Related Experiment Video
Updated: May 23, 2025

A Protocol for Safe Lithiation Reactions Using Organolithium Reagents
Published on: November 12, 2016
A Lewis Base-Free Trialumane: Enhanced Electrophilicity Based on Consecutive Vacant Orbitals Over Three Aluminum
Ryotaro Yamanashi1, Chaoqi Chen2, Takumi Moriyama2
1Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Tokai National Higher Education and Research System, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8603, Japan.
Abstract:
A Lewis base-free trialumane having a 2,4,6-triisopropylphenyl (Tip) substituent was synthesized by a reaction of alumanyl anion with TipAlBr2. The structure, bonding, and electronic properties of the Tip-substituted trialumane were estimated by NMR spectra, X-ray crystallographic analysis, DFT calculations, X-ray photoelectron spectra, and electrochemical study to reveal its two consecutive Al─Al covalent bonds and overlapped vacant orbitals of three Al atoms. Chemical reduction of Tip-substituted trialumane gave a series of alumanyl anions via the cleavage of the Al─Al bonds. This study shows the low-lying characteristic LUMO that consists of vacant orbitals of three Al atoms in the base-free trialumane.
Related Concept Videos
π Molecular Orbitals of the Allyl Radical
The allyl systems have identical molecular orbitals but differ in the number of π electrons....
Electrophilic Addition to Alkynes: Halogenation
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
π Molecular Orbitals of the Allyl Cation and Anion
Hydroboration-Oxidation of Alkenes
Aromatic Hydrocarbon Cations: Structural Overview
Removing one hydrogen from the intervening CH2 group...
Radical Reactivity: Nucleophilic Radicals

