Palladium-catalyzed tandem cyclization/Suzuki coupling of 1,6-enynes: reaction scope and mechanism.
A palldium(0)-catalyzed tandem cyclization/Suzuki coupling reaction of various 1,6-enyne substrates was developed. This Pd-catalyzed enyne cyclization reaction represents a new process for the synthesis of stereodefined alpha-arylmethylene-gamma-butyrolactones, lactams, multifunctional tetrahydrofurans, pyrrolidines, and cyclopentanes. The mechanism of the reaction was studied by the employment of different enyne isomers and boronic acids; a pi-allyl palladium intermediate was suggested to explain the formation of the cyclic products. The stereochemistry of this reaction can be well explained by a chairlike transition state.
Zhu
Gangguo
G
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, China.
Tong
Xiaofeng
X
Cheng
Jiang
J
Sun
Yanhui
Y
Li
Dao
D
Zhang
Zhaoguo
Z
D000480:Alkynes / Q000138:chemical synthesis*; D002384:Catalysis; D003500:Cyclization; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*
D000480:Alkynes; D010165:Palladium