تفاعل #2341

معادلة التفاعل

diethyl azodicarboxylate

Methyl-4-hydroxy-3-vinylbutyrate

4-[4-(4-pyridyl)piperazin-1-yl]phenol

triphenylphosphine

→

ammonium hydroxide

methyl 4-[4-[4-(4-pyridyl)piperazin-1-yl]-phenoxy]-3-vinylbutyrate

المردود 19.6%

المذيبات

dichloromethane

ظروف التفاعل

المعالجة

1. 1
   أخرىwas obtained
2. 2
   workup.STIRRINGthe mixture stirred for 4 hours
3. 3
   أخرىThe solid which had precipitated during the reaction
4. 4
   ترشيحwas filtered off
5. 5
   أخرىThe filtrate was evaporated
6. 6
   workup.ADDITIONthe residue treated with ethyl acetate (20 ml)
7. 7
   ترشيحfiltered
8. 8
   استخلاصThe filtrate was extracted with 2N hydrochloric acid (2×10 ml)
9. 9
   أخرىthe aqueous layer separated
10. 10
    استخلاصThe precipitate was extracted twice into ethyl acetate
11. 11
    ترشيحthe combined extracts filtered through phase
12. 12
    أخرىseparating paper
13. 13
    أخرىevaporated
14. 14
    أخرىThe residue was purified by flash chromatography on silica gel
15. 15
    غسيلeluting with methanol/dichloromethane/0.89 S

الإجراء التجريبي

To a stirred suspension of 4-[4-(4-pyridyl)piperazin-1-yl]phenol (1.98 g) in dichloromethane (30 ml) at 15° C. was added triphenylphosphine (2.04 g) followed by dropwise addition of diethyl azodicarboxylate (1.35 g). The mixture was stirred until complete solution was obtained. Methyl-4-hydroxy-3-vinylbutyrate (1.12 g) was added dropwise and the mixture stirred for 4 hours. The solid which had precipitated during the reaction was the starting phenol and was filtered off. The filtrate was evaporated and the residue treated with ethyl acetate (20 ml) and filtered. The filtrate was extracted with 2N hydrochloric acid (2×10 ml) and the aqueous layer separated and basified with 0.89 S.G. ammonium hydroxide. The precipitate was extracted twice into ethyl acetate and the combined extracts filtered through phase separating paper and evaporated. The residue was purified by flash chromatography on silica gel, eluting with methanol/dichloromethane/0.89 S. G. ammonium hydroxide v:v:v 7.5/92.5/0.75 to give RS methyl 4-[4-[4-(4-pyridyl)piperazin-1-yl]-phenoxy]-3-vinylbutyrate (0.29 g); NMR(CDCl3) δ 8.3(2H,d), 6.88(4H,m), 6.70(2H,d), 5.85(1H,m), 5.20(2H,m), 3.90(2H,m), 3.67(3H,s), 3.48(2H,m), 3.18(2H,m), 3.06(1H,m), 2.68(1H,m), 2.47(1H,m), 1.80(1H,br); m/e 382 (M+H)+.

المصدر