Chiral Porous Carbon Surfaces for Enantiospecific Synthesis by Sapir Shekef Aloni, Molhm Nassir, Yitzhak Mastai

“…An aldol surface chiral catalytic reaction was devised and allowed to determine the root of the enantiomeric excess. These results affirm the path toward a new type of chiral surface.…”
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Homochiral Metal-Organic Framework Based Mixed Matrix Membrane for Chiral Resolution by Hwa-Jin Choi, Dong-Yeun Koh

“…Enantioselective polymer membranes have been developed for the chiral resolution of pharmaceuticals; however, it is difficult to generate sufficient enantiomeric excess (ee) with polymer membranes. In this work, a homochiral filler of L-His-ZIF-8 was synthesized by the ligand substitution method and mixed with polyamide(imide) (i.e., Torlon^®) to fabricate an enantioselective mixed-matrix membrane (MMM). …”
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Development of a novel technology to immobilise enzymes in the mesoporous Zr02 matrix and applications in the large scale asymmetric resolution of chiral compounds by Ching, Chi Bun.

“…When immobilized on erucic acid modified zirconia, both lipases gave significantly higher activity and enantiomeric excess compared with those from their corresponding crude lipase powders. …”
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A general method for asymmetric arylation and vinylation of silyl ketene acetals by Yang, Junfeng, Zhou, Jianrong (Steve)

“…The new stereocenters α to the ester groups were formed in high enantiomeric excess. The method was applied to the asymmetric synthesis of Profen drugs on a gram scale.…”
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Highly enantioselective rhodium-catalyzed cross-coupling of boronic acids and racemic allyl halides by González, J, Van Dijk, L, Goetzke, F, Fletcher, S

“…These reactions are catalyzed by a rhodium-ligand complex and typically display very high levels of enantioselectivity (>95% enantiomeric excess (ee)). In this protocol, we detail a procedure using a dihydropyridine-derived allyl chloride for the synthesis of (-)-(S)-tert-butyl-3-(4-bromophenyl)-3,6-dihydropyridine-1(2H)-carboxylate, an intermediate in the synthesis of the anticancer drug niraparib. …”

Chemical Composition, Enantiomeric Distribution, and Sensory Evaluation of the Essential Oils Distilled from the Ecuadorian Species <i>Myrcianthes myrsinoides</i> (Kunth) Grifo and... by Mayra Montalván, Manuel Alejandro Peñafiel, Jorge Ramírez, Nixon Cumbicus, Nicole Bec, Christian Larroque, Carlo Bicchi, Gianluca Gilardoni

“…Major compounds (&gt;5.0%) were limonene (5.3%&#8722;5.2%), 1,8-cineole (10.4%&#8722;11.6%), (<i>Z</i>)-caryophyllene (16.6%&#8722;16.8%), <i>trans</i>-calamenene (15.9%&#8722;14.6%), and spathulenol (6.2%&#8722;6.5%). The enantiomeric excess of eight chiral constituents was determined, being (+)-limonene and (+)-germacrene D enantiomerically pure. …”
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Role of Asymmetric Autocatalysis in the Elucidation of Origins of Homochirality of Organic Compounds by Kenso Soai, Tsuneomi Kawasaki, Arimasa Matsumoto

“…In the asymmetric autocatalysis with amplification of enantiomeric excess (ee), the very low ee (ca. 0.00005%) of 2-alkynyl-5-pyrimidyl alkanol was significantly amplified to &gt;99.5% ee with an increase in the amount. …”
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Enantioselective Mixed Matrix Membranes for Chiral Resolution by Hwa-Jin Choi, Yun-Ho Ahn, Dong-Yeun Koh

“…Enantioselective polymer membranes have been developed for chiral resolution of pharmaceuticals; however, it is difficult to generate sufficient enantiomeric excess (ee) with conventional polymers. This article describes a chiral resolution strategy using a composite structure of mixed matrix membrane that employs chiral fillers. …”
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Ultra-high-throughput mapping of the chemical space of asymmetric catalysis enables accelerated reaction discovery by Wenjing Nie, Qiongqiong Wan, Jian Sun, Moran Chen, Ming Gao, Suming Chen

“…The ultrafast ( ~ 1000 reactions/day) and accurate (median error < ±1%) analysis of enantiomeric excess are achieved through the ion mobility-mass spectrometry combines with the diastereoisomerization strategy. …”
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Enantioselective nickel catalysis : exploiting activated C-H bonds by Bencivenga, Nicholas Ernest

