-5-YNOIC ACID;5-HEXYNOIC ACID;TIMTEC-BB SBB009090;RARECHEM AL BO 1092;5-Hexynoicacid,97%
• CAS NO: 53293-00-8
• Molecular Formula: C₆H₈O₂
• Molecular Weight: 112.13
• EINECS: -0
• Product Categories: Acetylenes;Acetylenic Carboxylic Acids & Their Derivatives;C6;Carbonyl Compounds;Carboxylic Acids
• Mol File: 53293-00-8.mol
• Article Data: 27

Chemical Properties

• Melting Point: 27°C (estimate)
• Boiling Point: 224-225 °C(lit.)
• Flash Point: 230 °F
• Appearance: yellow/Liquid
• Density: 1.016 g/mL at 25 °C(lit.)
• Vapor Pressure: 0.042mmHg at 25°C
• Refractive Index: n20/D 1.449(lit.)
• Storage Temp.: Keep in dark place,Sealed in dry,Room Temperature
• PKA: 4?+-.0.10(Predicted)
• Water Solubility: Miscible with water.
• BRN: 1743192
• CAS DataBase Reference: 5-HEXYNOIC ACID(CAS DataBase Reference)
• NIST Chemistry Reference: 5-HEXYNOIC ACID(53293-00-8)
• EPA Substance Registry System: 5-HEXYNOIC ACID(53293-00-8)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 26-36
• RIDADR: 3265
• WGK Germany: 3
• F: 10-23
• HazardClass: 8
• PackingGroup: III
• Hazardous Substances Data: 53293-00-8(Hazardous Substances Data)

Usage

Chemical Properties

clear yellow liquid

Uses

5-Hexynoic acid is used in the preparation of hex-5-ynoic acid methyl ester by using p-toluenesulfonic acid as a reagent. It is also involved in chemical synthesis.

Definition

ChEBI: A hexynoic acid in which the triple bond is between the carbons at positions 5 and 6.

General Description

5-Hexynoic acid is an alkynoic acid. It undergoes gold-catalyzed cyclization to form the corresponding methylene lactones.

InChI:InChI=1/C6H8O2/c1-2-3-4-5-6(7)8/h1H,3-5H2,(H,7,8)/p-1

Synthetic route

5-hexyl-1-ol (928-90-5) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
With jones' reagent In acetone for 1h; Ambient temperature;	82%
With chromium(VI) oxide; hydrogen cation In acetone	80%
With jones reagent at 0℃;	76%

5-hexyl-1-ol (928-90-5) + water (7732-18-5) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
In hexane; sulfuric acid; acetone	72%

5-hexynonitrile (14918-21-9) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
With sodium hydroxide In water for 10h; Heating;	70%
With potassium hydroxide
With potassium hydroxide In methanol; water Heating;
With potassium hydroxide In ethanol; water for 4h; Heating; Yield given;

5,6-dibromohexanoic acid (279214-91-4) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
With sodium amide In diethyl ether at -33 - 25℃; Dehydrobromination;	70%
With sodium amide In diethyl ether; ammonia at -33℃; for 1.5h;	65%

hex-5-ynoic acid tert-butyl ester (73448-14-3) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
With sodium hydride In N,N-dimethyl-formamide at 70℃; for 20h;	65%

5,6-dibromohexanoic acid (279214-91-4) → hex-5-ynoic acid (53293-00-8) + 6-bromohex-5(E)-enoic acid

Conditions	Yield
With sodium hydroxide; PEG-2000 at 80℃; for 8h; Dehydrobromination;	A 49% B 19.6%

5-hexyl-1-ol (928-90-5) → hex-5-ynoic acid (53293-00-8) + hex-5-ynoic acid hex-5-ynyl ester

Conditions	Yield
With chromium(VI) oxide; sulfuric acid; acetone

5-hexynoic acid ethyl ester (108545-38-6) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
With potassium hydroxide

methanol (67-56-1) + 2-carbonyl-3-butenenitrile (60556-87-8) + allenyltrimethylsilane (14657-22-8) → hex-5-ynoic acid (53293-00-8) + 6-(trimethylsilyl)hex-5-ynoic acid: (101224-43-5)

