Reusable cobalt-phthalocyanine in water: efficient catalytic aerobic oxidative coupling of thiols to construct S–N/S–S bonds

A new aerobic oxidative coupling of thiols in water to construct sulfenamides or disulfides was developed, utilizing cobalt(ii)phthalocyanine-tetra-sodium sulfonate as the catalyst and O2 as the oxidant. The mother liquor could be recycled up to 20 times with negligible loss of activity and only a minor decrease of product yield.