Related Experiment Video
Updated: Oct 7, 2026

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Byproduct identification: crystal structure of potassium 2-eth-oxy-2-oxo-acetate
Shannon E Creegan1, James A Ridenour2, Robert J Donnelly3
1US Naval Research Laboratory, Center for Biomolecular Science and Engineering, 4555 Overlook Ave., SW Washington, DC 20375, USA.
Abstract:
Potassium 2-eth-oxy-2-oxo-acetate, K+·C4H5O4 -, was identified as a byproduct in the first step of synthesizing the shelf-stable salt potassium nitro-aceto-nitrile (KNAN). A single crystal of the title salt was obtained by recrystallization of the ethanol filtrate resulting from the purification of the intended product salt, potassium ethyl nitro-cyano-acetate. The asymmetric unit of K+·C4H5O4 -, contains a single potassium cation and a 2-eth-oxy-2-oxo-acetate anion, the ethyl group of which is disordered over two sets of sites in a 0.792 (13):0.208 (13) ratio. The packing is dictated primarily by K-O electrostatic inter-actions and comprises eight bonded oxygen atoms per cation, with distances ranging from 2.706 (2) to 3.053 (4) Å.
Related Concept Videos
Structures of Aldehydes and Ketones
In aldehydes (Figures 1a and 1b), the carbonyl...
IUPAC Nomenclature of Ketones
Nomenclature of Carboxylic Acid Derivatives: Acid Halides, Esters, and Acid Anhydrides
The IUPAC and common names of acid halides are derived from the corresponding carboxylic acids, by changing “ic acid” to “yl halide.” For example, as shown below, the IUPAC name ethanoyl chloride is derived from ethanoic acid, and the common name, acetyl chloride, is obtained from acetic acid.
Alkylation of β-Ketoester Enolates: Acetoacetic Ester Synthesis
Structures of Carboxylic Acid Derivatives
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
Oxidation of Alkenes: Syn Dihydroxylation with Potassium Permanganate

