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Journal articles on the topic 'Α stereoselectivity'

Author: Grafiati

Published: 4 June 2021

Last updated: 11 February 2022

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1

Ross, Günther, та Ivar Ugi. "Stereoselective syntheses of α-amino acid and peptide derivatives by the U-4CR of 5-desoxy-5-thio-D-xylopyranosylamine". Canadian Journal of Chemistry 79, № 12 (2001): 1934–39. http://dx.doi.org/10.1139/v01-186.

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Since 1961, the synthesis of α-amino acids derivatives by the four-component reaction of isocyanides (U-4CR) as a one-pot reaction has been developed. Only recently it was found that a variety of these α-amino acids compounds can be formed stereoselectively by the U-4CR using 1-amino-5-deoxy-5-thio-2,3,4-tri-O-isobutanoyl-β-D-xylopyranose as the amine component. The stereoselectivity inducing auxiliary 5-desoxy-5-thio-D-xylopyranosyl group of the so-formed products can be replaced selectively by hydrogen.Key words: stereoselective U-4CR, chiral amine component, amino carbohydrate, α-amino acid

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2

Štěpánek, Petr, Ondřej Vích, Lukáš Werner, Ladislav Kniežo, Hana Dvořáková та Pavel Vojtíšek. "Stereoselective Preparation of Precursors of α-C-(1→3)-Disaccharides". Collection of Czechoslovak Chemical Communications 70, № 9 (2005): 1411–28. http://dx.doi.org/10.1135/cccc20051411.

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The stereoselectivity of cycloaddition of sugar-containing substituted 1-(thiazol-2-yl)but-2-en-1-ones 1 and vinyl ethers was studied using the achiral vinyl ether/chiral catalyst as well as the chiral vinyl ether/achiral catalyst combinations. It has been shown that Eu(fod)3-catalyzed cycloaddition of oxadienes 1a-1e with the chiral vinyl ethers 9 and 10 affords stereoselectively almost pure cycloadducts 11a-11e and 12a-12e, respectively. The obtained cycloadducts are suitable precursors for the synthesis of α-C-(1→3)-disaccharides, containing 2-deoxy-arabino-hexopyranose moiety of D- or L-co

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3

Veeraraghavan Ramachandran, P., та Barnabas Otoo. "Facile synthesis of 1-trifluoromethylalkenes via the decarboxylation of α-trifluoromethyl-β-lactones". Chemical Communications 51, № 62 (2015): 12388–90. http://dx.doi.org/10.1039/c5cc03230j.

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DCC-mediated cyclodehydration of α-trifluoromethyl-β-hydroxy acids provides α-trifluoromethylated β-lactone intermediates, without loss of stereoselectivity. These lactones undergo facile decarboxylation providing a simple route to obtain both alkyl and aryl 1-trifluoromethyl alkenes in excellent yields and stereoselectivity.

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4

Alex, Catherine, Satsawat Visansirikul, and Alexei V. Demchenko. "A versatile approach to the synthesis of mannosamine glycosides." Organic & Biomolecular Chemistry 18, no. 34 (2020): 6682–95. http://dx.doi.org/10.1039/d0ob01640c.

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5

Lutz-Wahl, Sabine, Peter Fischer, Claudia Schmidt-Dannert, Wolfgang Wohlleben, Bernhard Hauer та Rolf D. Schmid. "Stereo- and Regioselective Hydroxylation of α-Ionone by Streptomyces Strains". Applied and Environmental Microbiology 64, № 10 (1998): 3878–81. http://dx.doi.org/10.1128/aem.64.10.3878-3881.1998.

