Heck sp-cascade

In 2007, Hitce and Baudoin reported an elegant procedure to synthesize four-membered benzocarbocycles via a palladium-catalyzed three-step one-pot cascade reaction [14a] (Scheme 6.6). In this work, Baudoin et al. efficiently combined C(sp )—H activation [14b] of 32 with an unusual 4-exo-trig Heck cyclization, affording exo-methylenebenzocyclobutene 33. Finally, ( )-trisubstituted olefins 34 were constructed through a Heck arylation. 

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