Multi-coupling reagents

Selective palladium(0)-catalyzed arylation can be performed with aryl iodides bearing a triflate function using an appropriate palladium catalyst. Under these conditions, aromatic iodotriflates like 59 can play the role of multi-coupling reagents [88]. Thus, the reaction of 59 with a functional arylzinc bromide provides the functionalized biphenyl triflate 60 (see Section 9.6.13 Scheme 9-48) [89]. 

Heinze and Burton reported the first practical synthesis of a,/S,/S-trifluorostyrenes via the palladium-catalyzed coupling of the trifluorovinylzinc reagent with aryl iodides29 (equation 48). This methodology avoided the low temperatures in the earlier tetrafluo-roethylene route47, avoided side products (stilbenes) and/or multi-step procedures that plagued earlier reports of this important olefin29. 

B. Typical multi-functional coupling strategy and reagents ... 

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