Suzuki-Miyaura coupling scheme

Suzuki-Miyaura coupling (Scheme 13.6). Detailed studies revealed that the transmetalation step is stereospeeifle and this step is likely to be stereochemistry determining. They also believe that the stereoselective transmetalation might oeeur either by a desymmetrization if both boronates are equivalent or by a dynamic kinetic resolution if the geminal boron atoms are not equivalent. 

Scheme 17 Synthesis of C-glycals based on Suzuki-Miyaura coupling/RCM sequence.

An interesting polymer-assisted variant of the Suzuki-reaction was recently disclosed by Vaultier and coworkers (Scheme 17) [43]. Aryl boronic acids can be immobilized on an ion exchange resin. Under Suzuki-Miyaura coupling conditions bisaryl species are released into solution and isolated with minimum purification. The authors also demonstrated that this strategy can be employed for the synthesis of macroheterocycles. 

Scheme 46 Scale-up of a Suzuki-Miyaura coupling in water...

Scheme 50 Suzuki-Miyaura couplings with the POPd2 catalyst...

Scheme 55 Suzuki-Miyaura coupling with glass/polymer-supported catalyst...

Directed remote metalation (DreM) of biaryl amides and O-carbamates, conceptually based on the complex-induced proximity effect (CIPE) [15] provides, especially in view of their link to transition metal-catalyzed cross coupling regimens [16], general and versatile routes to fluorenones (16 —> 15, Scheme 4) [5,17] and biaryl amides (16 —> 17) [18] whose features are overriding Friedel-Crafts reactivity and yield enhancement in comparison to Suzuki-Miyaura coupling routes for highly hindered biaryls, respectively. Additional features of the O-carbamate DreM result is potential further DoM of 17 with appropriate phenol protection and cyclization to dibenzopyranones [18]. 

The carbamate substituted DHP derivative 647 has been deprotonated with f-BuLi in THF at — 78 °C to give the vinyllithium 648950 (Scheme 169). This reagent has been functionalized with a variety of electrophiles in good yields. The iodinated derivative 649 (X = I) underwent Suzuki-Miyaura couplings with arylboronic acids to afford the corresponding a-arylated DHPs. 

A rapid and efficient Suzuki-Miyaura coupling protocol utilising fibrous PS-based palladium catalysts (FibreCaF ) and microwave irradiation has been reported by Wang and Sauer (Scheme 8). The biaryl motif 26, formed in this reaction, is an important pharmacophore in many biologically active compounds. Each reaction... 

Scheme 12 Reactivity of 43 in the Suzuki-Miyaura coupling of tetra-ortho-substituted biaryls...

In 2010, Kantchev and co-workers developed a series of palladacycle complexes of the formula [Pd(NHC)(palladacycle)] and evaluated their activity in Suzuki-Miyaura coupling. Complex 84 was found to be the most active pre-catalyst, efficiently forming a number of C—C bonds, including sp —sp, sp —sp, sp —sp, and sp —sp, in good-to-excellent yield (Scheme 19). The high reactivity of complex 84 in... 

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