Direct Asymmetric Arylation of Imines

Abstract

The Friedel-Crafts reaction represents one of the most efficient tools for the formation of carbon-carbon bonds and direct derivatization of aromatic compounds. Asymmetric arylation of imines involving Friedel-Crafts reaction has received much interest recently. The present review summarizes the works on the asymmetric arylation of imines by different approaches including Friedel-Crafts reaction and their development to date. The review is divided into three main sections: addition reaction of arenes to imines in the presence of chiral catalysts; addition reaction of arenes to imines containing chiral tails and asymmetric coupling reaction of aryl boronic acids and imines. 4.2. Palladium Catalysts with Chiral Ligands 4.3. Nickel Catalysts with Chiral Ligands 5. Conclusions

Strategies for the Catalytic Enantioselective Synthesis of α-Trifluoromethyl Amines

“…The addition of several classes of carbon-based nucleophiles to trifluoromethyl imines has been extensively explored for the stereoselective synthesis of α-trifluoromethyl amines. Many of these nucleophiles have been utilized in conjunction with chiral auxiliary strategies in addition to catalytic enantioselective technologies, including a number of organometallic reagents, alkynes, allyl nucleophiles, enolate-type nucleophiles, and cyanide. , Both aldimine and ketimine electrophiles have been employed, giving rise to α-secondary and α-tertiary amines. Therefore, a broad range of chemical space has been covered by this inclusive category of transformations.…”

“…With a growing need for single-enantiomer α-CF 3 amines, a number of stereoselective methods for their construction have emerged . The majority of these approaches have relied on diastereoselective transformations with chiral reagents, often taking one of two forms: (1) conjugate addition of chiral amines to β-CF 3 -substituted Michael acceptors or (2) nucleophilic additions to imines bearing a chiral auxiliary attached at the nitrogen atom …”

Direct Asymmetric Addition of Heteroatom Nucleophiles to Imines

“…[1][2][3] The reactions of asymmetric addition of carbon nucleophiles with the formation of the CÀ C bond are quite numerous and are described in detail in the literature. In particular, we have previously published works on the attachment of arene nucleophiles to imines, [4] as well as to the C=N bond of electrondeficient heteroaromatic compounds. [5] To the best of our knowledge, there is no such review in literature where the formation of new CÀ X bonds during the interaction of non-carbon nucleophiles with imines has been discussed including the asymmetric addition of non-carbon nucleophiles to imines.…”

Catalytic Enantioselective Strecker Reaction of Isatin-Derived N-Unsubstituted Ketimines

“…Catalytic enantioselective nucleophilic addition to ketimines is an effective means of synthesizing enantioenriched α-tetrasubstituted amines, which are useful building blocks for nitrogen-containing organic molecules such as biologically active compounds and pharmaceuticals . Most of the reported reactions are facilitated by N-protected ketimines (Scheme , upper equation), however, and thus often require protection/deprotection steps for the amino group in the reaction sequence before derivatization on the nitrogen atom, which limits the synthetic utility of the protocol, especially with respect to the green synthesis of amines.…”