Related Experiment Video
Updated: Jul 18, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Electron-induced reactions in condensed films of acetonitrile and ethane
Imre Ipolyi1, Wilfried Michaelis, Petra Swiderek
1Universität Bremen, Institute of Applied and Physical Chemistry, Fachbereich 2 (Chemie/Biologie), Bremen, Germany.
Abstract:
Reactions in pure and mixed films of C(2)H(6) and CD(3)CN deposited on a Au surface at 35 K have been induced by low-energy electrons and investigated by Thermal Desorption Spectrometry (TDS). The incident electron energy (E(0)) was varied between 5 and 16 eV and a number of different products were identified. Beside the main products, CD(4), CD(3)H, and C(2)D(6), molecules resulting from atom scrambling during radical chain reactions (C(2)H(5)D) and recombination products (CD(3)CD(2)CN and C(2)H(5)CD(3)) were identified while others were characteristically absent. The quantity of the different products varied with E(0). The observed electron-driven processes are in accord with previous findings from gas phase experiments on dissociative electron attachment and electron impact ionization. On this basis, reaction mechanisms leading to the formation of the observed products are suggested for different ranges of E(0).
Related Concept Videos
Preparation of Alkynes: Alkylation Reaction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
Acidity of 1-Alkynes
The acidic strength of hydrocarbons follows the order: Alkynes > Alkenes > Alkanes. The strength of an acid is commonly expressed in units of pKa — the lower the pKa, the stronger the acid. Among the hydrocarbons, terminal alkynes have lower pKa values and are, therefore, more acidic. For example, the pKa values for ethane, ethene, and acetylene are 51, 44, and 25, respectively, as shown here.
Structure and Physical Properties of Alkynes
In nature, compounds containing both carbon and hydrogen are known as "hydrocarbons". Aliphatic hydrocarbons are compounds whose molecules contain saturated single bonds (i.e., alkanes) or unsaturated double or triple bonds. Alkenes contain carbon–carbon double bonds and have a structural formula CnH2n. Unsaturated hydrocarbons containing carbon–carbon triple bonds are called "alkynes" and are structurally represented by the formula CnH2n-2.
The simplest alkyne is ethyne, or...
Carboxylic Acids to Methylesters: Alkylation using Diazomethane
Electrophilic Aromatic Substitution: Friedel–Crafts Acylation of Benzene
Thermal and Photochemical Electrocyclic Reactions: Overview

