Cyclic Heck Reactions, Noteworthy Variations

Although this chapter focuses its attention on cyclic carbopalladation reactions other than the cyclic Heck reaction, it might be useful to discuss here the following variants of the cyclic Heck reaction. For the vast topic of the cyclic Heck reaction including those variants discussed below, the reader are referred to the following chapters of the Handbook of Organopalladium Chemistry for Organic Synthesis [40]. 

One significant consequence of the formation of allylpalladium derivatives is that it represents an escape from the Heck reaction manifold permitting a wide variety of non-Heck processes via carbopalladation, which is the focal point of the rest of this chapter. 

Cyclic Carbopalladation Terminated by Processes Other than /TDehydropalladation 

Ring size Substrate Cyclic carbopalladation Cyclic acylpalladation 

Synthesis of benzene, cyclohexadiene, along with other related six-membered rings via circular trimerization of three C = C and/or C = C bonds has long attracted attention of the synthetic chemists. In most cases, it is thermo- 

4-HOC6H4.3,5-MeaC6H3 C32CO3, Eton (a-PhCH-CH. (a- BuCH=C 

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