反応 #87140

反応方程式

Iodine

(R)-methyl 2-(tert-butoxycarbonylamino)-3-iodopropanoate

6-Bromo-2-(2,4-dimethoxybenzyl)-3,4-dihydro-2H-benzo[e][1,2]thiazine 1,1-dioxide

S—Phos

iodine

→

(R)-methyl 2-((tert-butoxycarbonyl)amino)-3-(2-(2,4-dimethoxybenzyl)-1,1-dioxido-3,4-dihydro-2H-benzo[e][1,2]thiazin-6-yl)propanoate

収率 46.0%

溶媒

DMF

反応条件

後処理

1. 1
   workup.STIRRINGThe mixture was stirred for another 1 h
2. 2
   workup.STIRRINGThe reaction mixture was stirred at 50° C. for 4 h
3. 3
   ろ過The mixture was filtered
4. 4
   workup.ADDITIONthe filtrate was poured into water (50 mL)
5. 5
   抽出The resulting mixture was extracted with EtOAc (100 mL×3)
6. 6
   乾燥dried over anhydrous sodium sulfate
7. 7
   濃縮concentrated
8. 8
   その他The residue was purified by flash column chromatography on silica gel (petroleum ether/EtOAc=15:1 to 3:1)

実験手順

Iodine (0.11 g, 0.43 mmol) was added to a mixture of (R)-methyl 2-(tert-butoxycarbonylamino)-3-iodopropanoate (1.30 g, 3.58 mmol) and zinc (0.620 g, 9.75 mmol) in DMF (30 mL). The mixture was stirred for 10 min and another portion of iodine (0.11 g, 0.43 mmol) was added. The mixture was stirred for another 1 h. 6-Bromo-2-(2,4-dimethoxybenzyl)-3,4-dihydro-2H-benzo[e][1,2]thiazine 1,1-dioxide (1.34 g, 3.25 mmol), Pd2(dba)3 (0.08 g, 0.09 mmol) and S—Phos (0.070 g, 0.17 mmol) were added. The reaction mixture was stirred at 50° C. for 4 h and then cooled to ambient temperature. The mixture was filtered and the filtrate was poured into water (50 mL). The resulting mixture was extracted with EtOAc (100 mL×3). The organic extracts were combined, dried over anhydrous sodium sulfate, and concentrated. The residue was purified by flash column chromatography on silica gel (petroleum ether/EtOAc=15:1 to 3:1) to afford (R)-methyl 2-((tert-butoxycarbonyl)amino)-3-(2-(2,4-dimethoxybenzyl)-1,1-dioxido-3,4-dihydro-2H-benzo[e][1,2]thiazin-6-yl)propanoate (0.8 g, 46% yield) as a yellow oil.

出典