Cross-coupling reactions organozincs

The procedure in Section C is representative of the synthesis of non-natural a-amino acids featuring the palladium cross coupling reaction of a (1-alaninc organozinc derivative with aromatic electrophiles. This methodology has been successfully extended with modifications to both the electrophile and the catalyst as shown in the Table. 

Metal-catalyzed cross-coupling reactions between organozinc derivatives and alkyl halides 405... 

Metal-catalyzed cross-coupling reactions of organozinc derivatives with aryl and vinyl halides 408... 

The cross-coupling reaction of thiomethylpyrimidines 99 with organozinc compounds 100 in the presence of palladium was found to produce pyrimidines 101 in good to excellent yields <00SL905>. 

Recent notable improvements by Knochel and co-workers include iron-catalyzed cross-coupling reactions of various acid chlorides 148 with dialkylzinc reagents (Equation (24))324 as well as the iron-catalyzed arylation of aroyl cyanides 149 with Grignard reagents (Equation (25)).3 5 In the first case Knochel s reaction conditions tolerate ester groups on the organozinc compounds, while in the latter case ester, aryl alkyl ether, cyano, and chloro functionalities on the aromatic moieties are compatibles with the reaction conditions. 

Palladium- or nickel-catalyzed cross-coupling reactions with organozincs and related organometals... 

Mn, the highest TONs were observable with Zn as the countercation. Some of the high TONs observed in the Pd-catalyzed cross-coupling reactions of organozincs are shown in Scheme 2563. 

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