Abstract
This review highlights the advances in the literature up to July
2008 on the intermolecular reactions of acyclic and cyclic N -acyliminium ions. This is an update
of an earlier review in 2000 on this topic and does not include
intramolecular addition reactions to N -acyliminium
ions which was recently reviewed. This review is presented in two
parts, with the first part having dealt with acyclic and pyrrolidinone-based N -acyliminium ions. Part II continues
with other five-membered heterocyclic derivatives and higher systems.
Part I
1 Introduction
2 Acyclic N -Acyliminium Ions
2.1 Synthesis of Acyclic N -Acyliminium
Ion Precursors
2.2 Reactions of Acyclic N -Acyliminium
Ions
2.2.1 Reactions with Nucleophiles
2.2.2 Cycloaddition Reactions
2.2.3 Cationic Carbohydroxylation Reactions
3 Cyclic N -Acyliminium Ions
3.1 Synthesis of Cyclic N -Acyliminium
Ion Precursors
3.1.1 Preparation of Iminium Ions in situ by Anodic Oxidation
3.2 Five-Membered-Ring N -Acyliminium
Ions
3.2.1 Reactions of Pyrrolidinone-Based N -Acyliminium
Ions
Part II
3.2.2 Reactions of N -Acylpyrrolidine-Based N -Acyliminium Ions with Nucleophiles
3.2.2.1 Silicon-Based Nucleophiles
3.2.2.2 Aromatic Nucleophiles
3.2.2.3 Organostannanes
3.2.2.4 Organometallic Reagents
3.2.2.5 Carbonyl Compounds
3.2.2.6 Alkyl Radicals
3.2.2.7 Thiols
3.2.2.8 Active Methylene Compounds
3.2.3 Reactions of Oxazolidinone-Based N -Acyliminium
Ions with Nucleophiles
3.2.3.1 Silicon-Based Nucleophiles
3.2.3.2 Organometallic Reagents
3.2.3.3 Active Methylene Compounds
3.2.4 Cyclocondensation Reaction of N -Aminidinyl
Iminium Ions
3.3 Reactions of Six-Membered-Ring N -Acyliminium
Ions
3.3.1 Reactions of Piperidinone-Based N -Acyliminium
Ions with Nucleophiles
3.3.1.1 Silicon-Based Nucleophiles
3.3.1.2 Organostannanes
3.3.1.3 Organometallic Reagents
3.3.2 Reactions of N -Acylpiperidine-Based N -Acyliminium Ions
3.3.2.1 Reactions with Nucleophiles
3.3.2.2 Cycloaddition Reactions
3.3.3 Reactions of Piperazine-Based N -Acyliminium
Ions with Nucleophiles
3.3.3.1 Silicon-Based Nucleophiles
3.3.3.2 Aromatic Nucleophiles
3.3.4 Reactions of Pyridine-Based N -Acyliminium
Ions with Nucleophiles
3.3.4.1 Organometallic Reagents
3.3.5 Reactions of N ,O -Acetal Oxathiazinane N -Sulfonyliminium
Ions with Nucleophiles
3.3.5.1 Organometallic Reagents
3.4 Reactions of Seven-Membered-Ring N -Acyliminium
Ions
3.4.1 Reactions with Silicon-Based Nucleophiles
3.4.2 Cycloaddition Reactions
3.5 Reactions of Bicyclic N -Acyliminium
Ions
3.5.1 Reactions with Nucleophiles
3.5.1.1 Silicon-Based Nucleophiles
3.5.1.2 Organometallic Reagents
3.5.1.3 Enamines
3.5.2 Cycloaddition Reactions
3.6 Other Systems
3.6.1 Silicon-Based Nucleophiles
4 Stereochemical Outcomes
5 Conclusions
Key words
N -acyliminium ion - nucleophilic
addition - cycloaddition - aromatic electrophilic
substitution - radical addition - peptides - pyrrolidines - piperidines