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

methyl hex-5-ynoate (77758-51-1) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
With potassium hydroxide for 0.5h; Heating;
With water; potassium hydroxide In methanol at 20℃; for 0.5h; Inert atmosphere;

bromobutyric acid (2623-87-2) + lithium acetylide (70277-75-7) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
With ammonia

5,6-dibromohexanoic acid (279214-91-4) → hex-5-ynoic acid (53293-00-8) + 6ξ-bromo-hex-5-enoic acid

Conditions	Yield
With potassium hydroxide

5,6-dibromohexanoic acid (279214-91-4) + ethanolic KOH-solution → hex-5-ynoic acid (53293-00-8) + 6ξ-bromo-hex-5-enoic acid

5,6-dibromohexanoic acid (279214-91-4) → hex-5-ynoic acid (53293-00-8) + hex-4-ynoic acid (41143-12-8) + 6-bromohex-5(E)-enoic acid

Conditions	Yield
With sodium hydroxide; PEG-2000 In water at 82℃; for 8h;

bromobutyric acid (2623-87-2) + lithium acetylide-ethylenediamine complex (1216963-74-4) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
In dimethyl sulfoxide

5-hexenoic acid (1577-22-6) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: Br2 / CH2Cl2 / 1.5 h / -40 °C 2: 65 percent / NaNH2 / diethyl ether; liquid ammonia / 1.5 h / -33 °C View Scheme
Multi-step reaction with 2 steps 1: Br2 / CH2Cl2 / 1.5 h / -40 °C 2: NaOH; PEG-2000 / H2O / 8 h / 82 °C View Scheme
Multi-step reaction with 2 steps 1: petroleum ether; bromine 2: ethanolic KOH-solution View Scheme

5-hexenoic acid (1577-22-6) + Merrifield resin → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: 93.5 percent / Br2 / CH2Cl2 / 1.5 h / -40 °C 2: 70 percent / NaNH2 / diethyl ether / -33 - 25 °C View Scheme
Multi-step reaction with 2 steps 1: 93.5 percent / Br2 / CH2Cl2 / 1.5 h / -40 °C 2: 49 percent / 40 percent aq. NaOH; PEG-2000 / 8 h / 80 °C View Scheme

hex-2-yn-1-ol (764-60-3) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: NaNH2 / various solvent(s) 2: Jones reagent View Scheme

methyl 5-hexenoate (2396-80-7) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
Multi-step reaction with 2 steps 2: aq. KOH / 0.5 h / Heating View Scheme

6-(2-Nitro-phenylselanyl)-hexanoic acid methyl ester (108545-33-1) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
Multi-step reaction with 3 steps 1: 68 percent / aq. H2O2 / tetrahydrofuran / 24 h 3: aq. KOH / 0.5 h / Heating View Scheme

2-(chloromethyl)tetrahydropyran (18420-41-2, 130233-13-5, 130233-14-6) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: NaNH2, liq. NH3 / tetrahydrofuran / -78 °C 2: Jones' reagent / acetone / 0 °C View Scheme

Tetrahydropyran-2-methanol (100-72-1) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
Multi-step reaction with 3 steps 1: SOCl2, pyridine / 10 h / Ambient temperature 2: NaNH2, liq. NH3 / tetrahydrofuran / -78 °C 3: Jones' reagent / acetone / 0 °C View Scheme

pent-1-yn-5-ol (5390-04-5) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
Multi-step reaction with 3 steps 1: pyridine / 0.17 h / -10 °C 2: NaCN / dimethylsulfoxide / 0.5 h / 70 °C 3: KOH / ethanol; H2O / 4 h / Heating View Scheme

4-pentynyl-1-tosylate (77758-50-0) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: NaCN / dimethylsulfoxide / 0.5 h / 70 °C 2: KOH / ethanol; H2O / 4 h / Heating View Scheme

