Réaction #425724

Équation de réaction

acetic acid

4-bromobenzaldehyde

3-buten-1-ol

hydrobromic acid

→

title compound

Rendement 57.8%

4-bromo-2-(4-bromophenyl)tetrahydro-2H-pyran

Rendement 57.8%

Solvants

dichloromethane

Conditions de réaction

Traitement

1. 1
   AutreReaction
2. 2
   Autrewas quenched by aqueous sodium bicarbonate
3. 3
   Extractionextracted with ethyl acetate
4. 4
   Lavagewashed with brine
5. 5
   Séchagedried over sodium sulfate
6. 6
   Filtrationfiltered
7. 7
   Concentrationconcentrated
8. 8
   AutreThe residue was purified by silica gel chromatography

Mode opératoire

To a solution of 4-bromobenzaldehyde (1.00 g, 5.41 mmol) and 3-buten-1-ol (800 mg, 10.8 mmol) in dichloromethane (20 mL) at room temperature was added zinc (II) bromide (25 mg, 0.11 mmol) followed by 33% hydrobromic acid (2.4 g) in acetic acid (4.9 g, 81 mmol) and stirred at room temperature for 5 hours. Reaction was quenched by aqueous sodium bicarbonate, then extracted with ethyl acetate, washed with brine, dried over sodium sulfate, filtered and concentrated. The residue was purified by silica gel chromatography to give the title compound (1.00 g) which contained some of 4-bromobenzaldehyde 1H NMR (400 MHz, CDCl3) δ ppm 7.49 (d, 2H) 7.24 (d, 2H) 5.19 (dd, 1H) 4.25 (m, 1H) 4.12 (m, 1H) 3.60 (m, 1H) 2.75 (m, 1H) 2.68 (m, 1H) 2.11 (m, 2H).

Source