نتایج جستجو برای: desymmetrization

تعداد نتایج: 310  

Journal: :Science 2017
Qing-Feng Wu Peng-Xiang Shen Jian He Xiao-Bing Wang Forrest Zhang Qian Shao Ru-Yi Zhu Claudio Mapelli Jennifer X Qiao Michael A Poss Jin-Quan Yu

The enzymatic β-C-H hydroxylation of the feedstock chemical isobutyric acid has enabled the asymmetric synthesis of a wide variety of polyketides. The analogous transition metal-catalyzed enantioselective β-C-H functionalization of isobutyric acid-derived substrates should provide a versatile method for constructing useful building blocks with enantioenriched α-chiral centers from this abundant...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2007
Byunghyuck Jung Sung Ho Kang

Catalytic enantioselective desymmetrization of meso-2-substituted glycerols has been developed to secure a novel synthetic route to chiral tertiary alcohols. The transformation has been realized by monobenzoylation using benzoyl chloride and triethylamine in the presence of the imine ligand (25)-CuCl2 complex in THF at ambient temperature. The desymmetrization turned out to be greatly dependent...

Journal: :International Journal of Applied Chemistry 2020

Journal: :Chemical Society Reviews 2021

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

Journal: :Chemical communications 2015
Jianlin Zhang Yulong Zhang Lili Lin Qian Yao Xiaohua Liu Xiaoming Feng

The catalytic asymmetric Michael addition/desymmetrization reaction of N-(2-t-butylphenyl)maleimides with unprotected 3-substituted-2-oxindoles was successfully realized using a chiral N,N'-dioxide-Sc(III) complex, leading to succinimides with two kinds of stereogenic elements—atom chirality and axial chirality—in up to 99% yield, 99% ee and >19 : 1 d.r.

Journal: :Chemical communications 2012
Nelma Carurucan Celindro Tae Woo Kim Sung Ho Kang

The enantioselective synthesis of (-)-dysiherbaine (1) has been established with efficiency via a unique synthetic strategy involving the desymmetrization of 2-substituted glycerol to install a quaternary chiral carbon, which induces further stereochemistry in the bicyclic perhydrofuropyran through mercuriocyclization and epoxidation.

Journal: :Angewandte Chemie 2011
Xixi Sun Amanda D Worthy Kian L Tan

Ex-changing places: a highly enantioselective desymmetrization of 1,2-diols has been developed in which the catalyst utilizes reversible covalent bonding to the substrate to achieve both high selectivity and rate acceleration (see scheme, PMP=pentalmethylpiperidine, TBS=tert-butyldimethylsilyl). Induced intramolecularity is responsible for the enhanced rate, thus allowing the reaction to be per...

2014
Anna M Rydzik Ivanhoe K H Leung Grazyna T Kochan Michael A McDonough Timothy D W Claridge Christopher J Schofield

γ-Butyrobetaine hydroxylase (BBOX) is a 2-oxoglutarate dependent oxygenase that catalyzes the final hydroxylation step in the biosynthesis of carnitine. BBOX was shown to catalyze the oxidative desymmetrization of achiral N,N-dialkyl piperidine-4-carboxylates to give products with two or three stereogenic centers.

Journal: :Journal of the American Chemical Society 2016
Zhijian Huang Xuan Huang Baosheng Li Chengli Mou Song Yang Bao-An Song Yonggui Robin Chi

A carbene-catalyzed desymmetrization of prochiral bisphenol compounds bearing remote P-stereogenic centers is disclosed. The catalytic reactions can be performed on gram scales with 1 mol % N-heterocyclic carbene (NHC) catalyst, providing efficient access to enantiomerically enriched P-stereogenic phosphinates. The chiral phosphinates prepared with our method can find widespread applications as...

Journal: :Organic & biomolecular chemistry 2010
Karla Bravo-Altamirano Laëtitia Coudray Eric L Deal Jean-Luc Montchamp

Access to P-chiral H-phosphinates via desymmetrization of hypophosphite esters was investigated. The use of chiral auxiliaries, chiral catalysts, and of a bulky prochiral group that could lead to kinetic resolution was explored. A chiral NMR assay for enantiomeric excess determination of H-phosphinates was developed. An asymmetric route to C-chiral H-phosphinates is also examined and an assay w...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید