Au(I)-Catalyzed cycloisomerizations terminated by sp(3) C-H bond insertion.
The gold(I)-catalyzed cycloisomerization of 1,5-enynes and 1,4-allylallenes to tetracyclododecane and tetracyclotridecane derivatives, respectively, is reported. Complexation of the cationic gold(I) complex to either the alkyne or allene moiety induces an intramolecular addition of the alkene, leading to a gold(I)-stabilized carbenoid intermediate. This intermediate undergoes a formal sp(3) C-H insertion to generate the tetracyclic adduct. A series of deuterium labeling experiments showed that the C-H functionalization step proceeds with an inverse kinetic isotope effect.
Horino
Yoshikazu
Y
Graduate School of Science and Engineering, University of Toyama, 3190 Gofuku, Toyama 930-8555, Japan. horino@eng.u-toyama.ac.jp
Yamamoto
Takuya
T
Ueda
Kohki
K
Kuroda
Shigeyasu
S
Toste
F Dean
FD
D000480:Alkynes / Q000737:chemistry*; D000498:Allyl Compounds / Q000737:chemistry*; D001952:Bridged-Ring Compounds / Q000138:chemical synthesis*; D002384:Catalysis; D002414:Cations, Monovalent / Q000737:chemistry; D003500:Cyclization; D006046:Gold / Q000737:chemistry*; D007536:Isomerism
D000480:Alkynes; D000498:Allyl Compounds; D001952:Bridged-Ring Compounds; D002414:Cations, Monovalent; D006046:Gold