Related Experiment Video
Updated: May 21, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Carbon-based leaving group in substitution reactions: functionalization of sp3-hybridized quaternary and tertiary
Stuart J Mahoney1, Tiantong Lou, Ganna Bondarenko
1Department of Chemistry, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada.
Abstract:
Lewis acid promoted substitution reactions employing Meldrum's acid and 5-methyl Meldrum's acid as carbon-based leaving groups are described which transform unstrained quaternary and tertiary benzylic C(sp(3))-C(sp(3)) bonds into C(sp(3))-X bonds (X = C, H, N). Importantly, this reaction has a broad scope in terms of both suitable substrates and nucleophiles with good to excellent yields obtained (typically >90%).
More Related Videos
Related Concept Videos
Nucleophilic Aromatic Substitution: Elimination–Addition
Carbocations
Reactions at the Benzylic Position: Halogenation
Preparation of Alcohols via Substitution Reactions
Alcohols can be synthesized from alkyl halides via nucleophilic substitution reactions. The highly polar carbon-halogen bond in the substrate makes halide a good leaving group. The hydroxide ion or water can act as a nucleophile to take the place of halide and form an alcohol. The substitution reactions occur via two different reaction pathways, SN1 or SN2, depending on the nature of carbon attached to the halide.
Primary alcohols are synthesized from primary alkyl halides, and the...
Leaving Groups
In general, in a nucleophilic substitution reaction, a nucleophile displaces a functional group, called the leaving group, from the substrate to give a substituted product. A leaving group departs the substrate molecule through heterolytic cleavage, taking the pair of electrons with it to become a relatively stable weak base in the form of an anion or a neutral molecule.
In a nucleophilic...
Electrophilic Aromatic Substitution: Sulfonation of Benzene

