تفاعل #72544
ord-506deeb5f54946d7a3c2fa62f0204408
معادلة التفاعل
الكواشف
المذيبات
ظروف التفاعل
المعالجة
- 1درجة الحرارةmaintaining the temperature between −60° C. and −55° C
- 2أخرىis brought to 0° C.
- 3workup.STIRRINGAfter stirring for 12 hours at ambient temperature
- 4أخرىthe phases are separated
- 5غسيلthe organic phase is washed successively with aq. 2M HCl solution, water
- 6تجفيفThe organic phase is dried over sodium sulphate
- 7ترشيحfiltered
- 8أخرىevaporated to dryness
- 9أخرىThe residue obtained
- 10أخرىThe crystals obtained
- 11ترشيحare filtered off
- 12غسيلwashed with ether
- 13أخرىdried in vacuo
الإجراء التجريبي
To a solution of ethyl 4-amino-benzoate (40.0 g) in DCM (900 ml) at −60° C. there is added, dropwise, ethyl(methylsulphanyl)acetate (34.5 ml) under a nitrogen atmosphere. 29.0 g of tBuOCl are then added, dropwise, to the reaction mixture over 25 minutes, maintaining the temperature between −60° C. and −55° C. After stirring for one hour at −50° C., triethylamine (15.4 ml) is added dropwise. The reaction mixture is brought to 0° C. and then aqueous 3M HCl solution (485 ml) is added dropwise. After stirring for 12 hours at ambient temperature, the phases are separated and the organic phase is washed successively with aq. 2M HCl solution, water and then sat. aqueous NaCl solution. The organic phase is dried over sodium sulphate, filtered and evaporated to dryness. The residue obtained is taken up in ether. The crystals obtained are filtered off, washed with ether and dried in vacuo to yield the title product, which is used directly in the next Step.