Reaktion #303830

Reaktionsgleichung

Methanesulfonic acid

(2R)-2-phenylcarbonyloxypropyl (2S)-2-(tert-butoxycarbonyl)amino-3-(3,4-dihydroxyphenyl)propanoate

(2R)-2-Phenylcarbonyloxypropyl (2S)-2-(tert-Butoxycarbonyl)amino-3-(3,4-dihydroxyphenyl)propanoate

methyl tert-butyl ether

→

mesylate salt

Ausbeute 54.4%

(2R)-2-Phenylcarbonyloxypropyl (2S)-2-Amino-3-(3,4-dihydroxyphenyl)propanoate Mesylate

Ausbeute 54.4%

Lösungsmittel

1,4-dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGThe reaction mixture was stirred for 2 h
2. 2
   FiltrationThe resulting suspension was filtered
3. 3
   WaschenThe filter cake was washed three times with methyl tert-butyl ether and air
4. 4
   Sonstigedried

Vorschrift

Methanesulfonic acid (3.9 mL, 60.1 mmol) was slowly added to a solution of (2R)-2-phenylcarbonyloxypropyl (2S)-2-(tert-butoxycarbonyl)amino-3-(3,4-dihydroxyphenyl)propanoate 2 (11.0 g, 22.1 mmol) in 1,4-dioxane (30 mL) while stirred at room temperature. The reaction mixture was stirred for 2 h. The solution was slowly added to methyl tert-butyl ether (MTBE) (600 mL) with vigorous stirring. The resulting suspension was filtered. The filter cake was washed three times with methyl tert-butyl ether and air dried to afford 5.48 g (54% yield) of the mesylate salt 1 as an off-white solid.

Quelle