17814-72-1

Basic information

• Product Name: 3-Hexynoic acid
• Synonyms: 3-Hexynoic acid
• CAS NO: 17814-72-1
• Molecular Formula: C₆H₈O₂
• Molecular Weight: 112.12652
• Mol File: 17814-72-1.mol
• Article Data: 7

Chemical Properties

• Melting Point: 27°C (estimate)
• Boiling Point: 250.67°C (rough estimate)
• Appearance: /
• Density: 1.0900 (rough estimate)
• Refractive Index: 1.3925 (estimate)
• CAS DataBase Reference: 3-Hexynoic acid(CAS DataBase Reference)
• NIST Chemistry Reference: 3-Hexynoic acid(17814-72-1)
• EPA Substance Registry System: 3-Hexynoic acid(17814-72-1)

Safety Data

• Hazardous Substances Data: 17814-72-1(Hazardous Substances Data)

Upstream product

• 1002-28-4 3-hexyn-1-ol 
• 93604-63-8 hex-3-ynenitrile 
• 81981-05-7 methyl 3,4-hexadienoate 
• 16400-32-1 1-bromo-pent-2-yne 
• 87498-17-7 methyl hex-3-ynoate 

Downstream Products

• 2313-01-1 5-ethyl-2(3H)-furanone 

Relevant articles and documents

Atom-Economical Cross-Coupling of Internal and Terminal Alkynes to Access 1,3-Enynes

Selective carbon-carbon (C-C) bond formation in chemical synthesis generally requires prefunctionalized building blocks. However, the requisite prefunctionalization steps undermine the overall efficiency of synthetic sequences that rely on such reactions, which is particularly problematic in large-scale applications, such as in the commercial production of pharmaceuticals. Herein, we describe a selective and catalytic method for synthesizing 1,3-enynes without prefunctionalized building blocks. In this transformation several classes of unactivated internal acceptor alkynes can be coupled with terminal donor alkynes to deliver 1,3-enynes in a highly regio- and stereoselective manner. The scope of compatible acceptor alkynes includes propargyl alcohols, (homo)propargyl amine derivatives, and (homo)propargyl carboxamides. This method is facilitated by a tailored P,N-ligand that enables regioselective addition and suppresses secondary E/Z-isomerization of the product. The reaction is scalable and can operate effectively with as low as 0.5 mol % catalyst loading. The products are versatile intermediates that can participate in various downstream transformations. We also present preliminary mechanistic experiments that are consistent with a redox-neutral Pd(II) catalytic cycle.

Palladium(II)-Catalyzed Directed anti-Hydrochlorination of Unactivated Alkynes with HCl

A regioselective anti-hydrochlorination of unactivated alkynes is reported. The reaction utilizes in situ generated HCl as the source of both the Cl- and H+ and is catalyzed by palladium(II) acetate, with loadings as low as 25 ppm. Removable picolinamide and 8-aminoquinoline bidentate directing groups are used to control the regioselectivity of the chloropalladation step and stabilize the resulting alkenylpalladium(II) intermediate for subsequent protodepalladation. This method provides access to a broad array of substituted alkenyl chlorides in excellent yields and with high regioselectivity. The products from this transformation were successfully derivatized via Stille coupling to a variety of trisubstituted alkene products. Reaction progress kinetic analysis was performed, shedding light on a possible mechanism for this catalytic process.

Highly enantioselective direct vinylogous Michael addition of γ-butenolide to enals

An unprecedented and simple direct vinylogous addition of deconjugated butenolide to enals has been developed in excellent stereoselectivities (>95% ee), with Aminal-PYrrolidine (APY) catalyst. This methodology allows for the efficient preparation of comp