Tiffeneau-Demjanov Ring Expansion
Published Online: 15 SEP 2010
Copyright © 2010 John Wiley & Sons, Inc. All rights reserved.
Comprehensive Organic Name Reactions and Reagents
How to Cite
2010. Tiffeneau-Demjanov Ring Expansion. Comprehensive Organic Name Reactions and Reagents. 623:2777–2781.
- Published Online: 15 SEP 2010
It is a multistep extension of the Demjanov rearrangement to elongate the carbonyl compounds by one more carbon atom, by means of conversion of the carbonyl compound into a β-amino alcohol followed by diazotization with nitrous acid. Therefore, this reaction is generally known as the Tieffeneau–Demjanov ring enlargement. The study finds that in most cases, the Tiffeneau–Demjanov reaction is used to expand the ring of cyclic ketones. It has been reported that the stereochemistry of migrating carbon is generally retained after the rearrangement. For cyclic ketones, the yield of rearrangement decreases along with increasing ring size. This rearrangement has also some limitations and is considered very useful for the preparation of cyclic ketones.
- steric strain;
- β-amino alcohols