Dimethyl Disulfide → 3-Methylthio-4-hydroxy-5-benzyloxybenzaldehyde

Participants

Reaction Conditions

Reaction Steps

In an alternative procedure a 50-L flask equipped with a mechanical stirrer was charged with 3-bromo-4-hydroxy-5-benzyloxybenzaldehyde (1.332 kg, 4.34 mol), Copper powder (1.068 kg, 16.82 mol), dimethyldisulfide (1.068 kg, 11.36 mol) and pyridine (23 L). The mixture was heated at 95° C. overnight with gentle stirring, filtered, and the filtered cake was washed with dichloromethane (30 L). The pyridine filtrate was distilled off to leave a black residue, from which the product was extracted with the dichloromethane washes. The combined organic extracts were washed with 2N HCl until it became light brown and the acidic aqueous layer was clear. The organic layer was dried (MgSO4), filtered, and the filtrate was evaporated to dryness. Crystallization from dichloromethane-hexane gave the title compound (900 g, 76%): mp 117°-119° C.; NMR (CDCl3) δ 2.50 (s, SCH3), 5.20 (s, OCH2Ar), 6.72 (s, OH), 7.34-7.46 (m, ArH), 9.78 (s, ArCHO)

Provenance & Evidence