Réaction #10021

Équation de réaction

sodium hydrogencarbonate

(S)-2-Boc-aminobutanol

TEMPO

sodium bromide

→

(S)-2-(tert-butoxycarbonyl)-amino-butyraldehyde

Rendement 77.0%

Solvants

dichloromethane

water

Conditions de réaction

Traitement

1. 1
   workup.ADDITIONdiluted bleach (1.3 eq, 450 mL)
2. 2
   workup.ADDITIONwas added over 40 min
3. 3
   workup.STIRRINGThe reaction mixture was stirred for 30 min. at 0° C.
4. 4
   Autrequenched with aq. thiosulfate
5. 5
   ExtractionAfter decantation and extractions (dichloromethane)
6. 6
   Lavagethe organic phase was washed with brine
7. 7
   Autredried
8. 8
   Concentrationconcentrated in vacuo to dryness

Mode opératoire

To a solution of (S)-2-Boc-aminobutanol (50 g; 264 mmol) in dichloromethane (500 mL) and water (350 mL) were added at 20° C. TEMPO (0.01 eq), sodium bromide (1 eq) and sodium hydrogencarbonate (3 eq). The reaction mixture was stirred at 0° C. and diluted bleach (1.3 eq, 450 mL) was added over 40 min. The reaction mixture was stirred for 30 min. at 0° C. and then quenched with aq. thiosulfate. After decantation and extractions (dichloromethane), the organic phase was washed with brine, dried and concentrated in vacuo to dryness, giving (S)-2-(tert-butoxycarbonyl)-amino-butyraldehyde as a low-melting solid (38.1 g; yield: 77%). C9H17NO3; MW=187.2; Tmelt=44° C.; NMR (CDCl3, ppm): 0.97 (t, J=7 Hz, 3H), 1.45 (s, 9H), 1.68 (m, 1H), 1.91 (m, 1H), 4.20 (lq, J=6.5 Hz, 1H), 5.09 (1s, 1H (mobile)) and 9.59 (s, 1H); SM (EI; m/z): 158 (M+—CHO), 102, 57.

Source