Selenium Oxide Elimination
The selenium-elimination is one of the reactions to mildesten from alcohols one by cis-elimination alkene to win. The selenium oxides can be obtained from corresponding selenides by oxidation and are often produced in situ by oxidation at low temperatures. The elimination occurs spontaneously during warming to room temperature.
mechanism
The mechanism runs through a five-membered transition state that shifts three electron pairs.
Sulfoxide elimination
Sulfoxide elimination was known even before selenium oxide elimination. Since sulfoxides are more stable than selenium oxides, the final elimination step for sulfoxides only takes place at elevated temperatures. This can be a disadvantage if other groups in the molecule to be synthesized are thermally labile. However, it can also be advantageous because the sulfoxide function can be introduced in an early step, in the meantime serves as a protective group for the double bond to be synthesized and can only be eliminated after several further synthetic steps .
See also
Individual evidence
- ^ Reinhard Brückner : Advanced Organic Chemistry . San Diego, Harcourt, 2002, ISBN 0-12-138110-2 .