1-chloro-4-pentyne (14267-92-6) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: 53 percent 2: 70 percent / NaOH / H2O / 10 h / Heating View Scheme
Multi-step reaction with 3 steps 1: acetone; sodium iodide 2: aqueous acetone 3: aqueous KOH-solution View Scheme
With hydrogenchloride; potassium hydroxide In water; dimethyl sulfoxide

5-iodopent-1-yne (2468-55-5) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: aqueous acetone 2: aqueous KOH-solution View Scheme

2,2'-ethane-1,2-diylbissulfanyl-bis-ethanol (5244-34-8) → hex-5-ynoic acid (53293-00-8)

Conditions	Yield
With n-butyllithium In hexane

aqueous potassium hydroxide + 5-hexynonitrile (14918-21-9) → hex-5-ynoic acid (53293-00-8)

methanol (67-56-1) + hex-5-ynoic acid (53293-00-8) → methyl hex-5-ynoate (77758-51-1)

Conditions	Yield
With toluene-4-sulfonic acid In dichloromethane for 36h; Reflux;	100%
With toluene-4-sulfonic acid In dichloromethane for 24h; Esterification; Heating;	97%
With toluene-4-sulfonic acid In dichloromethane for 24h; Heating;	96%

hex-5-ynoic acid (53293-00-8) → hex-5-in-carboxyl chloride (55183-45-4)

Conditions	Yield
With oxalyl dichloride Inert atmosphere;	100%
With oxalyl dichloride; N,N-dimethyl-formamide In tetrahydrofuran at 20℃; for 2h; Inert atmosphere;	83%
With oxalyl dichloride; N,N-dimethyl-formamide In benzene at 25 - 35℃; for 2h;	82%

hex-5-ynoic acid (53293-00-8) + methyl iodide (74-88-4) → methyl hex-5-ynoate (77758-51-1)

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide	100%
With potassium carbonate In N,N-dimethyl-formamide at 5℃; for 5h; Cooling with ice;	70%
With potassium carbonate In N,N-dimethyl-formamide

chloro-trimethyl-silane (75-77-4) + hex-5-ynoic acid (53293-00-8) → 6-(trimethylsilyl)hex-5-ynoic acid: (101224-43-5)

Conditions	Yield
Stage #1: hex-5-ynoic acid With n-butyllithium In tetrahydrofuran at -78℃; Inert atmosphere; Stage #2: chloro-trimethyl-silane In tetrahydrofuran at -78 - 0℃; Inert atmosphere; Stage #3: With hydrogenchloride In tetrahydrofuran; water at 0 - 20℃; Inert atmosphere;	100%
Stage #1: hex-5-ynoic acid With n-butyllithium In tetrahydrofuran; hexane at -78℃; for 0.75h; Inert atmosphere; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; hexane at -78 - 20℃; Inert atmosphere; Stage #3: With water; acetic acid In tetrahydrofuran; hexane for 0.333333h;	76%
Stage #1: hex-5-ynoic acid With n-butyllithium In tetrahydrofuran at -78℃; for 0.25h; Inert atmosphere; Stage #2: chloro-trimethyl-silane In tetrahydrofuran at -78 - 20℃; for 4h; Inert atmosphere;	65%
Stage #1: hex-5-ynoic acid With n-butyllithium In tetrahydrofuran at -78℃; for 0.0833333h; Inert atmosphere; Stage #2: chloro-trimethyl-silane In tetrahydrofuran at -78 - 20℃; for 1h; Inert atmosphere; Stage #3: With hydrogenchloride In tetrahydrofuran; water	63%
Stage #1: hex-5-ynoic acid With n-butyllithium In tetrahydrofuran; Petroleum ether at -78℃; Stage #2: chloro-trimethyl-silane In tetrahydrofuran; Petroleum ether at -78 - 0℃;

hex-5-ynoic acid (53293-00-8) → sodium 5-hexynoate (1219440-76-2)

Conditions	Yield
With sodium hydrogencarbonate In water at 20℃; for 0.166667h;	100%
With sodium hydroxide In water

morpholine (110-91-8) + hex-5-ynoic acid (53293-00-8) → 1-morpholinohex-5-yn-1-one (1293915-62-4)

