180336-49-6Relevant articles and documents
Helicity of N,N′-diaryl-trans-1,2-diaminocyclohexane derivatives. Implications for molecular helicity manipulations
Kwit,Gawronski
, p. 9323 - 9331 (2003)
Derivatives of trans-1,2-diaminocyclohexane (DACH), useful as chiral ligands, scaffolds and building blocks, differ in their conformation. The conformation of N,N′-diaryl-DACH derivatives was studied by the semiempirical and DFT computational methods and by exciton-coupled circular dichroism. It was found that, contrary to M-helical N,N′-diimine, N,N′-diimide and N,N′-diamide derivatives, the aromatic residues in N,N′-diphenyl derivatives are oriented to form a P-helix for the (R,R)-DACH absolute configuration. The helicity of the bis-aryl system is modified in the case of 1-naphthyl or 2-naphthyl derivatives. Further switching of helicity has been demonstrated by either protonation or mono-N-acetylation of N,N′-diaryl DACH derivatives.
OXIDATIVE HOMO-COUPLING REACTIONS OF ARYL BORONIC ACIDS USING A POROUS COPPER METAL-ORGANIC FRAMEWORK AS A HIGHLY EFFICIENT HETEROGENEOUS CATALYST
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Page/Page column 23-28, (2011/02/24)
The disclosure provides methods for the use of open metal frameworks to synthesize biaryls comprising contacting a metal organic framework (MOF) or metal organic polyhedral (MOP) with an aryl boronic acid compound under conditions wherein the MOF or MOP catalyze the synthesis of the biaryl through a homo-coupling reaction.
Highly reactive, general and long-lived catalysts for palladium-catalyzed amination of heteroaryl and aryl chlorides, bromides, and iodides: Scope and structure-activity relationships
Shen, Qilong,Ogata, Tokutaro,Hartwig, John F.
, p. 6586 - 6596 (2008/12/22)
We describe a systematic study of the scope and relationship between ligand structure and activity for a highly efficient and selective class of catalysts containing sterically hindered chelating alkylphosphines for the amination of heteroaryl and aryl chlorides, bromides, and iodides. In the presence of this catalyst, aryl and heteroaryl chlorides, bromides, and iodides react with many primary amines in high yields with part-per-million quantities of palladium precursor and ligand. Many reactions of primary amines with both heteroaryl and aryl chlorides, bromides, and iodides occur to completion with 0.0005-0.05 mol % catalyst. A comparison of the reactivity of this catalyst for the coupling of primary amines at these loadings is made with catalysts generated from hindered monophosphines and carbenes, and these data illustrate the benefits of chelation. Studies on structural variants of the most active catalyst indicate that a rigid backbone in the bidentate structure, strong electron donation, and severe hindrance all contribute to its high reactivity. Thus, these complexes constitute a fourth-generation catalyst for the amination of aryl halides, whose activity complements catalysts based on monophosphines and carbenes.