반응 #1869345

반응 방정식

5-amino-3-methylisothiazole-4-carbonitrile

isovaleryl chloride

→

N-(4-cyano-3-methyl-isothiazol-5-yl)-3-methyl-butyramide

수율 88.2%

용매

pyridine

chloroform

CHCl3

반응 조건

후처리

1. 1
   workup.ADDITIONAfter the completion of the addition the reaction mixture
2. 2
   세척washed with water (200 ml), 2N HCl (600 ml)
3. 3
   건조NaHCO3 (200 ml), brine (200 ml) and dried over Na2SO4Concentration of the CHCl3 layer
4. 4
   기타provided the crude product which
5. 5
   기타was triturated from DCM/hexanes ( 1/10)
6. 6
   여과filtered off

실험 절차

To a solution of 5-amino-3-methylisothiazole-4-carbonitrile (method 4) (105.6 g, 0.76 mol) in pyridine (250 ml) at 0° C., isovaleryl chloride (100 g, 0.83 mol) in chloroform (300 ml) was added dropwise. After the completion of the addition the reaction mixture was allowed to warm to r.t. and stirred overnight. The TLC and the MS showed the complete disappearance of the starting material and the reaction mixture was diluted with CHCl3 (600 ml), washed with water (200 ml), 2N HCl (600 ml), satd. NaHCO3 (200 ml), brine (200 ml) and dried over Na2SO4Concentration of the CHCl3 layer provided the crude product which was triturated from DCM/hexanes ( 1/10) and filtered off to isolate N-(4-cyano-3-methyl-isothiazol-5-yl)-3-methyl-butyramide (149.7 g, 88%) as an off-white crystalline solid. 1H NMR (300 MHz) δ 1.04 (d, 6H), 2.18-2.32 (m, 1H), 2.46 (d, 2H), 2.53 (s, 3H), 9.87 (bs, 1H).

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