Enantioselective nickel-catalysed

Enantioselective Nickel-Catalysed Transformations By H lfene Pellissier H l ne Pellissier, 2016... 

In the last decade, several excellent results were also published in the area of enantioselective nickel-catalysed Diels-Alder cycloadditions. Among them, the reactions of cyclopentadiene with 3-alkenoyloxazolidin-2-ones induced by (i )-BINIM-2QN provided cycloadducts in up to >99% yield, >98% de, and 96% ee. Another excellent result was achieved by using a chiral iV,iV -oxide-derived nickel catalyst in Diels-Alder cycloadditions of 3-vinylindoles with methyleneindolinones for the construction of chiral spiro[carbazole-oxindoles] in up to 97% yield, >98% de, and 98% ee. Moreover, the use of the chiral DBFOX-Ph ligand has allowed an inverse-electron-demand Diels-Alder reaction of a range of Af-sulfonyl-l-azadienes with vinyl ethers to be achieved, providing highly functionalised piperidines in up to 75% yield, 96% de, and 92% ee. 

Scheme 2.1 First enantioselective nickel-catalysed conjugate additions reported by Soai et aL in 1988-1989.

Among the most successful catal)rtic systems employed in enantioselective nickel-catalysed Michael additions of nucleophiles to nitroalkenes is that developed by Evans and Seidel in 2005, which allowed enantioselectivities of up to 95% ee to be achieved in the enantioselective conjugate additions of 1,3-dicarbonyl compounds to nitroalkenes (Scheme 2.3). Products resulting... 

In 2012, Wu et al reported a practical large-scale preparation of the antidepressant drug (i )-rolipram from isovanilline, the key step of which was an enantioselective nickel-catalysed conjugate addition of diethyl malonate to a functionalised nitroalkene. Using only 1 mol% of catalyst the reac-... 

Very recently, the same authors reported the first catalytic asymmetric approach to octahydroindolones, which was based on the enantioselective nickel-catalysed conjugate addition of tert-butyl malonate to a nitrodi-enyne. In the presence of a chiral catalyst generated in situ from NiBr2 and chiral diamine 7, the 1,4-conjugate addition proceeded smoothly to provide the corresponding enantioenriched 1,3-enyne in 91% yield and with 93% ee, as shown in Scheme 2.12. It was worth noting that 1,6- or 1,8-addition was not observed. The formed functionalised product could be further decarbox-ylated and then cyclised into the corresponding cyclohexanone, which was... 

In 2014, Hamashima and Kan reported the practical total syntheses of acro-melic acids A and B, having potent neuro-excitatory activity, which were based on enantioselective nickel-catalysed asymmetric conjugate additions of a-keto esters to nitroalkenes. Indeed, the key steps of the syntheses of these natural... 

Inspired by their previous work dealing with enantioselective conjugate addition of t-butyl acetoacetate to crotonoylthiazolidinethione catalysed by a preformed nickel catalyst from/>-To 1-BINAP ligand 30, and by those of Kane-masa on enantioselective nickel-catalysed additions of thiols and 1,3-dike-tones to unsaturated acylpyrazoles and oxazolidinones with a chiral amine ligand, Evans et al. investigated the scope of enantioselective Michael... 

Enantioselective Nickel-Catalysed Cross-Coupling Reactions... 

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