反応 #5927

反応方程式

potassium carbonate

hydrochloric acid

hydrochloric acid

3-(4-chlorophenyl)-1H-naphtho[2,1-b][1,4]thiazin-2(3H)-one

sodium borohydride

→

3-(4-chlorophenyl)-2,3-dihydro-1H-naphtho[2,1-b][1,4]thiazine

収率 88.0%

溶媒

methanol

tetrahydrofuran

反応条件

後処理

1. 1
   温度the mixture is refluxed for 2 hours
2. 2
   温度After cooling, to the mixture
3. 3
   温度the mixture is further refluxed for 4 hours
4. 4
   抽出extracted with ethyl acetate
5. 5
   洗浄The ethyl acetate layer is washed
6. 6
   その他dried
7. 7
   workup.DISTILLATIONdistilled
8. 8
   その他to remove the solvent
9. 9
   その他The residue is recrystallized from tetrahydrofuran-n-hexane

実験手順

To a solution of 3-(4-chlorophenyl)-1H-naphtho[2,1-b][1,4]thiazin-2(3H)-one (38.45 g) and sodium borohydride (22.32 g) in tetrahydrofuran (1.0 liter) is added dropwise with stirring boron trifluoride etherate complex (100 ml) at room temperature, and the mixture is refluxed for 2 hours. After cooling, to the mixture are added methanol (200 ml), 10% hydrochloric acid (300 ml) and conc. hydrochloric acid (150 ml) in this order and the mixture is further refluxed for 4 hours. To the reaction mixture is added ice water and the mixture is made alkaline with potassium carbonate and extracted with ethyl acetate. The ethyl acetate layer is washed, dried and distilled to remove the solvent. The residue is recrystallized from tetrahydrofuran-n-hexane to give 3-(4-chlorophenyl)-2,3-dihydro-1H-naphtho[2,1-b][1,4]thiazine (32.3 g, yield 88%) as crystals.

出典