Kostanecki acylation
From Infogalactic: the planetary knowledge core
The Kostanecki acylation is a method used in organic synthesis to form chromones[1] or coumarins[2] by acylation of O-hydroxyaryl ketones with aliphatic acid anhydrides, followed by cyclization.[3] If benzoic anhydride (or benzoyl chloride) is used, a particular type of chromone called a flavone is obtained.
Contents
Mechanism
The mechanism consists of three well-differentiated reactions:[4][5]
- Phenol O-acylation with formation of a tetrahedral intermediate
- Intramolecular aldol condensation to cyclize and to form a hydroxydihydrochromone
- Elimination of the hydroxyl group to form the chromone (or coumarin)
Examples
See also
References
<templatestyles src="Reflist/styles.css" />
Cite error: Invalid <references> tag; parameter "group" is allowed only.
<references />, or <references group="..." />- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Ellis, G. P. (1977) Chromenes, Chromanones, and Chromones from The Chemistry of Heterocyclic Compounds, Weissberger, A. and Taylor, E. C., eds.; Wiley & Sons: New York, vol. 31, p. 495.
