Pd(II)-catalyzed enantioselective oxidative tandem cyclization reactions. Synthesis of indolines through C-N and C-C bond formation.
We have developed an efficient Pd(II)-catalyzed enantioselective oxidative tandem cyclization strategy using molecular oxygen as a green oxidant for the double 5-exo-trig cyclizations of N-(2-allylaryl) amides to afford a variety of indolines in good yields without the formation of undesired monocyclization products. By employing Pd(TFA)2/(-)-sparteine as the chiral catalyst, we obtained tandem cyclization products with high enantioselectivity (up to 91% ee).
Yip
Kai-Tai
KT
Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, PR China.
Yang
Min
M
Law
Ka-Lun
KL
Zhu
Nian-Yong
NY
Yang
Dan
D
D002384:Catalysis; D003500:Cyclization; D007211:Indoles / Q000138:chemical synthesis*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D010165:Palladium / Q000737:chemistry; D013034:Sparteine / Q000737:chemistry; D013237:Stereoisomerism
D007211:Indoles; D013034:Sparteine; D010165:Palladium; C057812:indoline; D010100:Oxygen