Methyl iodide → 2,3,4,5-tetramethoxytoluene

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Syper, L. et al., Tetrahedron 36:123 (1980). To a solution of 1,2,3,4-tetramethoxybenzene 12 (4.0 g, 20.2 mmol) and TMEDA (6 mL, 38.0 mmol) in hexanes (44 mL) and THF (80 mL) at 0° C. under Ar, n-BuLi in hexane (1.6 M, 25.6 mmol) was added dropwise over a 10 min period and the reaction stirred for 30 min at 0° C. under Ar. Subsequent to dropwise addition of CH3I (20 mL, 160 mmol) over an 8 min period, the reaction was stirred for 3 h at 0° C. under Ar and then quenched by addition of aqueous NH4Cl and ether (20 mL). The organic layer was sequentially washed with concentrated NH4OH, water, and brine. Drying and concentration of the organic layer was followed by purification of the residue by flash chromatography (hexanes, hexanes/EtOAc, 19:1, v/v) to afford 13 as a clear oil (3.6 g, 83%). 1H NMR (CDCl3): δ6.45 (s, 1 H), 3.93 (s, 3 H), 3.87 (s, 3 H), 3.82 (s, 3 H), 3.79 (s, 3 H), 2.23 (s, 3 H). 13C NMR (CDCl3): δ149.0, 146.9, 145.3, 140.7, 125.7, 108.2, 61.0, 60.9, 60.5, 55.9, 15.7.

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