تفاعل #169649

معادلة التفاعل

NAD

Potassium carbonate

4,4-dimethoxydihydro-2H-pyran-3(4H)-one

NaOH

potassium dihydrogenphosphate

sodium formate

L-Alanine

→

(3S)-4,4-dimethoxytetrahydro-2H-pyran-3-amine

المذيبات

toluene

toluene

acetonitrile

ظروف التفاعل

المعالجة

1. 1
   استخلاصextracted 3× with water (270 mL)
2. 2
   workup.ADDITIONwere added
3. 3
   درجة الحرارةcooled to rt
4. 4
   workup.WAITAfter 30 min
5. 5
   ترشيحthe reaction was filtered through a pad of solka-floc
6. 6
   أخرىThe filtrate was partitioned
7. 7
   استخلاصthe aqueous layer was extracted with additional acetonitrile (810 mL)
8. 8
   تركيزThe combined organic fractions were concentrated in vacuo

الإجراء التجريبي

A solution of 4,4-dimethoxydihydro-2H-pyran-3(4H)-one (172 g, 1.07 mol, see Example 1) in 310 mL of toluene was stirred in toluene for 30 min, then extracted 3× with water (270 mL). To the aqueous solution was added potassium dihydrogenphosphate (14.1 g, 0.104 mol), sodium formate (55.1 g, 0.810 mol), and L-Alanine (72.2 g, 0.810 mol). The pH was adjusted to 7.8 with 5N NaOH, and NAD (0.810 g), PLP (0.810 g), LDH (0.162 g), FDH (1.62 g), and Codexis TA P1 G5 (4.05 g) were added. The mixture was heated to 45° C. for 12 h, then cooled to rt. Potassium carbonate (324 g, 2.34 mol) was added, and after 30 min, the mixture was diluted with acetonitrile (810 mL). After 30 min, the reaction was filtered through a pad of solka-floc. The filtrate was partitioned and the aqueous layer was extracted with additional acetonitrile (810 mL). The combined organic fractions were concentrated in vacuo to provide crude (3S)-4,4-dimethoxytetrahydro-2H-pyran-3-amine.

المصدر