تفاعل #59249

معادلة التفاعل

MgSO4

NaOAc

3-Methyl-2-oxo-butyric acid ethyl ester

butyl-hydrazine oxalate salt

→

crude product ( 3b )

المردود 85.4%

2-(Butyl-hydrazono)-3-methyl-butyric acid ethyl ester

المردود 85.4%

المذيبات

CHCl3

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةThe mixture was heated
2. 2
   درجة الحرارةto reflux for 3.5 hours under N2 atmosphere
3. 3
   درجة الحرارةAfter cooling
4. 4
   ترشيحthe solid was filtered off
5. 5
   تركيزthe filtrate was concentrated under reduced vacuum
6. 6
   استخلاصThe residue was first cleaned by an extraction between EtOAc (50 mL×3) and H2O (20 mL)
7. 7
   تركيزThe organic layer was concentrated under reduced pressure
8. 8
   أخرىdried under high vacuum overnight

الإجراء التجريبي

To a solution of 3-Methyl-2-oxo-butyric acid ethyl ester (1c) (1.88 g, 13.04 mmol) in 45 mL of CHCl3, butyl-hydrazine oxalate salt (2.11 g, 11.85 mmol) was added followed by NaOAc (1.94 g, 23.4 mmol) and MgSO4 (1.43 g, 11.88 mmol). The mixture was heated to reflux for 3.5 hours under N2 atmosphere with stirring. After cooling, the solid was filtered off and the filtrate was concentrated under reduced vacuum. The residue was first cleaned by an extraction between EtOAc (50 mL×3) and H2O (20 mL). The organic layer was concentrated under reduced pressure and dried under high vacuum overnight to give 2.17 g of the crude product (3b) in 85.4% yield as a mixture of the E- and Z-isomers. This crude product was directly used in the next step without further purification. LC-MS (ESI+): m/e=215.4 [M+1]+, 237.1 [M+Na]+ (exact ms: 214.17).

المصدر