Attrition‐Enhanced Asymmetric Transformation of Axially Chiral Nicotinamides by Dynamic Chiral Salt Formation

ChemPlusChem ◽  
2021 ◽  
Author(s):  
Takumi Nakamura ◽  
Hiroki Ishikawa ◽  
Kazuma Ban ◽  
Yasushi Yoshida ◽  
Takashi Mino ◽  
...  
Keyword(s):  
Salt Formation ◽  
Axially Chiral ◽  
Asymmetric Transformation

scholarly journals Atroposelective transformation of axially chiral (hetero)biaryls. From desymmetrization to modern resolution strategies

2021 ◽  
Author(s):  
José A. Carmona ◽  
Carlos Rodríguez-Franco ◽  
Rosario Fernández ◽  
Valentín Hornillos ◽  
José M. Lassaletta
Keyword(s):  
Kinetic Resolution ◽  
Starting Material ◽  
Dynamic Kinetic Resolution ◽  
Axially Chiral ◽  
Asymmetric Transformation ◽  
And Behavior ◽  
Resolution Strategies

Atroposelective transformations of (hetero)biaryls are classified into desymmetrization, kinetic resolution, dynamic kinetic resolution, and dynamic kinetic asymmetric transformation depending on the nature and behavior of the starting material.

scholarly journals Deracemization of Axially Chiral Nicotinamides by Dynamic Salt Formation with Enantiopure Dibenzoyltartaric Acid (DBTA)

Molecules ◽  
2013 ◽  
Vol 18 (11) ◽  
pp. 14430-14447 ◽  
Author(s):  
Fumitoshi Yagishita ◽  
Norifumi Kamataki ◽  
Kazuma Okamoto ◽  
Shota Kanno ◽  
Takashi Mino ◽  
...  
Keyword(s):  
Salt Formation ◽  
Axially Chiral

ChemInform Abstract: Asymmetric Transformation of (RS)-1,2,3,4-Tetrahydro-3- isoquinolinecarboxylic Acid via Salt Formation with (1S)-10- Camphorsulfonic Acid.

ChemInform ◽  
2010 ◽  
Vol 23 (14) ◽  
pp. no-no
Author(s):  
T. SHIRAIWA ◽  
T. FURUKAWA ◽  
T. TSUCHIDA ◽  
S. SAKATA ◽  
M. SUNAMI ◽  
...  
Keyword(s):  
Salt Formation ◽  
Camphorsulfonic Acid ◽  
Asymmetric Transformation

Racemization of Optically Active AromaticN-Acetylamino Acids and Asymmetric Transformation ofN-Acetyl-2-(4-hydroxyphenyl)glycine via Salt Formation with Optically Active α-Methylbenzylamine

1992 ◽  
Vol 65 (4) ◽  
pp. 965-970 ◽  
Author(s):  
Tadashi Shiraiwa ◽  
Shinji Sakata ◽  
Hisashi Natsuyama ◽  
Keiko Fujishima ◽  
Hideya Miyazaki ◽  
...  
Keyword(s):  
Optically Active ◽  
Salt Formation ◽  
Asymmetric Transformation

scholarly journals Asymmetric Transformation of (RS)-1,2,3,4-Tetrahydro-3-isoquinolinecarboxylic Acid via Salt Formation with (1S)-10-Camphorsulfonic Acid

1991 ◽  
Vol 64 (12) ◽  
pp. 3729-3731 ◽  
Author(s):  
Tadashi Shiraiwa ◽  
Tsuyoshi Furukawa ◽  
Tamotsu Tsuchida ◽  
Shinji Sakata ◽  
Michio Sunami ◽  
...  
Keyword(s):  
Salt Formation ◽  
Camphorsulfonic Acid ◽  
Asymmetric Transformation

Total Synthesis of Axially-Chiral Cannabinols: A New Platform for Cannabinoid-Based Drug Discovery

2019 ◽  
Author(s):  
Primali Navaratne ◽  
Jenny Wilkerson ◽  
Kavindri Ranasinghe ◽  
Evgeniya Semenova ◽  
Lance McMahon ◽  
...  
Keyword(s):  
Drug Discovery ◽  
Total Synthesis ◽  
Ground State ◽  
Chemical Space ◽  
Modern Medicine ◽  
The Novel ◽  
Pharmaceutical Development ◽  
Bioactive Component ◽  
Axially Chiral ◽  
New Directions

<div> <div> <div> <p>Phytocannabinoids, molecules isolated from cannabis, are gaining attention as promising leads in modern medicine, including pain management. Considering the urgent need for combating the opioid crisis, new directions for the design of cannabinoid-inspired analgesics are of immediate interest. In this regard, we have hypothesized that axially-chiral-cannabinols (ax-CBNs), unnatural (and unknown) isomers of cannabinol (CBN) may be valuable scaffolds for cannabinoid-inspired drug discovery. There are multiple reasons for thinking this: (a) ax-CBNs would have ground-state three-dimensionality akin to THC, a key bioactive component of cannabis, (b) ax-CBNs at their core structure are biaryl molecules, generally attractive platforms for pharmaceutical development due to their ease of functionalization and stability, and (c) atropisomerism with respect to phytocannabinoids is unexplored “chemical space.” Herein we report a scalable total synthesis of ax-CBNs, examine physical properties experimentally and computationally, and provide preliminary behavioral and analgesic analysis of the novel scaffolds. </p> </div> </div> </div>

