Chain-Walking Strategy for Organic Synthesis: Catalytic Cycloisomerization of 1,n-Dienes
摘要:
The catalytic construction of carbon-carbon bonds in small organic molecules via chain walking is described. Catalytic cycloisomerization of 1,n-dienes via chain walking was achieved using a palladium-1,10-phenanthroline catalyst to form five-membered-ring products. By means of a cycloisomerization/hydrogenation protocol, 1,7- to 1,14-dienes were selectively converted to bicyclo[4.3.0]nonane derivatives. The use of chain walking provides a new method in organic synthesis to functionalize unreactive carbon-hydrogen bonds by letting the catalyst look for preferable bond-forming sites by moving around on the substrate.
Metal‐Catalyzed Sequential Formation of Distant Bonds in Organic Molecules: Palladium‐Catalyzed Hydrosilylation/Cyclization of 1,
<i>n</i>
‐Dienes by Chain Walking
Sequential formation of distant bonds in organic molecules was achieved for the palladium‐catalyzed hydrosilylation/cyclization of various 1,n‐dienes by chain walking of the metal catalyst. The reaction was applicable to various 1,n‐dienes, including a 1,13‐diene, to form a cyclopentane ring as well as a carbon–silicon bond at a remote site. The use of “nondissociative” chain walking provides a fascinating