تفاعل #440280

معادلة التفاعل

Chlorotrimethylsilane

3,5-heptanedione

dimethylsulphoxide

→

title compound

المردود 43.4%

4-Chloro-3,5-heptanedione

المردود 43.4%

المذيبات

water

acetonitrile

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةThe resulting solution was cooled in ice
2. 2
   أخرىproducing a yellow solution which
3. 3
   workup.STIRRINGstirred for 10 min
4. 4
   استخلاصextracted with ether (1×500 ml, 2×250 ml)
5. 5
   تجفيفThe combined ether layers were dried over magnesium sulphate
6. 6
   ترشيحfiltered
7. 7
   تركيزconcentrated under reduced pressure
8. 8
   أخرىto leave a yellow oil
9. 9
   workup.DISTILLATIONThe crude product was purified by distillation under reduced pressure

الإجراء التجريبي

Chlorotrimethylsilane (29.7 ml, 0.234 mol) was added dropwise to a stirred pale yellow solution of tetrabutylammonium bromide (1.26 g, 3.9 mmol) in dry acetonitrile (116 ml) at room temperature under nitrogen. The resulting solution was cooled in ice and 3,5-heptanedione (10.6 ml, 78.0 mmol) and then dry dimethylsulphoxide (16.6 ml, 0.234 mol) were added dropwise over 5 minutes producing a yellow solution which was allowed to warm slowly to room temperature, with stirring, over 4 hours. The mixture was diluted with water (1 litre), stirred for 10 min and then extracted with ether (1×500 ml, 2×250 ml). The combined ether layers were dried over magnesium sulphate, filtered and concentrated under reduced pressure to leave a yellow oil. The crude product was purified by distillation under reduced pressure to afford the title compound (5.5 g) as a pale yellow oil, b.p. 102-105° C./54 mmHg containing ca. 10% 4,4-dichloro-3,5-heptanedione as estimated by microanalysis.

المصدر