Synthesis of novel 9-aryl and heteroarylpurine derivatives via copper mediated coupling reaction

Advances in Carbon–Element Bond Construction under Chan–Lam Cross-Coupling Conditions: A Second Decade

Copper-mediated carbon–heteroatom bond-forming reactions involving a wide range of substrates have been in the spotlight for many organic chemists. This review highlights developments between 2010 and 2019 in both stoichiometric and catalytic copper-mediated reactions, and also examples of nickel-mediated reactions, under modified Chan–Lam cross-coupling conditions using various nucleophiles; examples include chemo- and regioselective N-arylations or O-arylations. The utilization of various nucleophiles as coupling partners together with reaction optimization (including the choice of copper source, ligands, base, and other additives), limitations, scope, and mechanisms are examined; these have benefitted the development of efficient and milder methods. The synthesis of medicinally valuable or pharmaceutically important nitrogen heterocycles, including isotope-labeled compounds, is also included. Chan–Lam coupling reaction can now form twelve different C–element bonds, making it one of the most diverse and mild reactions known in organic chemistry.

1 Introduction

2 Construction of C–N and C–O Bonds

2.1 C–N Bond Formation

2.1.1 Original Discovery via Stoichiometric Copper-Mediated C–N Bond Formation

2.1.2 Copper-Catalyzed C–N Bond Formation

2.1.3 Coupling with Azides, Sulfoximines, and Sulfonediimines as Nitrogen­ Nucleophiles

2.1.4 Coupling with N,N-Dialkylhydroxylamines

2.1.5 Enolate Coupling with sp3-Carbon Nucleophiles

2.1.6 Nickel-Catalyzed Chan–Lam Coupling

2.1.7 Coupling with Amino Acids

2.1.8 Coupling with Alkylboron Reagents

2.1.9 Coupling with Electron-Deficient Heteroarylamines

2.1.10 Selective C–N Bond Formation for the Synthesis of Heterocycle-Containing Compounds

2.1.11 Using Sulfonato-imino Copper(II) Complexes

2.2 C–O Bond Formation

2.2.1 Coupling with (Hetero)arylboron Reagents

2.2.2 Coupling with Alkyl- and Alkenylboron Reagents

3 C–Element (Element = S, P, C, F, Cl, Br, I, Se, Te, At) Bond Forma tion under Modified Chan–Lam Conditions

4 Conclusions

Synthetic applications and methodology development of Chan-Lam coupling: a review

Chan-Lam coupling is one of the most popular and easy methods to perform arylation of amines (N-arylations). This cross-coupling is generally performed by reacting aryl boronate derivatives with a variety of substrates involving nitrogen containing functional groups such as amines, amides, ureas, hydrazine, carbamates. This article summarizes the synthetic applications of this reaction and the efforts of scientists to develop novel and efficient methodologies for this reaction.

Renovation of Optically Active Phenanthrolines as Powerful Chiral Ligands for Versatile Asymmetric Metal Catalysis

In the field of asymmetric synthesis, the development of new chiral ligands has been regarded as an attractive challenge for decades. Novel chiral ligands can often have a great impact on synthetic protocols. In this context, we are currently interested in the application of 1,10-phenanthroline (phen) as an entirely new class of chiral ligand. To handle this issue, we designed a chiral phen ligand that provides the N,N,O-tridentate coordination of the phen moiety and an additional phenolic hydroxyl group. As phen possesses greater coordination ability with various ions, our chiral phen ligand would be valuable as one of the "privileged" chiral ligands applied to a broad range of metal catalysts and new reactions. This account summarizes the results of the application of the chiral phen ligand to various kinds of metal catalysis.