Heteroaromatic compounds, Suzuki coupling

Costanzo et al. <2002MI87> published the synthesis of the furyl-substituted pyrazolo[3,2-f][l,2,4]triazine derivative 146 by Suzuki coupling of the iodo compound 145 with 2-furylboronic acid. The yield was found to be moderate (38%). It may be important to mention that these authors also tried to transform 145 to a heteroaromatic boronic acid and to carry out cross-coupling of this compound with 3-bromofuran. Unfortunately, however, this approach failed and only homo-coupling occurred. 

The Suzuki coupling reaction is a powerful tool for the construction of biaryl compounds and their homologues, which are key structural elements of various natural products, polymers, and compounds of medicinal interest. Aryl boronic acids and their esters are the usual substrates in reactions with aryl or heteroaromatic halides and... 

Later in 2010, Kantchev and co-workers examined palladacycle 84 in Suzuki-Miyaura coupling and found it to be a highly active catalyst, forming a variety of C-C bonds, including the formation of (poly)heteroaromatic compounds at elevated temperatures (Scheme 19, see above). Also in 2010, Lee and co-workers developed amido-A-imidazolium salt 87 and evaluated it in the formation of heteroaromatic... 

Satoh, M. Miyaura, N. Suzuki, A. 1987. Palladium catalyzed cross-coupling reaction of (1-ethoxy-l-alken-2-yl)boranes with ortho-functionalized iodoarenes. A novel and convenient synthesis of benzo fused heteroaromatic compounds. Synthesis 373-377. 

A ramification of the DreM strategy in an unusual heteroaromatic framework is illustrated in the synthesis of the previously unknown triazadibenzo[cd,/]azulen-7(6H)-one 75 in which the imidazopyridines 70 and 71 are coupled by a Suzuki-Miyaura reaction with the DoM-derived boronic add 72 to give 73 and 74, respectively (Scheme 14.18). Compound 74 undergoes DreM cyclization on treatment with LiTMP to give the potentially bioactive 75 in modest yields [126]. 

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