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ABSTRACT A total of 215 Streptomyces strains were screened for their capacity to regio- and stereoselectively hydroxylate β- and/or α-ionone to the respective 3-hydroxy derivatives. With β-ionone as the substrate, 15 strains showed little conversion to 4-hydroxy- and none showed conversion to the 3-hydroxy product as desired. Among these 15 Streptomyces strains, S. fradiae Tü27, S. arenae Tü 495, S. griseus ATCC 13273, S. violaceoniger Tü 38, and S. antibioticus Tü 4 and Tü 46 converted α-ionone to 3-hydroxy-α-ionone with significantly higher hydroxylation activity compared to that of β-i

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6

Levitskiy, Oleg A., Olga I. Aglamazova, Yuri K. Grishin та ін. "Solvent-triggered stereoselectivity of α,α-cyclopropanation of amino acids in the Ni(ii) chiral coordination environment". Dalton Transactions 49, № 25 (2020): 8636–44. http://dx.doi.org/10.1039/d0dt01578d.

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Unexpected solvent-controlled increase in stereoselectivity of glycine cyclopropanation within chiral Ni(ii) coordination environment was observed and rationalized. Cyclopropanated diastereomeric complexes exhibit stereodependent redox-activity.

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7

Nakamura, Shuichi, Ryota Yamaji та Masaru Iwanaga. "Enantioselective construction of imidazolines having vicinal tetra-substituted stereocenters by direct Mannich reaction of α-substituted α-isocyanoacetates with ketimines". Chemical Communications 52, № 47 (2016): 7462–65. http://dx.doi.org/10.1039/c6cc02911f.

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8

Lamothe, S., K. L. Cook, and T. H. Chan. "Chiral organosilicon compounds in synthesis. Preparation and stereoselective alkylations of silylcinnamyl carbanions." Canadian Journal of Chemistry 70, no. 6 (1992): 1733–42. http://dx.doi.org/10.1139/v92-217.

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Silylallyl carbanions of type 13 bearing a chiral lithium complexing substituent remote from silicon can be alkylated regio- and stereoselectively at the α-position by small electrophiles in nonpolar solvents. The regiochemical outcome of the reaction was found to be highly dependent on the size of the incoming electrophile. Secondary alkyl halides react preferentially at the γ-center and good levels of stereoselectivity are still obtained in nonpolar solvents despite the rather long distance between the reacting center and the chiral auxiliary. Transformation of the alkylated allylsilanes int

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9

Bueno, M. P., C. Cativiela, C. Finol, J. A. Mayoral та C. Jaime. "Diels–Alder reactions of methyl-N-acyl-α,β-dehydroalaninates with cyclopentadiene". Canadian Journal of Chemistry 65, № 9 (1987): 2182–86. http://dx.doi.org/10.1139/v87-365.

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A study has been made of the Diels–Alder reaction of methyl-N-acetyl (and benzoyl)-α,β-dehydroalaninates with cyclopentadiene. In the reaction of methyl-N-acetyl-α,β-dehydroalaninate total conversion is obtained under several conditions, while the N-benzoyl derivative shows a lower reactivity. The stereoselectivity of the reaction is determined by 1H nuclear magnetic resonance spectroscopy. Perturbation MO calculations, using wave functions generated by the MNDO method, are used to rationalize the relative reactivity of the dienophiles and the stereoselectivity observed.

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10

Te Koppele, J. M., B. Coles, B. Ketterer та G. J. Mulder. "Stereoselectivity of rat liver glutathione transferase isoenzymes for α-bromoisovaleric acid and α-bromoisovalerylurea enantiomers". Biochemical Journal 252, № 1 (1988): 137–42. http://dx.doi.org/10.1042/bj2520137.

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The stereoselectivity of purified rat GSH transferases towards alpha-bromoisovaleric acid (BI) and its amide derivative alpha-bromoisovalerylurea (BIU) was investigated. GSH transferase 2-2 was the only enzyme to catalyse the conjugation of BI and was selective for the (S)-enantiomer. The conjugation of (R)- and (S)-BIU was catalysed by the isoenzymes 2-2, 3-3 and 4-4. Transferase 1-1 was less active, and no catalytic activity was observed with transferase 7-7. Isoenzymes 1-1 and 2-2 of the Alpha multigene family preferentially catalysed the conjugation of the (S)-enantiomer of BIU (and BI), w

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11

Sun, Wenxi, Cheng Peng, Zhigang Yao та Fan Xu. "Diastereoselective synthesis of α-dicarbonyl cyclopropanes via a lanthanide amide-catalysed reaction". Organic & Biomolecular Chemistry 17, № 27 (2019): 6620–28. http://dx.doi.org/10.1039/c9ob00732f.