Synthesis of Axially Chiral 2,2’-Bisphosphobiarenes via a Nickel-Catalyzed Asymmetric Ullmann Coupling: General Access to Privileged Chiral Ligands without Optical Resolution

2020 ◽  
Author(s):  
Ziqing Zuo ◽  
Raphael Kim ◽  
Donald Watson
Keyword(s):  
Optical Resolution ◽  
Chiral Ligands ◽  
Chiral Auxiliaries ◽  
Axially Chiral ◽  
Ullmann Coupling

<div><p>We report an asymmetric Ullmann-type homocoupling of <i>ortho-</i>(iodo)arylphosphine oxides and <i>ortho</i>-(iodo)arylphosphonates that results in highly enantioenriched axially chiral bisphosphine oxides and bisphosphonates in good yields and excellent enantioselectivities. These products are readily converted to enantioenriched biaryl bisphosphines without need for chiral auxiliaries or optical resolution. This process provides a straightforward and practical route for the development of previously uninvestigated atroposelective biaryl bisphosphine ligands.</p></div>

Axially Chiral Bis(α-amino Acid)s and Their Deamino Analogues. Synthesis and Configurational Assignment

1998 ◽  
Vol 63 (2) ◽  
pp. 211-221 ◽  
Author(s):  
Miloš Tichý ◽  
Luděk Ridvan ◽  
Miloš Buděšínský ◽  
Jiří Závada ◽  
Jaroslav Podlaha ◽  
...  
Keyword(s):  
Amino Acid ◽  
Nmr Spectra ◽  
Building Blocks ◽  
X Ray Diffraction ◽  
Amino Groups ◽  
X Ray ◽  
Configurational Assignment ◽  
Symmetry Properties ◽  
Axially Chiral ◽  
Polymeric Structures

The axially chiral bis(α-amino acid)s cis-2 and trans-2 as possible building blocks for polymeric structures of novel type of helicity were prepared. Their configuration has been determined by NMR spectroscopy and, in the case of the trans-isomer, confirmed by single-crystal X-ray diffraction. Analogous pair of stereoisomeric diacids cis-3 and trans-3, devoid of the amino groups, was also prepared and their configuration assigned. The observed differences in the NMR spectra of cis- and trans-isomers of 2 and 3 are discussed from the viewpoint of their different symmetry properties.

Remote Stereocontrolled Construction of Vicinal Axially Chiral Tetrasubstituted Allenes and Heteroatom-Functionalized Quaternary Carbon Stereocenters

2019 ◽  
Vol 21 (2) ◽  
pp. 503-507 ◽  
Author(s):  
Pei Zhang ◽  
Qiuhong Huang ◽  
Yuyu Cheng ◽  
Rongshi Li ◽  
Pengfei Li ◽  
...  
Keyword(s):  
Quaternary Carbon ◽  
Axially Chiral

scholarly journals New Bifunctional Bis(azairidacycle) with Axial Chirality via Double Cyclometalation of 2,2′-Bis(aminomethyl)-1,1′-binaphthyl

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1165
Author(s):  
Yasuhiro Sato ◽  
Yuichi Kawata ◽  
Shungo Yasui ◽  
Yoshihito Kayaki ◽  
Takao Ikariya
Keyword(s):  
Hydrogen Transfer ◽  
Bond Cleavage ◽  
Enantiomeric Excess ◽  
Transfer Hydrogenation ◽  
Catalyst Precursor ◽  
Asymmetric Catalysts ◽  
Axially Chiral ◽  
Diastereomeric Mixture ◽  
Raney Ni ◽  
Half Sandwich

As a candidate for bifunctional asymmetric catalysts containing a half-sandwich C–N chelating Ir(III) framework (azairidacycle), a dinuclear Ir complex with an axially chiral linkage is newly designed. An expedient synthesis of chiral 2,2′-bis(aminomethyl)-1,1′-binaphthyl (1) from 1,1-bi-2-naphthol (BINOL) was accomplished by a three-step process involving nickel-catalyzed cyanation and subsequent reduction with Raney-Ni and KBH4. The reaction of (S)-1 with an equimolar amount of [IrCl2Cp*]2 (Cp* = η5–C5(CH3)5) in the presence of sodium acetate in acetonitrile at 80 °C gave a diastereomeric mixture of new dinuclear dichloridodiiridium complexes (5) through the double C–H bond cleavage, as confirmed by 1H NMR spectroscopy. A loss of the central chirality on the Ir centers of 5 was demonstrated by treatment with KOC(CH3)3 to generate the corresponding 16e amidoiridium complex 6. The following hydrogen transfer from 2-propanol to 6 provided diastereomers of hydrido(amine)iridium retaining the bis(azairidacycle) architecture. The dinuclear chlorido(amine)iridium 5 can serve as a catalyst precursor for the asymmetric transfer hydrogenation of acetophenone with a substrate to a catalyst ratio of 200 in the presence of KOC(CH3)3 in 2-propanol, leading to (S)-1-phenylethanol with up to an enantiomeric excess (ee) of 67%.

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