Реакция #1121762

Уравнение реакции

NaH

6

4-Bromopyrrole-2-carboxaldehyde

p-toluenesulfonyl chloride

→

crystals

Выход 68.6%

4-Bromo-2-formyl-N-p-tosylpyrrole

Выход 68.6%

Растворители

THF

Условия реакции

Обработка

1. 1
   workup.WAITAfter 16 h
2. 2
   ДругоеThe reaction mixture was quenched
3. 3
   workup.ADDITIONby adding aqueous NH4Cl
4. 4
   workup.ADDITIONEthyl acetate was added
5. 5
   Другоеthe organic layer was separated
6. 6
   ПромывкаThe organic layer was washed with water, brine
7. 7
   Сушкаdried (Na2SO4)
8. 8
   КонцентрированиеConcentration
9. 9
   Другоеfollowed by crystallization (ethyl acetate/hexanes)

Методика

Following a reported procedure,18 a stirred suspension of NaH (865 mg, 36.0 mmol) in THF (200 mL) was treated with 6 (5.22 g, 30.0 mmol) at room temperature. When the evolution of gas had ceased, the mixture was stirred for 1 h before treating with p-toluenesulfonyl chloride (6.30 g, 33.0 mmol). After 16 h, the conversion was complete as monitored by TLC. The reaction mixture was quenched by adding aqueous NH4Cl. Ethyl acetate was added and the organic layer was separated. The organic layer was washed with water, brine and dried (Na2SO4). Concentration followed by crystallization (ethyl acetate/hexanes) afforded pale yellow crystals (6.75 g, 68%): mp 83-85° C.; 1H NMR δ 2.43 (s, 3H), 7.09 (d, J=2.0 Hz, 1H), 7.35 (d, J=8.3 Hz, 2H), 7.57 (d, J=2.0 Hz, 1H), 7.81 (d, J=8.3 Hz, 2H), 9.94 (s, 1H); 13C NMR δ 22.0, 101.8, 125.4, 127.8, 127.9, 130.6, 133.5, 134.7, 146.7, 178.5. Anal. Calcd or C12H10BrNO3S: C, 43.92; H, 3.07; N, 4.27; S, 9.77. Found: C, 43.92; H, 3.02; N, 4.26; S, 9.84.

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