Related Experiment Video
Updated: Jul 10, 2025

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Reductive Metallation of Dendralenes and Myrcene Using Dimagnesium(I) Compounds: A Facile Route to Unsaturated
Jeremy C Mullins1, K Yuvaraj1, Madison J Sowden2
1School of Chemistry, Monash University, PO Box 23, Melbourne, VIC, 3800, Australia.
Abstract:
The two-electron reduction of 2,3-dimethylbuta-1,3-diene (DMB) with β-diketiminate and guanidinate substituted dimagnesium(I) compounds has given complexes in which two bidentate amido-magnesium fragments are bridged through the π-system of the DMB dianion, viz. [(LMg)2 (μ-DMB)] (L=Xyl Nacnac, [HC(MeCNXyl)2 ]- , Xyl=2,6-xylyl; or Priso=[(DipN)2 CNPri 2 ]- , Dip=2,6-diisopropylphenyl). Similar double reductions of [4]dendralene (4dend) have afforded the complexes, [(LMg)2 (μ-4dend)] (L=Ar Nacnac, Ar=Xyl or mesityl (Mes); or Priso) in which the 4dend dianion is π-coordinated to the bidentate amido-magnesium fragments. Treatment of several such complexes with THF leads to Z- to E-isomerization of the dendralene fragment, and formation of purely σ-bonded Mg-C interactions in the THF coordinated products [{(Ar Nacnac)(THF)Mg}2 (μ-4dend)] (Ar=Xyl, Mes or Dip). Reaction of myrcene (Myr) with [{(Xyl Nacnac)Mg}2 ] proceeds via reductive coupling of Myr to give a previously unknown acyclic, branched C20 tetra-olefin dianion complex [{(Xyl Nacnac)(THF)Mg}2 (μ-Myr)2 ]. Preliminary reactions of [(LMg)2 (μ-DMB)] with H2 and/or CO yielded a series of products, including novel magnesium hydride compounds, products derived from couplings of CO with the reduced DMB fragment (viz. magnesium dimethylcyclohexadienediolates), and one magnesium cyclopropanetriolate complex from the magnesium(I) induced coupling of DMB with H2 and CO.
More Related Videos
Related Concept Videos
Acid Halides to Alcohols: Grignard Reaction
Grignard reagents are a source of carbanions and function as nucleophiles. The mechanism begins with the nucleophilic attack by the carbanion at the carbonyl carbon of the acid halide to form a tetrahedral intermediate. Next, the carbonyl group is re-formed, and the halide ion departs,...
Acid Halides to Ketones: Gilman Reagent
As shown below, the mechanism proceeds in two steps. First, one of the alkyl groups of the reagent acts as a nucleophile and attacks the acyl carbon of the acid chloride to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen...
Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
Nitriles to Ketones: Grignard Reaction
The mechanism begins with a nucleophilic attack by the Grignard...
Oxymercuration-Reduction of Alkenes
![The Synthesis of [Sn10SiSiMe334]2- Using a Metastable SnI Halide Solution Synthesized via a Co-condensation Technique](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F54498.jpg&w=3840&q=50)
