Реакция #64528

Уравнение реакции

THF

2-chloro-5-nitrophenylhydrazine

hydrochloride

2-chloro-5-nitroaniline

→

title compound

Выход 19.0%

5-n-Butyl-2-(2-chloro-5-nitrophenyl)-2,4-dihydro-3H-1,2,4-triazol-3-one

Выход 19.0%

Условия реакции

Обработка

1. 1
   Другое96, 184 (1963), by partitioning between ether and 1N sodium carbonate]
2. 2
   Другоеwas reacted with ethyl N-carbethoxyvalerimidate (from Example 4, Step B)
3. 3
   workup.DISSOLUTIONdissolution of all starting material
4. 4
   ДругоеAfter work-up, the residue was purified by flash chromatography on silica gel (gradient elution with 0.5-5.0% methanol in CH2Cl2)

Методика

By the procedure of Example 4, Step C, 2-chloro-5-nitrophenylhydrazine [generated from the hydrochloride, which was prepared from 2-chloro-5-nitroaniline according to H. Stroh and G. Westphal, Chem. Ber. 96, 184 (1963), by partitioning between ether and 1N sodium carbonate] was reacted with ethyl N-carbethoxyvalerimidate (from Example 4, Step B). Enough THF was added to the reaction mixture to ensure dissolution of all starting material. After work-up, the residue was purified by flash chromatography on silica gel (gradient elution with 0.5-5.0% methanol in CH2Cl2) to give a 19% yield of the title compound as an orange solid, mp 145°-147° C., homogeneous by TLC (19:1 CH2Cl2 --MeOH), mass spectrum (FAB) m/e 297 (M+1)+.

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