Palladium-catalyzed directed arylation of 2,2'-diacetamidobiaryls with aryl iodides provides efficient access to chiral ortho-substituted biaryl diamines. Aryl iodides with para- and meta-substituents are tolerated. Deprotection of the acetyl groups under basic conditions furnishes the free diamines, which should find broad utility in asymmetric catalysis.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2726659 | PMC |
http://dx.doi.org/10.1021/jo802632v | DOI Listing |
Small
November 2024
State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an, 710049, China.
The escalating demand for high-power and compact-size advanced electronic devices and power systems necessitates polymers to exhibit superior electrical properties even under harsh environments. However, reconciling the seemingly contradictory attributes of excellent electrical properties and thermal stability poses a formidable challenge for current epoxy polymer (EP) materials and their applications. To meet the need, here two classes of bi-aryl diamine curing agents are described that enable polymers to exhibit well-balanced thermal and dielectric properties with functional bridging groups.
View Article and Find Full Text PDFChemistry
December 2024
Key Laboratory of Chemistry in Ethnic Medicinal Resources, Key Laboratory of Natural Products Synthetic Biology of Ethnic Medicinal Endophytes, State Ethnic Affairs Commission & Ministry of Education, School of Ethnic Medicine, Yunnan Minzu University, Kunming, 650500, China.
The utilization of axially chiral biaryl diamines has been widely acknowledged as highly advantageous structures for the advancement of chiral catalysts and ligands. This highlights their extensive range of applications in asymmetric catalysis and synthesis. Herein, we devised a direct arylation reactions of 5-aminopyrazoles with azonaphthalenes, utilizing chiral phosphoric acid as the catalyst.
View Article and Find Full Text PDFJACS Au
February 2024
Department of Chemistry, Fudan University, 2005 Songhu Road, Shanghai 200438, China.
Atropisomeric biaryls have found crucial applications in versatile chiral catalysts as well as in ligands for transition metals. Herein, we have developed an efficient crystallization-induced deracemization (CID) method to access chiral biaryls from their racemates with a chiral ammonium salt under copper catalysis including BINOL, NOBIN, and BINAM derivatives. After being significantly accelerated by its bidentate diamine ligand, the copper catalyst exhibits high efficiency and selectivity in racemizing biaryl skeletons, and the cocrystal complex would be enantioselectively formed together with chiral ammonium salt, which on acid-quenching would directly deliver chiral biaryl without further chromatographic purification.
View Article and Find Full Text PDFMolecules
August 2022
Institute of Organic Chemistry of the Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
The series of -symmetric biaryl core-based non-racemic bisphosphines possessing substituents of different electronic properties: both EDG and EWG were obtained in a short sequence of good yielding transformations, started from commercial 1,3-dimethyl-2-nitrobenzene. Several different approaches leading to the desirable ligands were practically evaluated. Notably, the synthesis of the entire series of ligands could be performed with the utilization of a single early-stage precursor DIDAB (6,6'-diiodo-2,2',4,4'-tetramethylbiphenyl-3,3'-diamine), which could be easily obtained in enantiomerically pure form.
View Article and Find Full Text PDFChirality
May 2022
Department of Chemistry, Ludwig-Maximilians-University Munich, Munich, Germany.
Chiral compounds with a 1,2-diamine structure motif and their derivatives are of great interest in organic chemistry and are broadly used in asymmetric transformations, as chiral auxiliaries, (co)ligands, and ligand core structure. Here, we present a straightforward, diastereoselective synthesis for a diamide-bridged biaryl ligand. The ring closing reaction of the racemic atropos biphenyl 6,6'-dimethoxy-[1,1'-biphenyl]-2,2'-dicarboxylic acid with (R,R)-diaminocyclohexane yields the diasteromerically and enantiomerically pure cyclic (S ,R,R)-BIPOL, which can be used as a versatile chiral ligand.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!