Reaktion #314743

Reaktionsgleichung

3

2-tert-Butoxycarbonylamino-3-hydroxy-2-methyl-propionic acid methyl ester

2,2-dimethoxypropane

BF3.OEt2

→

4

Ausbeute 85.0%

2,2,4-Trimethyl-oxazolidine-3,4-dicarboxylic acid 3-tert-butyl ester 4-methyl ester

Ausbeute 85.0%

Lösungsmittel

acetone

Reaktionsbedingungen

Aufarbeitung

1. 1
   EinengenThe reaction mixture was then concentrated in vacuo to an orange oil which
2. 2
   Sonstigewas purified by flash chromatography

Vorschrift

To a stirring solution of 3 (9.342 g, 40 mmol) in acetone (115 mL) in a flame dried round bottom flask under an inert atmosphere was added 2,2-dimethoxypropane (66 mL). To this solution was added BF3.OEt2 (0.30 mL, cat.) and stirring was continued at rt for 2 h. The reaction mixture was then concentrated in vacuo to an orange oil which was purified by flash chromatography to provide 4 (9.392 g, 85%) as a white solid. Rf=0.55 (1:3 EtOAc/hexanes). Compound was observed as an uneven mixture of rotomers.

Quelle