反応 #91028

反応方程式

tert-butyl nitrite

methyl 4-amino-3,5-diisopropoxybenzoate

Methyl 4-amino-3,5-diisopropoxybenzoate

HCl

→

methyl 4-chloro-3,5-diisopropoxybenzoate

収率 36.0%

溶媒

MeCN

MeCN

反応条件

後処理

1. 1
   workup.ADDITIONOnce the addition
2. 2
   温度to cool to RT
3. 3
   その他The mixture was partitioned between DCM (10 mL) and aq. ammonia (35%, 5 mL)
4. 4
   その他the phases were separated
5. 5
   洗浄the organic solution was further washed with ammonia solution (17.5%, 10 mL), and brine (2×20 mL)
6. 6
   その他The solvent was removed in vacuo
7. 7
   その他the residue was purified by silica gel chromatography (40 g, 0-100% EtOAc in isohexane)

実験手順

A suspension of copper (I) chloride (129 mg, 1.31 mmol) and tert-butyl nitrite (155 μL, 1.31 mmol) in anhydrous MeCN (2 mL) was stirred at 65° C. A solution of methyl 4-amino-3,5-diisopropoxybenzoate (4) (233 mg, 0.872 mmol) in anhydrous MeCN (1 mL) was added dropwise. Once the addition was complete the mixture was allowed to cool to RT and poured on to 20% HCl (5 mL). The mixture was partitioned between DCM (10 mL) and aq. ammonia (35%, 5 mL), the phases were separated and the organic solution was further washed with ammonia solution (17.5%, 10 mL), and brine (2×20 mL). The solvent was removed in vacuo and the residue was purified by silica gel chromatography (40 g, 0-100% EtOAc in isohexane) to afford methyl 4-chloro-3,5-diisopropoxybenzoate (93 mg, 36% yield) as a colourless oil: m/z 287 [M+H]+ (ES+).

出典