37031-30-4Relevant articles and documents
Chiral Aluminum Complex Controls Enantioselective Nickel-Catalyzed Synthesis of Indenes: C?CN Bond Activation
Luan, Yu-Xin,Peng, Qian,Ye, Mengchun,Zhang, Tao,Zheng, Su-Juan
supporting information, p. 7439 - 7443 (2020/03/24)
A chiral aluminum complex controlled, enantioselective nickel-catalyzed domino reaction of aryl nitriles and alkynes proceeding by C?CN bond activation was developed. The reaction provides various indenes, bearing chiral all-carbon quaternary centers, under mild reaction conditions in yields of 32 to 91 percent and ee values within the 73–98 percent range. The reaction mechanism and aspects of stereocontrol were investigated by DFT calculations.
Synthesis of (+)-goniopypyrone and (+)-goniotriol using Pd-catalyzed carbonylation
Miyazawa, Yuki,Sugimoto, Makoto,Tanaka-Oda, Ayumi,Makabe, Hidefumi
, (2019/08/16)
Syntheses of (+)-goniopypyrone and (+)-goniotriol isolated from Goniothalamus giganteus were achieved. The key steps involve Pd-catalyzed carbonylation for lactone ring formation and diastereoselective reduction of ynone using the (R)-CBS catalyst and borane dimethyl sulfide complex.
Stereocontrolled synthesis of four isomeric linoleate triols of relevance to skin barrier formation and function
Davis, Robert W.,Allweil, Alexander,Tian, Jianhua,Brash, Alan R.,Sulikowski, Gary A.
supporting information, p. 4571 - 4573 (2018/11/23)
Linoleate triol esters are intermediates along the pathway of formation of the mammalian skin permeability barrier. In connection with the study of their involvement in barrier formation we required access to isomerically pure and defined samples of four linoleate triol esters. A common synthetic strategy was developed starting from isomeric alkynols derived from D-tartaric acid and 2-deoxy-D-ribose.
Enantioselective Direct Synthesis of syn- and anti-α,β-Dihydroxy γ-Keto Esters Using a Dinuclear Zinc–AzePhenol Complex
Zhang, Zhao-Fei,Yang, Xiao-Chao,Lu, Hui-Jie,Wang, Min-Can
, p. 785 - 793 (2018/02/21)
A one-step enantioselective direct synthesis of both syn- and anti-α,β-dihydroxy γ-keto esters using a dinuclear zinc–AzePhenol complex is presented. This asymmetric α-hydroxyacetate aldol reaction proceeds in moderate to good yield and with excellent ena
Chiroptical properties of 2,2’-bioxirane
Daugey,De Rycke,Brotin,Buffeteau
supporting information, p. 342 - 350 (2018/01/15)
The two enantiomers of 2,2′-bioxirane were synthesized, and their chiroptical properties were thoroughly investigated in various solvents by polarimetry, vibrational circular dichroism (VCD), and Raman optical activity (ROA). Density functional theory (DFT) calculations at the B3LYP/aug-cc-pVTZ level revealed the presence of three conformers (G+, G?, and cis) with Gibbs populations of 51, 44, and 5% for the isolated molecule, respectively. The population ratios of the two main conformers were modified for solvents exhibiting higher dielectric constants (G? form decreases whereas G+ form increases). The behavior of the specific optical rotation values with the different solvents was correctly reproduced by time-dependent DFT calculations using the polarizable continuum model (PCM), except for the benzene for which explicit solvent model should be necessary. Finally, VCD and ROA spectra were perfectly reproduced by the DFT/PCM calculations for the Boltzmann-averaged G+ and G? conformers.
Ni-Al Bimetallic Catalyzed Enantioselective Cycloaddition of Cyclopropyl Carboxamide with Alkyne
Liu, Qi-Sheng,Wang, De-Yin,Yang, Zhi-Jun,Luan, Yu-Xin,Yang, Jin-Fei,Li, Jiang-Fei,Pu, You-Ge,Ye, Mengchun
supporting information, p. 18150 - 18153 (2017/12/27)
A Ni-Al bimetallic catalyzed enantioselective cycloaddition reaction of cyclopropyl carboxamides with alkynes has been developed. A series of cyclopentenyl carboxamides were obtained in up to 99% yield and 94% ee. The bifunctional-ligand-enabled bimetallic catalysis proved to be an efficient strategy for the C-C bond cleavage of unreactive cyclopropanes.
Convergent Synthesis of the Dihydropyran Core Containing the C1-C15 Subunit of Sorangicin A Employing Gold(I)-Catalyzed Cyclization of an Allenic Alcohol
Raghavan, Sadagopan,Nyalata, Satyanarayana
supporting information, p. 10698 - 10706 (2016/11/29)
A convergent route to the C1-C15 subunit of sorangicin A is disclosed. The key steps include carbon-carbon bond formation using an α-chloro sulfide, regioselective hydrozirconation of an internal alkyne for the preparation of a trisubstituted iodoalkene, allene formation using the Myers-Movassaghi protocol, stereoselective reduction of allylic and propargylic ketones using Noyori's catalyst, and gold(I)-catalyzed cyclization of a β-hydroxy allene to construct the dihydropyran ring.
Design of Highly Stable Iminophosphoranes as Recyclable Organocatalysts: Application to Asymmetric Chlorinations of Oxindoles
Gao, Xing,Han, Jianwei,Wang, Limin
supporting information, p. 4596 - 4599 (2015/09/28)
A new family of tartaric acid derived chiral iminophosphoranes has been developed as highly effective organocatalysts in the asymmetric chlorinations of 3-substituted oxindoles with a high level of enantioselectivity. Importantly, these catalysts are air- and moisture-stable. Recovery of the catalyst after simple chromatographic separation for reuse in the model reaction was achieved; the catalyst can be recycled six times without loss of any enantioselectivity. Several advantages of this catalytic process are high conversion after a very short reaction time at ambient temperature, low catalytic loading, and scale-up to multigram quantities with an excellent enantiomeric excess value of >99%, which meets the enantiomeric purity required for pharmaceutical purposes.
Easily accessible TADDOL-derived bisphosphonite ligands: Synthesis and application in the asymmetric hydroformylation of vinylarenes
Allmendinger, Simon,Kinuta, Hirotaka,Breit, Bernhard
supporting information, p. 41 - 45 (2015/03/03)
The synthesis of chiral bidentate bisphosphonite ligands based on the TADDOL motif from readily available starting materials has been developed. Taking advantage of the modular nature of the building blocks, a diverse ligand library has been prepared. Their catalytic potential has been evaluated in the asymmetric hydroformylation of styrene and derivatives. These catalysts showed high activity and provided the aldehydes in high enantiomeric purity.
Versicolactones A and B: Total synthesis and structure revision
Wang, Liping,Zhu, Weiming
supporting information, p. 6729 - 6731 (2013/11/19)
To further determine absolute configurations of versicolactones A and B, total synthesis of versicolactones A and B and their six stereoisomers were reported in this Letter. The 1H and 13C NMR spectra of the synthetic erythro-stereoisomers matched perfectly with those of the natural products. Combined with the comparison of the specific rotations, the absolute configuration of versicolactones A and B were revised as (4Z,6R,7S)- and (4E,6R,7S)- from the corresponding (4Z,6R,7R)- and (4E,6R,7R)-6,7-dihydroxyocta- 2,4-dien-4-lactone, respectively.