Suzuki nickel-catalyzed

K. Tamao, S. Kodama, I. Nakajima, M. Kumada, A. Minato, and K. Suzuki, Nickel-phosphine complex-catalyzed Grignard coupling — II Grignard coupling of heterocyclic compounds, Tetrahedron, 38 3347-3354, 1982. 

Other successful examples of catalysts containing NHC ligands are found in palladium- and nickel-catalyzed carbon-carbon bond formations. The catalyst development with these metals has focused in particular on Heck-type reactions, especially the Mizoroki-Heck reaction itself [Eq. (42)] and various cross coupling reactions [Eq. (43)], e.g., the Suzuki-Miyaura reaction ([M] = and the Kumada-Corriu reaction ([M] = MgBr). " Related reactions like the Sonogashira coupling [Eq. (44)]326-329 Buchwald-... 

Fig. 2 Nickel-catalyzed alkyl-alkyl and alkyl-aryl Suzuki-Miyaura coupling reactions...

For the synthesis of the non-diene analogue 65, which bears a benzyl group in the terminal position (Scheme 17), 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) cleavage of the p-methoxybenzyl (PMB) ether at the C15-position did not proceed in the presence of the benzyl moiety (oxidation of the methylene in allylic-benzylic-position in C23-position). Therefore, we inverted the order of the first two steps (1) DDQ deprotection on 44 and (2) nickel-catalyzed cross-coupling reaction performed on a free primary alcohol in C15 position. After this minor modification, completion of the synthesis followed the established route Suzuki-Miyaura crosscoupling reaction between alkyl iodide 73 (via its trialkylboronate species) and vinyl iodide 60 to yield 74 selective carbamate installation and final deprotection to afford DDM analogue 65. 

Example 5, Nickel-catalyzed Suzuki-Miyaura coupling in green solvents ... 

More than 20 years later, Miyaura reported the first nickel-catalyzed Suzuki coupling of aryl chlorides. Initially, n-BuLi was used to reduce nickel(II) to nickel(O) (Equation 2.3) [11]. 

For other examples of nickel-catalyzed Suzuki couplings of aryl tosylates, see ... 

Chatani et al. [137] have reported on nickel-catalyzed Suzuki-Miyaura reactions with aryl fluorides as the cyclometalation substrates, as shown in Eqs. (8.27) and (8.28). 

Other related nickel-catalyzed Negishi, Hiyama, and Suzuki-Miyaura reactions of unactivated secondary alkyl halides, radical intermediates may be involved [140, 142-144],... 

K. Ogata, H. Murayama, J. Sugasawa, N. Suzuki, S.-I. Fukuzawa, J. Am. Chem. Soc. 2009,131, 3176-3177. Nickel-catalyzed highly regio- and stereoselective cross-trimerization between triisopropylsilylacetylene and internal alkynes leading to l,3-diene-5-ynes. 

Along with their work on the nickel-catalyzed Suzuki-Miyaura coupling of neopentylglycol boronic esters, Percec and coworkers examined the speed of transesterification of a cyclic arylboronic ester with a diol under anhydrous conditions. In both assays in Scheme 3.2, some transesterification had taken place after 10 h (equilibrium was not reached). This result shows that transesterification of cyclic boronic esters is always possible, even starting from pinacol esters. This should be kept in mind when considering reactions in the presence of alcohol solvents and water. 

Baghbanzadeh M, Pilger C, Kappe CO (2011) Rapid nickel-catalyzed suzuki-miyaura crosscouplings of aryl carbamates and sulfamates utilizing microwave heating. J Oig Chem 76(5) 1507 1510. doi 10.102 l/jol024464... 

The nickel-catalyzed Suzuki-Miyaura-type C-O bond arylation has been successfully applied to steroidal architecture (Scheme 4). A hydroxyl moiety in estrone can readily be substituted by an array of aryl groups under nickel catalysis via conversion into pivalate instead of the typically used triflate [38]. The carbonyl moiety in estrone also serves as a suitable precursor for an alkenyl C-O electrophile. Treatment of estrone with 2-propenyl acetate affords the compounds bearing two acetate groups, both of which are potentially reactive toward nickel-catalyzed cross-coupling. However, selective arylation took place at the alkenyl position, and... 

Directed orf/to-metalation (DoM) chemistry [81] further reinforces the versatility of nickel-catalyzed C-O bond activation reactions. Based on the strong accelerating and orf/to-directing effect of carbamate functionality in the base-induced deprotonation of arenes, an array of electrophiles can be introduced at the ortho position of aryl carbamates. For instance, DoM of dicarbamate, followed by 1,2-addition to a,(3-unsaturated aldehyde and intramolecular cyclization, furnishes the 2//-chromene derivative (Scheme 8) [82]. The carbamate director can finally be arylated under a nickel-catalyzed Suzuki-Miyaura-type reaction [47]. 

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