ISSN:
1573-9171
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Summary 1. A general method has been developed for the preparation ofa,β-unsaturated cyclic ketones. There are two stages: bromination of a cyclic ketone in presence of calcium or magnesium carbonate; and elimination of hydrogen bromide from the bromo ketone formed, which is effected by heating it in presence of diethylaniline. 2. 2-Methyl-2-cyclohexen-1-one (58% yield), 2-methyl-2-cyclopenten-1-one (50% yield), 2-cyclohexen-1-one (35% yield), and 2-cyclopentea-1-one (25% yield) have been prepared by this method. 3. It has been proved that, in the bromination of 2-methylpyclohexanone and of 2-methylcyclopentanone, bromine attacks the tertiary carbon atom, and not a secondary carbon, as assured previously by some workers. 4. The method of preparing 2,4-dimethyl-2-cyclopenten-1-one has been simplified and improved.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01178858
