反応 #2286309

反応方程式

cyano-(2,6-dichloro-4-nitro-phenyl)-acetic acid tert-butyl ester

Cyano-(2,6-dichloro-4-nitrophenyl)-acetic acid tert-butyl ester

hydrochloric acid

sodium carbonate

tin(II) chloride dihydrate

tin(II) chloride dihydrate

→

(4-amino-2,6-dichloro-phenyl)-acetonitrile

収率 58.0%

溶媒

ethanol

ethyl acetate

反応条件

後処理

1. 1
   その他The reaction was fitted with a reflux condenser
2. 2
   温度the reaction was warmed to 110-115° C. where it
3. 3
   温度At this time, the reaction was cooled to 25° C.
4. 4
   ろ過The resulting thick mixture was filtered
5. 5
   ろ過through filter paper
6. 6
   ろ過via vacuum filtration
7. 7
   洗浄was washed with ethyl acetate until no material
8. 8
   その他The filtrate was then transferred to a separatory funnel
9. 9
   その他where the resulting layers were separated
10. 10
    洗浄The organics were washed consecutively with a 1N aqueous hydrochloric acid solution (1×250 mL)
11. 11
    乾燥The organics were then dried with magnesium sulfate
12. 12
    ろ過filtered
13. 13
    濃縮concentrated under vacuum

実験手順

A solution of cyano-(2,6-dichloro-4-nitro-phenyl)-acetic acid tert-butyl ester (43) (78.69 g, crude) in ethanol (320 mL) at 25° C. was treated with concentrated hydrochloric acid (160 mL). The reaction was fitted with a reflux condenser and then was heated to 75° C. At this time, the resulting homogeneous solution was treated portion wise with tin(II) chloride dihydrate (225.64 g, 1.0 mol). Upon complete addition of the tin(II) chloride dihydrate, the reaction was warmed to 110-115° C. where it was stirred for 3 h. At this time, the reaction was cooled to 25° C. and then was diluted with ethyl acetate (1.5 L). The resulting solution was carefully neutralized with a saturated aqueous sodium carbonate solution (1.0 L). The resulting thick mixture was filtered through filter paper via vacuum filtration and was washed with ethyl acetate until no material was detected in the filtrate. The filtrate was then transferred to a separatory funnel where the resulting layers were separated. The organics were washed consecutively with a 1N aqueous hydrochloric acid solution (1×250 mL), a saturated aqueous sodium carbonate solution (1×250 mL), a 1N aqueous hydrochloric acid solution (1×250 mL), and a saturated aqueous sodium chloride solution (1×250 mL). The organics were then dried with magnesium sulfate, filtered, and concentrated under vacuum. Flash chromatography (Merck Silica gel 60, 230-400 mesh, 80/20 hexanes/ethyl acetate) afforded (4-amino-2,6-dichloro-phenyl)-acetonitrile (44) (25.95 g, 58%) as a yellow solid; EL-HRMS m/e calcd for C8H6Cl2N2 (M+) 199.9908, found 199.9906. Exact Mass=199.9908; Molecular Weight=201.06.

出典