Reaktion #83734

ord-9f7b13d930d8406cbb70db21fd4dac26

Lösungsmittel

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    FiltrationThe resulting benzylamine-p-nitrobenzenesulphonic acid salt is filtered off
  2. 2
    Einengenthe filtrate is concentrated by evaporation
  3. 3
    Filtrationfiltered over silica gel with toluene
  4. 4
    Sonstigerecrystallised from ether/petroleum ether
  5. 5
    Sonstige[α]D20 =+22° (3% in CHCl3), m.p. 68°-70° C., IR (CH2Cl2) 1752, 1678, 1632 cm-1

Vorschrift

At 0° C., 25.5 g of benzylamine are added dropwise within a period of 1 hour to a solution of 35.7 g of (R)-2-(4-nitrobenzenesulphonyloxy)-3-methoxycarbonyl-2-penten-4-olide in 250 ml of methylene chloride. The resulting benzylamine-p-nitrobenzenesulphonic acid salt is filtered off, and the filtrate is concentrated by evaporation, filtered over silica gel with toluene, and recrystallised from ether/petroleum ether. [α]D20 =+22° (3% in CHCl3), m.p. 68°-70° C., IR (CH2Cl2) 1752, 1678, 1632 cm-1.

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US05625059uspto-grants-1997_04