Microwave-assisted reactions Suzuki-Miyaura reaction

Lepine and Zhu accomplished total synthesis featuring judicious use of the PTC 1-catalyzed asymmetric alkylation of Schiff base 1 and a microwave-assisted intramolecular Suzuki-Miyaura reaction for the formation of... 

Lepine R, Zhu J. Microwave-assisted intramolecular Suzuki—Miyaura reaction to macrocycle, a concise as3mimetric total synthesis of biphenomycin B. Org. Lett. 2005 7 (14) 2981-2984. 

A facile synthesis of some new substituted aryl and heteroarylflavones by thermal and microwave-assisted Suzuki-Miyaura coupling reaction was also carried out (Joshi and Hatim, 2012). 

E. Van der Eycken et al. explored a microwave-assisted Suzuki-Miyaura reaction to generate structural analogues of the apogalanthamine family... 

It is noteworthy that the microwave-assisted Suzuki-Miyaura reactions were found to be far superior to the reactions under conventional heating, as can be demonstrated by yield improvements from 22% to 84% in the case of cross-coupling of PEA derivatives. Microwave-irradiation also provided smooth conversions in water as the sole solvent. 

The time consuming chromatographical purification of heterocycles 28 and 29 slowed down the rate of library production. A phase separation using fluorous chemistry was employed by Zhang and Lu to address the workup and purification of fused 3-aminoimidazo[ l,2-a]pyridines (such as 30) [54]. Thus, attachment of a perfluorooctanesulfonyl tag to aldehydes and subsequent Ugi three-component microwave-assisted condensations with 2-aminopyridines and isocyanides furnished the desired heterocycles 30, which were conveniently isolated by fluorous solid-phase extraction. The fluorous tag could be subsequently used as an activating group in the post-condensation modifications, such as Suzuki-Miyaura cross-coupling reactions. 

Dawood KM (2007) Microwave-assisted Suzuki-Miyaura and Heck-Mizoroki crosscoupling reactions of aryl chlorides and bromides in water using stable benzothiazole-based palladium(ll) precatalysts. Tetrahedron 63 9642-9651... 

Unprotected 4-heteroaryl phenylalanines have been prepared by microwave-assisted Suzuki-Miyaura reactions. Amino adds containing the biaryl motif have several interesting applications in medicinal chemistry and this method enabled their synthesis without protection of the amino acid. Optically pure boronic acids could be used without racemization (Scheme 15.16) [49]. 

Microwave-assisted Suzuki-Miyaura cross-coupling reaction has been used for the generation of aza-analogs of the natural product Steganacin (Chapman and Thompson, 2007). It was reported that the application of microwave irradiation was highly beneficial for the biaryl coupling of electronically rich aryl bromides with some substituted o-formylphenylboronic acids (Beryozkina et al., 2006). 

A microwave-assisted tandem Ir-catalyzed C-H boronylation/Pd-catalyzed Suzuki-Miyaura cross-coupling reaction has been reported (Harrisson et al., 2009). This includes the synthesis of arylboronic acids, direct boronylation of arenes and alkanes, which provides access to synthetically useful compounds without relying on the accessibility of aryl or alkyl halides. They developed an elegant methodology for the direct C-H boronylation using a pinacoldiborane dimer under microwave irradiation at 80°C for 5-60 min. 

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