Hydration of Terminal Alkynes Catalyzed by Water-Soluble Cobalt Porphyrin Complexes

Water-soluble cobalt­(III) porphyrin complexes were found to promote the hydration of terminal alkynes to give methyl ketones. The alkyne hydration proceeded in good to excellent yield with 0.1 to 2 mol % cobalt catalyst <b>1</b> and was compatible with the presence of acid/base- or redox-sensitive functional groups such as alkyl silyl ethers; allyl ethers; trityl ethers; benzyl ethers; carboxylic esters; boronic esters; carboxamides; nitriles; and nitro, iodo, and acetal groups. Some of the alkyne substrates tested here are otherwise difficult to hydrate. The alkyne hydration can be performed on a gram scale, and the catalyst can be recovered by aqueous workup

Hydration of Terminal Alkynes Catalyzed by Water-Soluble Cobalt Porphyrin Complexes

Water-soluble cobalt­(III) porphyrin complexes were found to promote the hydration of terminal alkynes to give methyl ketones. The alkyne hydration proceeded in good to excellent yield with 0.1 to 2 mol % cobalt catalyst <b>1</b> and was compatible with the presence of acid/base- or redox-sensitive functional groups such as alkyl silyl ethers; allyl ethers; trityl ethers; benzyl ethers; carboxylic esters; boronic esters; carboxamides; nitriles; and nitro, iodo, and acetal groups. Some of the alkyne substrates tested here are otherwise difficult to hydrate. The alkyne hydration can be performed on a gram scale, and the catalyst can be recovered by aqueous workup

N‑Methylation of Amines with Methanol at Room Temperature

N-Methylation of amines with methanol proceeds at room temperature in the presence of a silver-loaded titanium dioxide (Ag/TiO₂) photocatalyst under UV–vis light irradiation. This method allows facile synthesis/isolation of <i>N</i>-methylamines bearing various functional groups including <i>N</i>-benzyl, <i>N</i>-allyl, <i>N</i>-Boc, hydroxyl, ether, acetal, carboxamide, formamide, and olefin groups