Réaction #494368

Équation de réaction

L-Alanine

NAD

pyridoxal-5-phosphate

sodium phosphate dibasic

(3S)-3-(benzyloxy)tetrahydro-4H-pyran-4-one

HCl

sodium formate

potassium carbonate

→

(3R,4S)-3-(benzyloxy)tetrahydro-2H-pyran-4-amine

Solvants

ethyl acetate

water

Conditions de réaction

Traitement

1. 1
   workup.DISSOLUTIONAfter all the components were completely dissolved
2. 2
   Autreaged at 30° C
3. 3
   FiltrationThe mixture was filtered through a bed of Solka Floc
4. 4
   Lavagethe cake was washed with ethyl acetate (250 mL)
5. 5
   AutreThe combined filtrates were separated
6. 6
   Extractionthe aqueous layer was extracted a second time with ethyl acetate (2 L)
7. 7
   ConcentrationThe combined organic extracts were concentrated in vacuo

Mode opératoire

To a solution of L-Alanine (200 g, 2.24 mol), sodium formate (76.0 g, 1.12 mmol), and sodium phosphate dibasic (28.7 g, 202 mmol) in 2.25 L of water adjusted to pH 7.5 was added NAD (2.2 g, 3.21 mmol), pyridoxal-5-phosphate (2.2 g, 8.90 mmol), LDH (0.45 g, 0.22 mol), FDH (4.5 g, 0.20 mol), and TA P1G5 (4.5 g, 0.22 mol) [CDX TA P1G5=Codex Transaminase panel enzyme P1G5, which is commercially available from Codexis (Redwood City, Calif., USA)]. After all the components were completely dissolved, (3S)-3-(benzyloxy)tetrahydro-4H-pyran-4-one (45 g, 0.22 mol) was added and the pH was adjusted to pH 7.25 with 6 N HCl and aged at 30° C. After 15 h, potassium carbonate (700 g, 5.06 mol) was added slowly, followed by ethyl acetate (2.2 L). The mixture was filtered through a bed of Solka Floc and the cake was washed with ethyl acetate (250 mL). The combined filtrates were separated and the aqueous layer was extracted a second time with ethyl acetate (2 L). The combined organic extracts were concentrated in vacuo to provide crude (3R,4S)-3-(benzyloxy)tetrahydro-2H-pyran-4-amine.

Source