تفاعل #1772053

معادلة التفاعل

7-bromo-4H-chromen-4-one

diisobutylaluminium hydride

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7-bromochroman-4-one

المردود 69.0%

المذيبات

THF

ظروف التفاعل

المعالجة

1. 1
   أخرىquenched with a SiO2 (52 g)/water (52 mL) suspension
2. 2
   درجة الحرارةto warm to 0° C
3. 3
   ترشيحThe solution was filtered
4. 4
   غسيلthe SiO2 washed with EtOAc
5. 5
   تركيزthe combined filtrate was concentrated to dryness
6. 6
   workup.DISSOLUTIONThe residue was dissolved in CHCl3 (400 mL)
7. 7
   غسيلwashed with 1N NaOH (300 mL)
8. 8
   تجفيفdried over Na2SO4
9. 9
   تركيزconcentrated
10. 10
    أخرىPurification by chromatography on SiO2 (60-120 mesh) EtOAc/Pet ether (gradient elution 0-15%)

الإجراء التجريبي

A solution of 7-bromo-4H-chromen-4-one (26 g, 116 mmol) in dry THF (500 mL) under nitrogen for 1 hr, cooled to −80° C., and 173 mL of diisobutylaluminium hydride (2M in Toluene) was added over 30 minutes. The reaction was stirred at the same temperature for 30 min, quenched with a SiO2 (52 g)/water (52 mL) suspension, and allowed to warm to 0° C. The solution was filtered, the SiO2 washed with EtOAc, and the combined filtrate was concentrated to dryness. The residue was dissolved in CHCl3 (400 mL), washed with 1N NaOH (300 mL), dried over Na2SO4 and concentrated. Purification by chromatography on SiO2 (60-120 mesh) EtOAc/Pet ether (gradient elution 0-15%) afforded 7-bromochroman-4-one 18.1 g (69%) a pale yellow solid. LCMS 229.0 (M+2H); 1H NMR (DMSO-d6) 7.64-7.67 (d, 1H), 7.32 (s, 1H), 7.22-7.25 (d, 1H), 4.53-4.57 (t, 2H), 2.76-2.80 (t, 2H).

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