145624-56-2Relevant academic research and scientific papers
Enantiopure (P)- and (M)-3,14-bis(o-hydroxyaryl)tetrahydrobenzo[5]helicenediols and their helicene analogues: Synthesis, amplified circularly polarized luminescence and catalytic activity in asymmetric hetero-Diels–Alder reactions
Fang, Lei,Li, Meng,Lin, Wei-Bin,Chen, Chuan-Feng
, p. 7164 - 7172 (2018)
Three pairs of enantiopure (P)- and (M)-3,14-bis(o-hydroxyaryl)tetrahydrobenzo[5]helicenediols (ArOH-H[5]HOLs), and enantiomers (P)- and (M)-3,14-bis(o-hydroxyphenyl)benzo[5]helicene-diols (PhOH-[5]HOLs) were designed and synthesized. It was found that co
Axially chiral biaryl diols catalyze highly enantioselective hetero-diels-alder reactions through hydrogen bonding
Unni, Aditya K.,Takenaka, Norito,Yamamoto, Hisashi,Rawal, Viresh H.
, p. 1336 - 1337 (2005)
Axially chiral 1,1′-biaryl-2,2′-dimethanol (3, BAMOL) family of diols are highly effective catalysts for enantioselective hetero-Diels-Alder reactions between aminosiloxydiene 1 and a wide variety of unactivated aldehydes. The reactions proceed in useful
Improvement of the reactivity and selectivity of the oxo-Diels-Alder reaction by steric modification of the salen-chromium catalyst
Cha?adaj, Wojciech,Kwiatkowski, Piotr,Jurczak, Janusz
, p. 6810 - 6811 (2008)
Salen-chromium(III) complexes bearing sterically demanding substituents at the 3 and 3′ positions are applied for the oxo-Diels-Alder reaction of various aldehydes with Danishefsky's diene. The readily-accessible complex bearing a bulky 3-phenylpent-3-yl substituent revealed its potential affording the cycloadducts with improved reactivity and excellent selectivities up to 96% ee, being considerably superior to the classic Jacobsen's catalyst.
Chiral Chromium Salen@rGO as Multipurpose and Recyclable Heterogeneous Catalyst
Abd El Sater, Mariam,Mellah, Mohamed,Dragoe, Diana,Kolodziej, Emilie,Jaber, Nada,Schulz, Emmanuelle
supporting information, p. 9454 - 9460 (2021/05/26)
The first immobilization of a pyrene-tagged chromium salen complex through π-π noncovalent interactions on reduced graphene oxide (rGO) is described. A very robust supported catalytic system is obtained to promote asymmetric catalysis in repeated cycles, without loss of activity or enantioselectivity. This specific behavior was demonstrated in two different catalytic reactions (up to ten reuses) promoted by chromium salen complexes, the cyclohexene oxide ring-opening reaction and the hetero-Diels-Alder cycloaddition between various aldehydes and Danishefsky's diene. Furthermore, the chiral chromium salen@rGO has been found to be compatible with a multi-substrate type use, in which the structure of the substrate involved is modified each time the catalyst is reused.
Catalytic asymmetric oxo-Diels-Alder reactions with chiral atropisomeric biphenyl diols
Yeung, Chi-Tung,Chan, Wesley Ting Kwok,Lo, Wai-Sum,Law, Ga-Lai,Wong, Wing-Tak
supporting information, p. 955 - 962 (2019/06/08)
New chiral atropisomeric biphenyl diols 3, 4 and 6 containing additional peripheral chiral centers with different steric bulkiness and/or electronic properties were synthesized. The X-ray crystal structure of 3 shows the formation of a supramolecular stru
C3-Symmetric Boron Lewis Acid with a Cage-Shape for Chiral Molecular Recognition and Asymmetric Catalysis
Konishi, Akihito,Nakaoka, Koichi,Maruyama, Hikaru,Nakajima, Hideto,Eguchi, Tomohiro,Baba, Akio,Yasuda, Makoto
supporting information, p. 1273 - 1277 (2017/02/05)
Chiral Lewis acids play an important role in the precise construction of various types of chiral molecules. Here, a cage-shaped borate 2 was designed and synthesized as a chiral Lewis acid that possesses a unique C3-symmetric structure composed of three homochiral binaphthyl moieties. The highly symmetrical structure of 2 with homochirality was clearly elucidated by X-ray crystallographic analysis. The peculiar chiral environment of 2?THF exhibited chiral recognition of some simple amines and a sulfoxide. Moreover, the application of 2?THF to hetero-Diels–Alder reactions as a chiral Lewis-acid catalyst afforded the enantioselective products, which were obtained through an entropy-controlled pathway according to the analysis of the relationship between optical yield and reaction temperature. In particular, the robust chiral reaction field of 2?THF allowed the first example of an asymmetric hetero-Diels–Alder reaction with a simple diene despite the requirement of high temperature.
Highly asymmetric hetero-Diels-Alder reaction using helical silica-supported Mn(III)-salen catalysts
Li, Le,Li, Yu,Pang, Di,Liu, Fei,Zheng, Aqun,Zhang, Guangbin,Sun, Yang
, p. 8096 - 8103 (2015/12/30)
Helical silica were prepared and functionalized by Mn(III)-salen complexes in order to catalyze asymmetric hetero-Diels-Alder reactions. Characterizations revealed doping of sodium lactate facilitated porosity, hydrolysis resistance and chiral configurati
Electropolymerization of chiral chromium-salen complexes: New materials for heterogeneous asymmetric catalysis
Zulauf, Anais,Hong, Xiang,Brisset, Francois,Schulz, Emmanuelle,Mellah, Mohamed
, p. 1399 - 1407 (2012/10/30)
Electrochemical oxidation is described as a very efficient polymerization procedure for the heterogenization of metallic chiral catalysts. From chromium chiral complexes based on salen-thiophene ligands, this methodology provided an efficient access to various polymers. Recovered as insoluble powders, these materials were tested in different enantioselective heterogeneous catalytic reactions. Structural modifications were introduced on the salen core in order to evaluate their influence on redox polymer properties and on the enantioselectivity of the catalysis. Electrochemical experiments showed the particular stability of these deposited materials at the electrode surface and SEM analyses suggested the influence of the electropolymerization conditions on their morphology.
cis-2,5-diaminobicyclo[2.2.2]octane, a new scaffold for asymmetric catalysis via salen-metal complexes
White, James D.,Shaw, Subrata
supporting information; experimental part, p. 2488 - 2491 (2011/06/25)
Chemical equations presented. A new C2 symmetric salen scaffold based on cis-2,5-diaminobicyclo[2.2.2]octane has been synthesized that forms complexes with a wide range of metals. The chromium(III) complex is shown to catalyze the hetero-Diels-
Enantioselective construction of cis-2,6-disubstituted dihydropyrans: Total synthesis of (-)-centrolobine
Chaladaj, Wojciech,Kowalczyk, Rafa,Jurczak, Janusz
supporting information; experimental part, p. 1740 - 1743 (2010/05/18)
(Chemical Equation Presentation) This paper presents a simple and efficient route to chiral cis-6-substituted 2-(2-hydroxyethyl)-5,6-dihydro-2H-pyrans, a versatile chiral building block. The strategy is based on three key transformations: enantioselective