Conditions	Yield
With dmap; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride In dichloromethane at 20℃;	100%
With 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; dmap In dichloromethane at 20℃;	100%
With N-(3-dimethylaminopropyl)-N-ethylcarbodiimide In dichloromethane at 23℃; Inert atmosphere;	62%

hex-5-ynoic acid (53293-00-8) + N,O-dimethylhydroxylamine*hydrochloride (6638-79-5) → N-methoxy-N-methylhex-5-ynamide (217087-88-2)

Conditions	Yield
With dmap; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride In dichloromethane at 25℃; Inert atmosphere;	100%
With dmap; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine In dichloromethane at 0 - 25℃; for 6h;	98%
With dmap; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride In N,N-dimethyl-formamide at 20℃; for 43h;	94%
With 4-methyl-morpholine; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride In dichloromethane at 0 - 20℃; for 16h;

p-nitrobenzene iodide (636-98-6) + hex-5-ynoic acid (53293-00-8) → 6-(4-nitrophenyl)hex-5-ynoic acid (1084898-19-0)

Conditions	Yield
With bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide; triethylamine In tetrahydrofuran at 50℃; for 2h; Inert atmosphere;	100%
With bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide; triethylamine In tetrahydrofuran at 50℃; for 2h; Inert atmosphere;	100%
With dichloro bis(acetonitrile) palladium(II); copper(l) iodide; diisopropylamine; triphenylphosphine at 50℃; for 14h; Inert atmosphere; Schlenk technique;	74%
With bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide; N-ethyl-N,N-diisopropylamine In acetonitrile at 50℃; for 2h; Sonogashira Cross-Coupling; Inert atmosphere;	22%

hex-5-ynoic acid (53293-00-8) + 2,3,5,6-tetraflourophenol (769-39-1) → 2,3,5,6-tetrafluorophenyl hex-5-ynoate (1462237-48-4)

Conditions	Yield
With dmap; dicyclohexyl-carbodiimide In dichloromethane at 20℃; for 24h; Inert atmosphere; Schlenk technique;	100%
With pyridinium p-toluenesulfonate; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride In dichloromethane at 20℃; for 16h; Inert atmosphere;

1,3-dihydroxyacetone dimer (62147-49-3) + hex-5-ynoic acid (53293-00-8) → 2-oxopropane-1,3-diyl bis(hex-5-ynoate)

Conditions	Yield
With dmap; dicyclohexyl-carbodiimide In dichloromethane at 0 - 20℃;	100%

hex-5-ynoic acid (53293-00-8) + 4-Iodophenol (540-38-5) → 6-(4-hydroxyphenyl)hex-5-ynoic acid

Conditions	Yield
With bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide; triethylamine In tetrahydrofuran at 20℃; for 4.5h; Temperature; Inert atmosphere;	100%

1-Boc-2-benzylpiperazine + hex-5-ynoic acid (53293-00-8) → C22H30N2O3

Conditions	Yield
With benzotriazol-1-yloxyl-tris-(pyrrolidino)-phosphonium hexafluorophosphate; triethylamine In N,N-dimethyl-formamide at 20℃; for 3h;	100%

hex-5-ynoic acid (53293-00-8) → 6-methylidenetetrahydro-2-pyrone (5636-66-8)

Conditions	Yield
With [(1,1′-biphenyl-2-yl)di-tert-butylphosphine]gold(I) trifluoromethanesulfonate; silver trifluoromethanesulfonate In chloroform-d1 at 20℃; for 0.0833333h; Reagent/catalyst;	99%
With C42H64P4Pd2S4 at 90℃; for 10h; Inert atmosphere;	98%
With potassium carbonate; gold(I) chloride In acetonitrile at 20℃; for 2h;	97%

N-(2-hydroxy-1-methylethyl)-3-iodobenzamide (863713-59-1) + hex-5-ynoic acid (53293-00-8) → 6-[3-(2-hydroxy-1-methylethylcarbamoyl)phenyl]hex-5-ynoic acid (863713-63-7)

