反应详情

34.0 g (0.5 mol) of isoprene and then, at 0°-10° C., 75.0 g (0.55 mol) of zinc chloride were added to 350 ml of the solution, prepared according to Example 1, of the amide chloride is isobutyric acid dimethylamide in methylene chloride, while cooling and stirring. Thereafter, 50.0 g (0.5 mol) of triethylamine were added dropwise at the same temperature and, after warming to 20°-25° C., the mixture was heated to reflux and worked up according to Example 2. This gave 40.4 g (58%, relative to isobutyric acid dimethylamide employed) of the ketone of boiling point 109°-110° C./100 mm Hg and nD20 of 1.4518 (contaminated to the extent of about 10% by 2,2,3-trimethyl-3-vinyl-cyclobutanone).

1. customprepared
2. temperaturewhile cooling
3. temperatureafter warming to 20°-25° C.
4. temperaturethe mixture was heated
5. temperatureto reflux