تفاعل #1375810

ord-f6d22957050f4aed9bebef8c0aae1fb2

المذيبات

ظروف التفاعل

الظروف التفصيلية
See reaction.notes.procedure_details.

المعالجة

  1. 1
    أخرىafter substantial evaporation of methanol, it
  2. 2
    workup.STIRRINGis shaken out with ethyl acetate
  3. 3
    تجفيفThe organic phase is dried on anhydrous magnesium sulfate
  4. 4
    ترشيحfiltered
  5. 5
    تركيزconcentrated by evaporation
  6. 6
    أخرىThe residue is chromatographed on silica gel with diethyl ether/hexane/triethylamine
  7. 7
    تركيزconcentrated by evaporation

الإجراء التجريبي

16.9 g (71.5 mmol) of tyrosine-tert-butyl ester and 8.33 g (78.6 mmol) of benzaldehyde are stirred in 50 ml of methanol for 3 hours at 24° C. and then mixed with 3.37 g (53.6 mmol) of sodium cyanoborohydride. After 24 hours of stirring at room temperature, the batch is adjusted to pH 2 by careful addition of semiconcentrated hydrochloric acid, then neutralized with concentrated aqueous sodium bicarbonate solution and, after substantial evaporation of methanol, it is shaken out with ethyl acetate. The organic phase is dried on anhydrous magnesium sulfate, filtered and concentrated by evaporation. The residue is chromatographed on silica gel with diethyl ether/hexane/triethylamine; the product-containing fractions are combined and concentrated by evaporation.

المصدر

DOI: 10.6084/m9.figshare.5104873.v1براءة الاختراع: US05746995uspto-grants-1998_05