Conditions	Yield
With pyrrolidine; copper(l) iodide; tetrakis(triphenylphosphine) palladium(0) at 20 - 60℃; for 3.3h; Sonogashira Coupling;	99%
Stage #1: N-(2-hydroxy-1-methylethyl)-3-iodobenzamide; hex-5-ynoic acid With copper(l) iodide; tetrakis(triphenylphosphine) palladium(0) at 60℃; for 3h; Sonogashira coupling; Stage #2: N-(2-hydroxy-1-methylethyl)-3-iodobenzamide; hex-5-ynoic acid In water; acetonitrile for 0.333333h; Further stages.;	97%

hex-5-ynoic acid (53293-00-8) + (-)-englerin B → C30H38O5

Conditions	Yield
With dmap; 2,4,6-trichlorobenzoyl chloride; triethylamine In toluene at 20℃; Yamaguchi esterification; Inert atmosphere;	99%

hex-5-ynoic acid (53293-00-8) + cholesterol (57-88-5) → (3β)-cholest-4-en-3yl hex-5-ynoate (949584-04-7)

Conditions	Yield
With dmap; dicyclohexyl-carbodiimide In dichloromethane at 0 - 23℃; for 20h;	99%
With dmap; dicyclohexyl-carbodiimide	59%

2-(2'-hydroxyethylamino)-4,6-di(4'-methoxybenzylamino)-1,3,5-triazine + hex-5-ynoic acid (53293-00-8) → 2-[2'-(5-hexynoyloxy)ethylamino]-4,6-di(4'-methoxybenzylamino)-1,3,5-triazine (1391054-29-7)

Conditions	Yield
With dmap; dicyclohexyl-carbodiimide In tetrahydrofuran at 20℃; for 24h; Inert atmosphere;	99%

hex-5-ynoic acid (53293-00-8) + 2,2-dimethoxy-propane (77-76-9) → methyl hex-5-ynoate (77758-51-1)

Conditions	Yield
With chloro-trimethyl-silane In methanol at 20℃; for 16h;	99%

hex-5-ynoic acid (53293-00-8) → dodeca-5,7-diynedioic acid (28393-04-6)

Conditions	Yield
With oxygen; ammonium chloride; copper(l) chloride In water at 20℃;	98%
Stage #1: hex-5-ynoic acid With acetyl chloride In methanol at 20 - 80℃; for 12h; Inert atmosphere; Schlenk technique; Stage #2: With copper(II) acetate monohydrate In acetonitrile at 80℃; for 4h; Reflux; Further stages;	69%
With ammonium chloride; water; copper(l) chloride Reagens 4: Luft;

hex-5-ynoic acid (53293-00-8) → 3,4-dihydro-6-methyl-2H-pyran-2-one (3740-59-8)

Conditions	Yield
With triphenylphosphine gold (I) chloride; silver trifluoromethanesulfonate In dichloromethane at 20℃; for 16h; Inert atmosphere;	98%
With zinc(II) carbonate

hex-5-ynoic acid (53293-00-8) → 6-bromo-5-hexynoic acid (910028-80-7)

Conditions	Yield
With N-Bromosuccinimide; silver nitrate In acetone for 2h;	98%
With N-Bromosuccinimide; silver nitrate In acetone at 20℃; for 2h;	96%
With N-Bromosuccinimide; silver nitrate In acetone at 20℃; for 2h;	72%

hex-5-ynoic acid (53293-00-8) + 2,3,4,5,6-pentafluorophenol (771-61-9) → pentafluorophenyl 5-hexynoate (1219141-93-1)

Conditions	Yield
With dicyclohexyl-carbodiimide In dichloromethane at 0℃;	98%
With dmap; dicyclohexyl-carbodiimide In dichloromethane at 0 - 20℃; for 1h;	95%
With dicyclohexyl-carbodiimide In tetrahydrofuran at 20℃;

hex-5-ynoic acid (53293-00-8) + C31H35NO7 → C37H41NO8

Conditions	Yield
With dmap; 1,2-dichloro-ethane; N-ethyl-N,N-diisopropylamine In dichloromethane Inert atmosphere;	98%

hex-5-ynoic acid (53293-00-8) → 5-ketohexanoic acid (3128-06-1)