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12

Li, Yan, та Zhiqiang Zhang. "Computational study on NHC catalyzed [4+2] annulation between γ-chloroenals and pyrazolinones: mechanism and stereoselectivity". New Journal of Chemistry 44, № 27 (2020): 11643–51. http://dx.doi.org/10.1039/d0nj01499k.

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13

Sun, Bing-Bing, Jun-Bo Chen, Jun-Qi Zhang, et al. "Organo-catalyzed asymmetric cascade annulation reaction for the construction of bi-spirocyclic pyrazolone and oxindole derivatives." Organic Chemistry Frontiers 7, no. 5 (2020): 796–809. http://dx.doi.org/10.1039/d0qo00001a.

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Organo-catalyzed tandem reaction between β,γ-unsaturated α-ketoesters and α-arylidene pyrazolinones was developed, and it provided chiral bi-spirocyclic pyrazolone and oxindole derivatives in high yields with good to excellent stereoselectivity.

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14

Cui, Yifan, Weilong Lin та Shengming Ma. "A metal-catalyzed new approach for α-alkynylation of cyclic amines". Chemical Science 10, № 6 (2019): 1796–801. http://dx.doi.org/10.1039/c8sc04115f.

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15

Jackson, WR, HA Jacobs, GS Jayatilake, BR Matthews та KG Watson. "Applications of Optically Active Aryl Cyanohydrins in the Synthesis of α-Hydroxy Aldehydes, α-Hydroxy Ketones and β-Hydroxy Amines". Australian Journal of Chemistry 43, № 12 (1990): 2045. http://dx.doi.org/10.1071/ch9902045.

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Cyanohydrins, prepared in high optical purity from aryl aldehydes, have been converted into α- hydroxy aldehydes, β- hydroxy ketones and β- hydroxy amines without any racemization and frequently with good stereoselectivity for the erythro-diastereoisomer (>90%) at the newly introduced stereogenic centre.

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16

Kong, Lingheng, Bingxian Liu, Xukai Zhou, Fen Wang та Xingwei Li. "Rhodium(iii)-catalyzed regio- and stereoselective benzylic α-fluoroalkenylation with gem-difluorostyrenes". Chemical Communications 53, № 74 (2017): 10326–29. http://dx.doi.org/10.1039/c7cc06048c.

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17

Mong, Kwok-Kong Tony, Tapan Kumar Pradhan, Cheng-Hsin Chiu, Wei-Cheng Hung, Chao-Ju Chen та Yi-Fang Wang. "(2-Ketulosonyl)onate 2,3-O-thionocarbonate donors for the synthesis of KO and KDO α-glycosides and a one-pot glycosylation method for 2-keto acid donors". Organic Chemistry Frontiers 7, № 16 (2020): 2179–86. http://dx.doi.org/10.1039/d0qo00630k.

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18

Majumdar, Moumita, Ravindra K. Raut, Padmini Sahoo, and Vikas Kumar. "Bis(chlorogermyliumylidene) and its significant role in elusive reductive cyclization." Chemical Communications 54, no. 77 (2018): 10839–42. http://dx.doi.org/10.1039/c8cc06067c.

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19

Mokar, Bhanudas Dattatray, Prakash D. Jadhav, Y. B. Pandit та Rai-Shung Liu. "Gold-catalyzed (4 + 2)-annulations between α-alkyl alkenylgold carbenes and benzisoxazoles with reactive alkyl groups". Chemical Science 9, № 19 (2018): 4488–92. http://dx.doi.org/10.1039/c8sc00986d.

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20

Harned, Andrew M. "α-Alkylation of a norbornene-derived tricyclic ketone: are steric factors really in control?" Chemical Communications 51, № 11 (2015): 2076–79. http://dx.doi.org/10.1039/c4cc07967a.

