Diiodomethane → 1-Bromo-4-iodomethanesulfonyl-benzene

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A stirred mixture of 4-bromo-benzenesulfonyl chloride (5.12 g, 20 mmol), sodium sulfite (4.69 g, 37.3 mmol) and sodium bicarbonate (3.07 g, 36.6 mmol) in water (20 mL) is heated at 100° C. for 1 h. The crude sodium sulfinate solution is allowed to cool for 30 min and then treated with diiodomethane (25 mL) and tetra-N-butyl ammonium bromide (0.65 g, 2.0 mmol). The resulting mixture is heated at 75° C. overnight. The organic layer was separated. The aqueous solution was extracted with CH2Cl2 (×2). The combined organics were washed with water and brine, and dried over anhydrous MgSO4. The filtration through Celite-silica gel pad and concentration in vacuo gave light yellow liquid residue. Et2O/hexane (1:1) was added to the residue and the mixture was stirred to make homogenous and sit at 0 C for 20 min. The product was crushed out of the solution, filtered and washed with Et2O/hexanes. 1H NMR (300 MHz, CDCl3) 7.83 (d, 2H), 7.75 (d, 2H), 4.48 (s, 2H).

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