Pd‐Catalyzed Domino Arylation/CH Activation for the Synthesis of Acenaphthylenes.

Abstract

Pd-Catalyzed Domino Arylation/CH Activation for the Synthesis of Acenaphthylenes. -The cyclization of the aromatic alkynes (IIIa)-(IIIc) gives the acenaphthylenes (IVa)-(IVc) in good yields without the need for protection of the hydroxy group. Aliphatic alkynes such as (IIId) can also be used, albeit with lower yield. Sterically hindered alkynes such as (IIIe) or the tert-butyl derivative (V) do not react or undergo only the first C-C bond formation step. -(TIETZE*, L. F.; LOTZ, F.; Eur.

Total Synthesis of Cyclopiamide A Using Palladium-Catalyzed Domino Cyclization

“…Under several of the evaluated sets of conditions, desired product 1 was not produced within an unidentifiable mixture of by-products. A literature search for similar domino intramolecular carbopalladation systems ending with the C-H activation of alkyne substrates revealed that an internal alkyne is essential for successful transformation [ 17 , 18 , 19 , 20 , 21 , 22 ]. Therefore, the terminal alkyne group of 2 was protected with a silyl group using LiHMDS and TBDMSCl to obtain the internal alkyne 10 in 80% yield.…”