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21

Mackay, Simon P., and Patrick J. O' Malley. "Molecular Modelling of the Interactions between Optically Active Triazine Herbicides and Photosystem II." Zeitschrift für Naturforschung C 48, no. 5-6 (1993): 474–81. http://dx.doi.org/10.1515/znc-1993-5-612.

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Abstract The QB binding site of photosystem II in green plants displays stereoselectivity for the (S′) stereoisomer of the α-methylbenzyl derivative of atrazine but not for derivatives with smaller substituents such as sec-butyl. We have shown that interactive models reflect the experimental data by determining the intermolecular energies between the D1 protein binding region (residues Leu 210 to Val 280) and the triazine analogs. The intermolecular energy was calculated by van der Waals and electrostatic interactions after energy minimization of the combined structures to reduce inter and in

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22

Lu, Dong Ming, Zhi Jie Li, Feng Jiao Li та Qing Le Zeng. "Synthesis of α-Hydroxy Amides". Applied Mechanics and Materials 729 (січень 2015): 83–86. http://dx.doi.org/10.4028/www.scientific.net/amm.729.83.

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α-Hydroxy amides are a class of important intermediates in organic synthesis. It plays an important role in the field of science and medicine. However, the preparation methods of α-hydroxy amides are relatively few, and they are usually enzyme-or Lewis acid-catalyzed reactions. These types of methods are not ideal in operation, yield and/or stereoselectivity. We found a new way to synthesize α-hydroxy amides by transforming amino acids into α-hydroxyl acids, and then by amination of the α-hydroxy acids.

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23

Berthelot, Jacques, Yamina Benammar, and Bernard Desmazières. "Action of tetrabutylammonium tribromide with para-substituted chalcones in protic and aprotic media." Canadian Journal of Chemistry 73, no. 9 (1995): 1526–30. http://dx.doi.org/10.1139/v95-189.

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Bromination of the double bond of para-substituted chalcones under mild conditions in aprotic solvents is accomplished with high yields using tetrabutylammonium tribromide (TBABr3). In methanol, the main reaction is (α-β) bromomethoxylation. Stereoselectivity, regioselectivity, and chemioselectivity of this bromomethoxylation reaction are described. Keywords: bromination, bromomethoxylation, tetrabutylammonium tribromide, (α-β) dibromodihydrochalcones, α-bromo, β-methoxydihydrochalcones.

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24

Lin, Chaoqi, Jinbiao Jiao, Stéphane Maisonneuve, Julien Mallétroit, and Juan Xie. "Stereoselective synthesis and properties of glycoazobenzene macrocycles through intramolecular glycosylation." Chemical Communications 56, no. 22 (2020): 3261–64. http://dx.doi.org/10.1039/c9cc09853d.

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An intramolecular glycosylation approach has been successfully used to synthesize a series of photoswitchable glycomacrocycles with excellent α-stereoselectivity and interesting photochromic and chiroptical properties.

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25

Yasomanee, Jagodige P., Archana R. Parameswar, Papapida Pornsuriyasak, Nigam P. Rath, and Alexei V. Demchenko. "2,3-Di-O-picolinyl building blocks as glycosyl donors with switchable stereoselectivity." Organic & Biomolecular Chemistry 14, no. 11 (2016): 3159–69. http://dx.doi.org/10.1039/c6ob00107f.

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26

Ishii, Sayaka, Katsuya Saito, Shigefumi Kuwahara та Masaru Enomoto. "Unexpected reversal of stereochemistry observed in the addition of methallyltrimethylsilane to a chiral α-keto imide". Bioscience, Biotechnology, and Biochemistry 85, № 3 (2021): 488–92. http://dx.doi.org/10.1093/bbb/zbaa086.

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ABSTRACT A Lewis acid–promoted nucleophilic addition of methallyltrimethylsilane to a chiral α-keto imide proceeded with stereoselectivity opposite to that predicted from Soai's report. The difference in the structure of α-keto imides between Soai's and our cases might have affected the diastereofacial selectivity.