Conditions	Yield
In water at 90℃; for 45h;	98%
With [RhCl2(p-cymene)]2; water at 20℃; for 12h;	86%
With platinum catalyst In water at 37℃; for 30h;	64%

hex-5-ynoic acid (53293-00-8) + methanandamide (157182-49-5) → (+)-{(2R)-2-[(5Z,8Z,11Z,14Z)-icosa-5,8,11,14-tetraenoylamino]propyl} 5-hexynoate (1313514-82-7)

Conditions	Yield
Stage #1: hex-5-ynoic acid With dmap; dicyclohexyl-carbodiimide In dichloromethane at 0℃; for 0.5h; Inert atmosphere; Stage #2: methanandamide In dichloromethane at 20℃; for 10h; Inert atmosphere;	98%

hex-5-ynoic acid (53293-00-8) + (S)-(+)-(2,2-dimethyl-[1,3]dioxolan-4-yl)methanol (22323-82-6) → (2'R)-2,3-O-isopropylidene-2,3-dihydroxy-1-prop-1-yl pent-4-ynoate (1341126-40-6)

Conditions	Yield
With dmap; dicyclohexyl-carbodiimide In dichloromethane at 25℃; for 12h; Inert atmosphere;	98%

hex-5-ynoic acid (53293-00-8) + (2-(4-(tert-butyl)-2-ethoxyphenyl)-4,5-bis(4-chlorophenyl)-4,5-dihydro-1H-imidazol-1-yl)(piperazin-1-yl)methanone → 1-(4-(2-(4-(tert-butyl)-2-ethoxyphenyl)-4,5-bis(4-chlorophenyl)-4,5-dihydro-1H-imidazole-1-carbonyl)piperazin-1-yl)hex-5-yn-1-one

Conditions	Yield
Stage #1: hex-5-ynoic acid With N-ethyl-N,N-diisopropylamine; HATU In N,N-dimethyl-formamide at 0 - 20℃; for 0.5h; Stage #2: (2-(4-(tert-butyl)-2-ethoxyphenyl)-4,5-bis(4-chlorophenyl)-4,5-dihydro-1H-imidazol-1-yl)(piperazin-1-yl)methanone In N,N-dimethyl-formamide at 20℃; for 3h;	98%

formaldehyd (50-00-0) + hex-5-ynoic acid (53293-00-8) + 1-((S)-3-azido-2-isocyanopropyl)benzene (1223635-87-7) → (S)-2-[(1-azido-3-phenylpropan-2-yl)amino]-2-oxoethyl hex-5-ynoate

Conditions	Yield
In methanol at 20℃; Passerini Condensation;	98%

hex-5-ynoic acid (53293-00-8) → (E)-5,6-dibromopent-5-enoic acid

Conditions	Yield
With bromine; magnesium bromide ethyl etherate; sodium bromide In dichloromethane at 20℃;	98%

hex-5-ynoic acid (53293-00-8) + (7S)‐2‐(4‐phenoxyphenyl)‐7‐(piperidin‐4‐yl)‐4H,5H,6H,7H‐pyrazolo[1,5‐a]pyrimidine‐3‐carboxamide → (S)-7-(1-(hex-5-ynoyl)piperidin-4-yl)-2-(4-phenoxyphenyl)-4,5,6,7-tetrahydro-pyrazolo[1,5-a]pyrimidine-3-carboxamide

Conditions	Yield
With dmap; benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride In dichloromethane at 20℃;	98%

Upstream product

• 77758-51-1 methyl hex-5-ynoate 
• 279214-91-4 5,6-dibromohexanoic acid 
• 73448-14-3 hex-5-ynoic acid tert-butyl ester 
• 2623-87-2 bromobutyric acid 
• 1216963-74-4 lithium acetylide-ethylenediamine complex 
• 1577-22-6 5-hexenoic acid 
• 14918-21-9 5-hexynonitrile 
• 5244-34-8 2,2'-ethane-1,2-diylbissulfanyl-bis-ethanol 
• 928-90-5 5-hexyl-1-ol 
• 7732-18-5 water 
• 2468-55-5 5-iodopent-1-yne 
• 14267-92-6 1-chloro-4-pentyne 
• 5390-04-5 pent-1-yn-5-ol 
• 100-72-1 Tetrahydropyran-2-methanol 

