Intramolecular Hydroamination of Alkynes Catalyzed by Pd(PPh3)4/Triphenylphosphine under Neutral Conditions
摘要:
The intramolecular hydroamination of alkynes tethered with amino group 1 in the presence of catalytic amounts of Pd(PPh3)(4) and PPh3 in benzene at 100 degrees C proceeded smoothly without the use of any additional acid source to afford five and six-membered nitrogen heterocycles 2 in good to excellent yields. A compulsory addition of carboxylic acid as a cocatalyst was not needed, and the reaction could be carried out under essentially neutral conditions.