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27

Ramasamy, Manickavasakam, Hui-Chang Lin, Sheng-Chu Kuo та Min-Tsang Hsieh. "Lewis Acid-Catalyzed Rearrangement of Fluoroalkylated Propargylic Alcohols: An Alternative Approach to β-Fluoroalkyl-α,β-enones". Synlett 30, № 03 (2019): 356–60. http://dx.doi.org/10.1055/s-0037-1611694.

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A practical Lewis acid-catalyzed Meyer–Schuster rearrangement of fluoroalkylated propargylic alcohols, leading to a series of β-fluoroalkyl-α,β-enones, is developed. The methodology reported herein features moderate to high yields and high stereoselectivity in the synthesis of β-alkyl-β-fluoroalkyl-α,β-enones.

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28

Chen, Qijia, Xi Chen, Yunfeng Cui та ін. "A newd-threonine aldolase as a promising biocatalyst for highly stereoselective preparation of chiral aromatic β-hydroxy-α-amino acids". Catalysis Science & Technology 7, № 24 (2017): 5964–73. http://dx.doi.org/10.1039/c7cy01774j.

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29

Chen, Kai, Xi Gao, Hui Zou, Guan Xiao та Xin Peng. "Copper-Catalyzed Direct α-Nitration of Nitrostilbenes with Nitrogen Dioxide". Synlett 30, № 07 (2019): 833–36. http://dx.doi.org/10.1055/s-0037-1611749.

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A novel and efficient method for the direct α-nitration of nitrostilbenes was developed in which NO2 was used as the nitro source. This method provided (E)-α-nitrostilbenes derivatives in moderate to good yields. A broad substrate scope, mild and convenient conditions, and high stereoselectivity are important features of this method.

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30

Song, Liyan, Xinqiang Fang, Zijia Wang, Kun Liu та Chaozhong Li. "Stereoselectivity of 6-Exo Cyclization of α-Carbamoyl Radicals". Journal of Organic Chemistry 81, № 6 (2016): 2442–50. http://dx.doi.org/10.1021/acs.joc.6b00008.

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31

Sinisterra, José Vicente, Emilio Fidel Llama, Carmen del Campo, María José Cabezas, José María Moreno та Miguel Arroyo. "Stereoselectivity of chemically modified α-chymotrypsin and immobilized lipases". J. Chem. Soc., Perkin Trans. 2, № 6 (1994): 1333–36. http://dx.doi.org/10.1039/p29940001333.

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32

Armstrong, Susan K., Eric W. Collington, Jon Stonehouse та Stuart Warren. "On the stereoselectivity of nitrone addition to α-diphenylphosphinoylalkenes". J. Chem. Soc., Perkin Trans. 1, № 19 (1994): 2825–31. http://dx.doi.org/10.1039/p19940002825.

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33

ARMSTRONG, S. K., E. W. COLLINGTON, J. STONEHOUSE та S. WARREN. "ChemInform Abstract: Stereoselectivity of Nitrone Addition to α- Diphenylphosphinoylalkenes." ChemInform 26, № 15 (2010): no. http://dx.doi.org/10.1002/chin.199515212.

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34

Iseki, Katsuhiko, Satoshi Oishi, Takeo Taguchi та Yoshiro Kobayashi. "Reversal of stereoselectivity in the Evans aldol reaction of α,α-difluoro and α,α,α-trifluoro carbonyl compounds". Tetrahedron Letters 34, № 50 (1993): 8147–50. http://dx.doi.org/10.1016/s0040-4039(00)61475-2.

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35

Iseki, Katsuhiko, Satoshi Oishi та Yoshiro Kobayashi. "Reversal of stereoselectivity in the Evans aldol reaction of α,α-difluoro and α,α,α-trifluoro carbonyl compounds". Tetrahedron 52, № 1 (1996): 71–84. http://dx.doi.org/10.1016/0040-4020(95)00858-6.

