Organocopper reagents development

Enantioselective Reactions of Organocopper Reagents. Several methods have been developed for achieving enantioselectivity with organocopper reagents. Chiral auxiliaries can be used for example, oxazolidinone auxiliaries have been utilized in conjugate additions. The outcome of these reactions can be predicted on the basis of steric control of reactant approach, as for other applications of the oxazolidinone auxiliaries. 

The general utility and importance of organocopper reagents in synthesis(lQQ) has instigated considerable research toward developing new... 

Recent theoretical developments such as DFT methods, can of course provide more advanced and precise understanding of these interactions. Hence, Nakamura et al. have recently used computational methods to explain and forecast structure-reactivity relationships in organocopper reagents (Chapt. 10) [28, 43]. 

SN2 -selective reactions between primary allylic substrates and organocopper reagents result in the creation of new chirality in previously achiral molecules, and it is tempting to try to take advantage of this for the development of enantioselective allylic substitution reactions. 

Many of the copper-mediated transformations summarized in the previous sections of this chapter can also be performed efficiently with catalytic amounts of copper salts or reagents. Indeed, some of the copper-catalyzed reactions have been discovered before the development of stoichiometric organocopper reagents. The focus of the last decade has been put on new copper-catalyzed transformations (e.g., conjugate reductions) and in particular on the discovery of chiral copper catalysts for highly enantioselective 1,4-addition and S -substitution reactions of prochiral substrates. 

Organocopper reagents are the most reliable species for conjugate additions and a number of approaches towards chiral cuprates has been developed. The approaches are classified into two categories one is the chiral heterocuprate obtained by treatment with chiral alcohols, amines, sulfonamides, and thiols. The other involves organocopper compounds coordinated by chiral external ligands such as phosphines, sulfides, and oxazolines. 

Many methods have been develop cloalkanones. A clever design incorpoi treatment with organocopper reagents... 

Many methods have been developed for the synthesis of chiral 3-substituted cy-cloaUcanones. A clever design incorporates a neomenthol moiety at the a-position prior to treatment with organocopper reagents. ... 

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