852818-69-0Relevant academic research and scientific papers
Synthesis method of chiral trans-2-substituted naphthenic alcohol
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Paragraph 0041-0045; 0086-0089, (2021/09/08)
The invention relates to a synthesis method of chiral trans-2-substituted naphthenic alcohol. The invention provides a method for synthesizing chiral trans-cycloalkanol through asymmetric hydrogenation of palladium-catalyzed 2-substituted cyclic ketone. According to the method,a chiral diphosphine P-P * complex of metal palladium is taken as a catalyst, an acid additive is used in cooperation, asymmetric hydrogenation is carried out on a 2-substituted cyclic ketone compound to obtain a corresponding chiral trans-cycloalkanol compound. the enantiomeric excess of the chiral trans-cycloalkanol compound can reach 97% at most, and the trans-selectivity of the chiral trans-cycloalkanol compound is up to 20: 1. The method is simple and convenient to operate, practical, easy to implement, high in yield, high in atom economy and environment-friendly; the catalyst is commercially available; the reaction conditions are mild; and the method has a potential practical application value.
Palladium-catalyzed asymmetric hydrogenation of 2-aryl cyclic ketones for the synthesis oftranscycloalkanols through dynamic kinetic resolution under acidic conditions
Li, Xiang,Zhao, Zi-Biao,Chen, Mu-Wang,Wu, Bo,Wang, Han,Yu, Chang-Bin,Zhou, Yong-Gui
supporting information, p. 5815 - 5818 (2020/06/03)
The first efficient palladium-catalyzed asymmetric hydrogenation of 2-aryl cyclic ketones has been described through dynamic kinetic resolution under acidic conditions, providing a facile access to chiraltranscycloalkanol derivatives with excellent enantioselectivities.
Enantioselective cross-coupling of meso -epoxides with aryl halides
Zhao, Yang,Weix, Daniel J.
supporting information, p. 3327 - 3340 (2015/03/30)
The first enantioselective cross-electrophile coupling of aryl bromides with meso-epoxides to form trans-β-arylcycloalkanols is presented. The reaction is catalyzed by a combination of (bpy)NiCl2 and a chiral titanocene under reducing conditions. Yields range from 57 to 99% with 78-95% enantiomeric excess. The 30 examples include a variety of functional groups (ether, ester, ketone, nitrile, ketal, trifluoromethyl, sulfonamide, sulfonate ester), both aryl and vinyl halides, and five- to seven-membered rings. The intermediacy of a carbon radical is strongly suggested by the conversion of cyclooctene monoxide to an aryl [3.3.0]bicyclooctanol.
Highly enantioselective organocatalytic oxidative kinetic resolution of secondary alcohols using chiral alkoxyamines as precatalysts: Catalyst structure, active species, and substrate scope
Murakami, Keiichi,Sasano, Yusuke,Tomizawa, Masaki,Shibuya, Masatoshi,Kwon, Eunsang,Iwabuchi, Yoshiharu
supporting information, p. 17591 - 17600 (2015/02/19)
The development and characterization of enantioselective organocatalytic oxidative kinetic resolution (OKR) of racemic secondary alcohols using chiral alkoxyamines as precatalysts are described. A number of chiral alkoxyamines have been synthesized, and their structure-enantioselectivity correlation study in OKR has led us to identify a promising precatalyst, namely, 7-benzyl-3-n-butyl-4-oxa-5-azahomoadamantane, which affords various chiral aliphatic secondary alcohols (ee up to >99%, krel up to 296). In a mechanistic study, chlorine-containing oxoammonium species were identified as the active species generated in situ from the alkoxyamine precatalyst, and it was revealed that the chlorine atom is crucial for high reactivity and enantioselectivity. The present OKR is the first successful example applicable to various unactivated aliphatic secondary alcohols, including heterocyclic alcohols with high enantioselectivity, the synthetic application of which is demonstrated by the synthesis of a bioactive compound.
Highly enantioselective organocatalytic oxidative kinetic resolution of secondary alcohols using chirally Modified AZADOs
Tomizawa, Masaki,Shibuya, Masatoshi,Iwabuchi, Yoshiharu
supporting information; experimental part, p. 1828 - 1831 (2009/09/06)
A highly enantioselective organocatalytic oxidative kinetic resolution (OKR) of racemic secondary alcohols has been accomplished using asymmetric organocatalysis. A panel of chirally modified 2-azaadamantane N-oxyls (AZADOs) exhibit superior catalytic act