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36

Yang, Yuanfa, Lina Wang, Jieni Zhang, Yali Jin, and Gangguo Zhu. "An unprecedented Pd-catalyzed trans-addition of boronic acids to ynamides." Chem. Commun. 50, no. 18 (2014): 2347–49. http://dx.doi.org/10.1039/c3cc49069f.

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37

Ouled Aitouna, Abdelhak, Lahoucine Bahsis, Hicham Ben El Ayouchia, Ahmed Chekroun, Redouan Hammal та Ahmed Benharref. "A DFT reinvestigation of chemo- and stereoselectivity epoxidation from α- and ɣ-trans himachalene with meta Chloroperoxybenzoic acid". Mediterranean Journal of Chemistry 9, № 2 (2019): 133–41. http://dx.doi.org/10.13171/mjc92190919645aoa/hbe.

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In this work the epoxidation reaction of the α- and ɣ-trans himachalene in the presence of meta chloroperoxybenzoic acid (m-CPBA) has been studied within the Density Functional Theory (DFT) method at the B3LYP/6-311G(d,p) level in dichloromethane as a solvent, in order to shed light on the chemo- and stereoselectivity in the course of the reaction. Analysis of the Conceptual Density Functional Theory (CDFT) reactivity indices indicate that the m-CPBA will behave as electrophilic while α- and ɣ-trans himachalene will behave as a nucleophile and the attacks observed experimentally are correctly

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38

Ren, Wei, Ming Jin, Qian-Ming Zuo та Shang-Dong Yang. "Allylation of β-amino phosphonic acid precursor via palladium-NHC catalyzed allylic C–H activation". Organic Chemistry Frontiers 7, № 2 (2020): 298–302. http://dx.doi.org/10.1039/c9qo01089k.

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A Pd(ii)/N-heterocyclic carbene (NHC) catalyzed allylic C–H alkylation of allylbenzene with α-cyano-phosphate ester has been achieved under mild reaction conditions with the highest regioselectivity and stereoselectivity.

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39

Yang, Desuo, Xiaolin Luo, Haiyun Zhu, Yaning Guo та Longmin Wu. "Studies on the reaction of nitric oxide with α,β-unsaturated hydrazones". Canadian Journal of Chemistry 90, № 6 (2012): 510–16. http://dx.doi.org/10.1139/v2012-022.

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α,β-Unsaturated arylhydrazones (1) reacted with nitric oxide (NO) in the presence of a trace of oxygen to give α- (2a–2c, 2e, and 2f) or β-nitro (2d and 2g) unsaturated hydrazones in good yield and with high stereoselectivity. The reaction occurs most likely by an electrophilic addition of NO2 to the carbon–carbon double bond of 1 at its α- or β-position.

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40

Karahan, Seda, та Cihangir Tanyeli. "Bifunctional squaramide catalyzed stereoselective Mannich reaction of α-azido ketones with isatin-derived ketimines". Organic & Biomolecular Chemistry 18, № 3 (2020): 479–87. http://dx.doi.org/10.1039/c9ob02208b.

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Bifunctional squaramide catalyzed asymmetric Mannich reaction of alpha-azido ketones and isatin derived ketiminines were established for the first time with high stereoselectivity. Adducts are valuable synthons for optically active heterocycles.

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41

Meninno, Sara, Simone Naddeo, Luca Varricchio, Amedeo Capobianco та Alessandra Lattanzi. "Stereoselective organocatalytic sulfa-Michael reactions of aryl substituted α,β-unsaturated N-acyl pyrazoles". Organic Chemistry Frontiers 5, № 12 (2018): 1967–77. http://dx.doi.org/10.1039/c8qo00357b.

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A variety of functionalised sulfides has been obtained in good to high stereoselectivity via sulfa-Michael reaction of α,β-unsaturated N-acyl pyrazoles with thiols or thioacetic acid using readily available organocatalysts and working under mild conditions.

