Formation of Five-Membered Cycles

This is not a comprehensive listing, and other substructures leading to five-membered cycles will be presented at the end of this section. 

A recent procedure describes a one-pot, two-step mutlicomponent reaction of bromoani-lines 13, aldehydes 14, acids 15 and isocyanides 16 yielding polysubstituted indoles 18 [34]. It is based on a Ugi four-component reaction yielding the precursor 17 for the in situ performed classical intramolecular Mizoroki-Heck reaction, thereby providing a facile access to highly substituted dihydro-indoles, l//-indoles and l//-indole-2-carboxyhc 

A huge number of similar examples preparing indoles or related derivatives via intramolecular Mizoroki-Heck reactions can be found in the literature [35-39] enumerating them all would be impossible. 

As a lot of natural products contain fused A-heterocycles, intramolecular Mizoroki-Heck reactions have also been extensively used in total synthesis. Magallanesine (28) [48], an 

Aside from these most frequently met substrate types leading to 5-exo-cyclizations discussed above, there are several examples of further substructures that also give rise to intramolecular Mizoroki-Heck reactions via 5-cxo-cyclizations. 

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