Synthesis of Aldimines from Alcohols and Amines with Ru(OH)x/TiO2

Significance TiO 2 -supported ruthenium hydroxides (Ru(OH) x /TiO 2 ) catalyzed the oxidative condensation of primary alcohols 1 with primary amines 2 under 1 atm of O 2 to give the corresponding aldimines 3 in 62-98% yield (11 examples). The catalyst was recovered by simple filtration and reused without significant loss of catalytic performance for the formation of 3a (reuse: 94%).