Suzuki side-reactions

H. Suzuki, Side Reactions in Aromatic Nitration, Synthesis 1977, 217-238. 

Suzuki-Miyaura as well as moderate activity in the Stille reaction ([M] = SnRa) were observed. In contrast to bis(NHC) complexes, inactivity in the Sonogashira reaction was due to increased activity in the homocoupling of alkynes [Eq. (47)], an undesired side reaction. 

Other Pd cross-coupling reactions such as Heck [52] and Suzuki [53] reactions have also been used for macrocyclizations. The main drawback for Pd catalyzed macrocylization is the yield, that is often somewhat disappointing if compared with other established methods. Also, the introduction of the required coupling components (e.g., trialkyltin group, vinylic iodide) can be difficult in some compounds. In other cases, Pd-catalyzed side reactions such as double bond migration or allylic activation can occur. 

For monographs, see Olah Malhotra, Narang Nitration Methods and Mechanisms-, VCH New York, 1989 Schofield Aromatic Nitration Cambridge University Press Cambridge, 1980 Hoggett Moodie Penton Schofield. Ref. 30. For reviews, see Weaver, in Feuer Chemistry of the Nitro and Nitroso Groups, pt. 2 Wiley New York. 1970. pp. 1-48 de la Mare Ridd, Ref. 59, pp. 48-93. See also Ref. 1. For a review of side reactions, see Suzuki Synthesis 1977, 217-238. 

For side reactions in aromatic nitration see H. Suzuki, Synthesis, 1977, 217. 

Although side reactions associated with the supporting phospine ligands do not greatly affect small molecule couplings, they can affect polymerizations dramatically. The effect of one of these side reactions will be discussed. A general catalytic cycle for the Suzuki coupling process is shown in Scheme 1. 

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