Downstream Products

• 108545-38-6 5-hexynoic acid ethyl ester 
• 41143-12-8 hex-4-ynoic acid 
• 28393-04-6 dodeca-5,7-diynedioic acid 
• 1191-85-1 eicosa-5,8,11,14-tetraynoic acid 
• 504-02-9 1,3-cylohexanedione 
• 80810-20-4 13-(2,5-Dimethoxy-3,4,6-trimethyl-phenyl)-trideca-5,8-diynoic acid 
• 55183-45-4 hex-5-in-carboxyl chloride 
• 618863-44-8 4-(5-carboxy-1-pentynyl)-2,6-bis[(R)-4-phenyloxazolin-2-yl]pyridine 
• 906564-59-8 hex-5-ynoic acid 2,5-dioxo-pyrrolidin-1-yl ester 
• 898827-92-4 hex-5-ynoic acid 3-benzyloxycarbonylamino-propyl ester 
• 898827-97-9 hex-5-ynoic acid 5-(toluene-4-sulfonylamino)-pentyl ester 
• 898827-87-7 hex-5-ynoic acid 5-benzyloxycarbonylamino-pentyl ester 
• 73448-14-3 hex-5-ynoic acid tert-butyl ester 
• 928-90-5 5-hexyl-1-ol 

Relevant articles and documents

A concise synthesis of xestospongic acid methyl ester with pancreatic lipase inhibitory activity

Xestospongic acid methyl ester, a naturally brominated fatty acid with potent pancreatic lipase inhibitory activity in vitro, was synthesized from 5-hexynol in 30% total yield.

Palladium-catalysed direct synthesis of optically active dienols

A direct and highly chemo, regio and stereocontrolled method for constructing optically active conjugated dienols is described and illustrated by a short, convenient and efficient synthesis of methyl (9R)-9-hydroxytetradeca-5Z,7E-dienoate(-)-1.

Luminescence modulations of rhenium tricarbonyl complexes induced by structural variations

Octahedral d6 low-spin Re(I) tricarbonyl complexes are of considerable interest as noninvasive imaging probes and have been deeply studied owing to their biological stability, low toxicity, large Stokes shifts, and long luminescence lifetimes. We reported recently the bimodal IR and luminescence imaging of a Re(I) tricarbonyl complex with a Pyta ligand (4-(2-pyridyl)-1,2,3-triazole) in cells and labeled such metal-carbonyl complexes SCoMPIs for single-core multimodal probes for imaging. Re(I) tricarbonyl complexes have unique photophysical properties allowing for their unequivocal detection in cells but also present some weaknesses such as a very low luminescence quantum yield in aqueous medium. Further optimizations would thus be desirable. We therefore developed new Re(I) tricarbonyl complexes prepared from different ancillary ligands. Complexes with benzothiadiazole- triazole ligands show interesting luminescent quantum yields in acetonitrile and may constitute valuable luminescent metal complexes in organic media. A series of complexes with bidentate 1-(2-quinolinyl)-1,2,3-triazole (Taquin) and 1-(2-pyridyl)-1,2,3-triazole (Tapy) ligands bearing various 4-substituted alkyl side chains has been designed and synthesized with efficient procedures. Their photophysical properties have been characterized in acetonitrile and in a H 2O/DMSO (98/2) mixture and compared with those of the parent Quinta- and Pyta-based complexes. Tapy complexes bearing long alkyl chains show impressive enhancement of their luminescent properties relative to the parent Pyta complex. Theoretical calculations have been performed to further characterize this new class of rhenium tricarbonyl complexes. Preliminary cellular imaging studies in MDA-MB231 breast cancer cells reveal a strong increase in the luminescence signal in cells incubated with the Tapy complex substituted with a C12 alkyl chain. This study points out the interesting potential of the Tapy ligand in coordination chemistry, which has been so far underexploited.