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42

Bell, KH, та G. Fullick. "Synthesis, Absolute Configuration and Local Anaesthetic Activity of the Enantiomers of α- and Β-Methylprocaine". Australian Journal of Chemistry 38, № 9 (1985): 1429. http://dx.doi.org/10.1071/ch9851429.

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Optically active forms of 1-( diethylaminomethyl )ethyl 4-aminobenzoate (α- methylprocaine ) (1) and 2-( diethylamino ) propyl 4-aminobenzoate (β- methylprocaine ) (2) of known absolute configuration have been prepared. The enantiomers show no stereoselectivity in conduction or infiltration anaesthesia.

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43

Cole, Charles J. F., Lilia Fuentes, and Scott A. Snyder. "Asymmetric pyrone Diels–Alder reactions enabled by dienamine catalysis." Chemical Science 11, no. 8 (2020): 2175–80. http://dx.doi.org/10.1039/c9sc05738b.

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A dienamine mediated asymmetric Diels–Alder reaction between an array of α,β-unsaturated enals and electron-deficient pyrones is presented along with further transformations of the obtained products and models for the observed stereoselectivity.

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44

Yepes, Diana, Patricia Pérez, Pablo Jaque та Israel Fernández. "Effect of Lewis acid bulkiness on the stereoselectivity of Diels–Alder reactions between acyclic dienes and α,β-enals". Organic Chemistry Frontiers 4, № 7 (2017): 1390–99. http://dx.doi.org/10.1039/c7qo00154a.

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45

Bera, Kalisankar, Narasimham Ayyagari, Nishikant Satam та Irishi N. N. Namboothiri. "Stereoselective synthesis of hydrazinodihydrofurans via cascade Michael addition–substitution involving the reaction of curcumin and other β-dicarbonyls with α-hydrazinonitroalkenes". Organic & Biomolecular Chemistry 18, № 1 (2020): 140–53. http://dx.doi.org/10.1039/c9ob01974j.

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Reaction of 1,3-dicarbonyls with α-hydrazinonitroalkenes leads to 2-hydrazino-2,3-dihydrofurans with high stereoselectivity in the presence of a tert-leucine derived squaramide and K<sub>2</sub>CO<sub>3</sub> in aqueous THF.

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46

Chan, T. H., and C. J. Li. "A concise synthesis of (+)-muscarine." Canadian Journal of Chemistry 70, no. 11 (1992): 2726–29. http://dx.doi.org/10.1139/v92-346.

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(+)-Muscarine was synthesized from S-(−)-ethyl lactate in five steps with the application of a zinc-mediated allylation reaction in aqueous media. Reversal of chelation-control stereoselectivity was observed in the allylations of chiral α-alkoxy aldehydes in aqueous media.

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47

O’Connor, Matthew, Huaqing Liu, Daesung Lee, Tao Zhou та Yuanzhi Xia. "DFT Studies on the Stereoselectivity of α-Silyloxy Diazoalkane Cycloadditions". Molecules 20, № 12 (2015): 21433–41. http://dx.doi.org/10.3390/molecules201219783.

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48

Honda, Kazuo, Chieko Nakagawa, Toichi Takenaka та Michio Terai. "Stereoselectivity in YM-12617 for α-adrenoceptor subtypes in vitro". Japanese Journal of Pharmacology 40 (1986): 180. http://dx.doi.org/10.1016/s0021-5198(19)59286-1.

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49

Krenske, Elizabeth H., K. N. Houk, Daniel Lim, Sarah E. Wengryniuk та Don M. Coltart. "Origins of Stereoselectivity in the α-Alkylation of Chiral Hydrazones". Journal of Organic Chemistry 75, № 24 (2010): 8578–84. http://dx.doi.org/10.1021/jo1019877.

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50

Hou, Shu-jie, та Pavol Kováč. "Enhanced stereoselectivity of α-mannosylation under thermodynamic control using trichloroacetimidates". Carbohydrate Research 345, № 8 (2010): 999–1007. http://dx.doi.org/10.1016/j.carres.2010.03.025.

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