Categories: Organic Chemistry >> Organometallics >> Main Group Metals

Organolithiums: Selectivity for Synthesis

Description

This book, Volume 23 in the Tetrahedron Organic Chemistry series, presents organolithium chemistry from the perspective of a synthetic organic chemist, drawing from the synthetic literature to present a unified overview of how organolithiums can be used to make molecules. The development of methods for the regioselective synthesis of organolithiums has replaced their image of indiscriminate high reactivity with one of controllable and subtle selectivity. Organolithium chemistry has a central role in the selective construction of C-C bonds in both simple and complex molecules, and for example has arguably overtaken aromatic electrophilic substitution as the most powerful method for regioselective functionalisation of aromatic rings. The twin themes of reactivity and selectivity run through the book, which reviews the ways by which organolithiums may be formed and the ways in which they react. Topics include recent advances in directed metallation, reductive lithiation and organolithium cyclisation reactions, along with a discussion of organolithium stereochemistry and the role played by ligands such as (-)-sparteine.

Editorial Review

A great many reactions are possible with organolithium compounds, and an understanding of their reactivity and selectivity is the key to the utility of these reactions.

Jonathan Clayden’s book begins with a general introduction to the properties of lithium organyls in various solvents. Keywords such as “aggregation” are briefly defined, and data on the stability of various organyl groups is collected in tables. The most important additives, which lead to deaggregation and exert a direct influence on the reactivity of the organyl, are mentioned in this introductory chapter. These explanations are easily understood by and are oriented toward the practicing chemist, but students with an interest in organometallics will also find "Organolithiums: Selectivity for Synthesis" quite enjoyable.

The subsequent chapters on specific reactions are quite substantial and hold some surprises. By providing an abundance of quite different reaction examples that demonstrate how selectivity plays a role, which factors it depends upon, and how it can be influenced, this monograph truly lives up to its title. The literature citations are further supplemented with mechanistic commentaries. The present volume provides the reader with significant value, in that the cogent explanations and interesting examples can readily benefit one’s practical work. The comprehensive scope of the literature citations also justifies the use of this book as a reference work.

"Organolithiums: Selectivity for Synthesis" is recommended for every chemist who wishes to become thoroughly acquainted with the potential of organolithium chemistry. Jonathan Clayden has succeeded in conveying this knowledge with succinct commentaries supported by appropriate examples.

Contents

Introduction.
Scope and overview. Organolithiums in solution.

Regioselective Synthesis of Organolithiums by Deprotonation.
General points. Lithiation α to heteroatoms. Ortholithiation. Lateral lithiation. Remote lithiation, andΒ-lithiation of non-aromatic compounds. Superbases. Cooperation, competition and regioselectivity.

Regioselective Synthesis of Organolithiums by X-Li Exchange.
Halogen-lithium exchange. Tin-lithium exchange. Chalcogen-lithium exchange. Phosphorus-lithium exchange.

Regioselective Synthesis of Organolithiums by C-X Reduction.
Reductive lithiation of alkyl and aryl halides. Reductive lithiation of C-O bonds. Reductive lithiation of C-N bonds. Reductive lithiation of C-S bonds. Reductive lithiation of C-C bonds and π-bonds.

Stereoselective and Stereospecific Synthesis of Organolithiums.
Configurational stability of organolithiums. Stereospecific synthesis of organolithiums by X-Li exchange. Diastereoselective deprotonation. Enantioselective deprotonation.


Stereospecific and Stereoselective Substitution Reactions of Organolithiums.
Stereospecific reactions of organolithium compounds. Stereoselective substitution in the presence of chiral ligands.

Regio- and Stereoselective Addition Reactions of Organolithiums.
Intermolecular addition to π bonds: Carbolithiation. Intramolecular addition and substitution reactions: anionic cyclisation.

Organolithium Rearrangements.
Shapiro reaction. Brook rearrangements. [1,2]-Wittig Rearrangements. [2,3]-Wittig Rearrangements.

Organolithiums in Synthesis.
Ochratoxin: ortholithiation and anionic Fries rearrangement. Corydalic acid methyl ester: lateral lithiation. Fredericamycin A: ortho, lateral and α-lithiation. (?)-Atpenin B: metallation of an aromatic heterocycle. Flurbiprofen: metallation with LiCKOR superbases. California Red Scale Pheromone: α- and reductive lithiation C1-C9 of the Bryostatins: diastereoselective bromine-lithium exchange. (S)-1-Methyldodecyl acetate, a Drosophila pheromone: (-)-sparteine assisted enantioselective lithiation. (-)-Paroxetine: (-)-sparteine-promoted asymmetric lithiation and substitution.