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Palladium-Catalyzed Enantioselective α-Arylation and α-Vinylation of Oxindoles Facilitated by an Axially Chiral P-Stereogenic Ligand by Taylor, Alexander M., Altman, Ryan A., Buchwald, Stephen Leffler

“…The resultant quaternary carbon stereocenters are formed in high enantiomeric excess, and the conditions tolerate a range of substitution on both the oxindole and the aryl/vinyl coupling partners.…”
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High performance continuous-wave laser cavity enhanced polarimetry using RF-induced linewidth broadening by Tran, D-B-A, Peverall, R, Rosson, S, Manfred, KM, Ritchie, GAD

“…Measurements of both a pure R-(+)-limonene sample and a non-racemic mixture of limonene of unknown enantiomeric excess are also presented, illustrating the utility of the technique.…”

Resolution of a Configurationally Stable Hetero[4]helicene by Michela Lupi, Martina Onori, Stefano Menichetti, Sergio Abbate, Giovanna Longhi, Caterina Viglianisi

“…Subsequent simple manipulations produced highly optically pure (≥ 99% enantiomeric excess) (<i>P</i>) and (<i>M</i>)-<b>1(OH)</b> in good yields. …”
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Preparation of 2'-13C-L-Histidine Starting from 13C-Thiocyanate: Synthetic Access to Any Site-Directed Stable Isotope Enriched L-Histidine by Sarra Talab, Kamal Khalifa Taha, Johan Lugtenburg

“…After deprotection L-histidine is obtained in good yield and 99% enantiomeric excess. 2'-13C-L-Histidine has been obtained via this new scheme with high (99%) 13C incorporation starting with commercially available 13C- thiocyanate. …”
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Efficient Asymmetric Simmons-Smith Cyclopropanation and Diethylzinc Addition to Aldehydes Promoted by Enantiomeric Aziridine-Phosphines by Aleksandra Buchcic-Szychowska, Justyna Adamczyk, Lena Marciniak, Adam Marek Pieczonka, Anna Zawisza, Stanisław Leśniak, Michał Rachwalski

“…Most of the desired products were formed in high chemical yields, with satisfactory values of enantiomeric excess (sometimes more than 90%) and diastereomeric ratios (in case of cyclopropanation reaction).…”
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A biocatalytic approach for resolution of 3-hydroxy-3-phenylpropanonitrile with the use of immobilized enzymes stabilized with ionic liquids by Oliwia Degórska, Daria Szada, Teofil Jesionowski, Jakub Zdarta

“…It was found that the most suitable IL was [BMIM]Cl; a process efficiency of 97.4 % and an enantiomeric excess (ee%) of 79.5 % were obtained when 1 % (w/v) of that IL in hexane was applied and the process was catalyzed by lipase immobilized on amine-modified silica.…”
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Whole Cells as Biocatalysts in Organic Transformations by Fabián Garzón-Posse, Liliana Becerra-Figueroa, José Hernández-Arias, Diego Gamba-Sánchez

“…Currently, the power and usefulness of biocatalysis in organic synthesis is undeniable, mainly due to the very high enantiomeric excess reached using enzymes, in an attempt to emulate natural processes. …”
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Screening of Biocatalysts for Synthesis of the Wieland–Miescher Ketone by Mitul P. Patel, Nathaneal T. Green, Jacob K. Burch, Kimberly A. Kew, Robert M. Hughes

“…As a direct outgrowth of this screen, we created an optimized procedure for Wieland–Miescher ketone (WMK) synthesis using crude lipase preparations, characterizing both reaction yield and enantiomeric excess. We also identified principal components of the crude lipase mixture through proteomics and present evidence for a non-lipolytic origin of the observed catalysis. …”
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NiH-catalyzed asymmetric hydroalkynylation of α,β-unsaturated amides by Yuanzheng Cheng, Zhuofan Gui, Ran Tao, You Wang, Shaolin Zhu

“…A wide range of α,β-unsaturated amides and bromoalkynes are suitable substrates for this reaction, which proceeds under mild conditions, allowing access to a variety of enantioenriched chiral β-alkynyl amides. β,γ-Unsaturated amides can also be used as substrates and undergo the β-selective hydroalkynylation with a slightly lower enantiomeric excess.…”
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Resolution of Halogenated Mandelic Acids through Enantiospecific Co-Crystallization with Levetiracetam by Jie Wang, Yangfeng Peng

“…Under the optimal conditions, the resolution efficiency reached up to 94% and the enantiomeric excess (%e.e.) of (<i>R</i>)-3-chloromandelic acid was 63%e.e. …”
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