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Chiral Symmetric Alkylamides of Phosphoric and Phosphonic Acids
Phosphorus, Sulfur, and Silicon and the Related Elements, 2002(2002). Chiral Symmetric Alkylamides of Phosphoric and Phosphonic Acids. Phosphorus, Sulfur, and Silicon and the Related Elements: Vol. 177, No. 8-9, pp. 2109-2110.
Oleg I. Kolodiazhnyi, Natalia Andruschko
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The preparation and reactions of chiral phosphorous acid diamides
Tetrahedron Letters, 1991Abstract Chiral phosphorous acid diamides were prepared by condensation of N,N′-disubstituted C 2 diamines with PCl 3 followed by an equivalent of water. Deprotonation of these acids with n-butyl lithium or LDA gave the lithium salt which reacted smoothly with alkyl halides to give the substituted phosphonamides in good yield.
Kevin J. Koeller +1 more
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Synthesis of chiral amino cyclic phosphoric acids
Wuhan University Journal of Natural Sciences, 2000Chiral amino cyclic phosphoric acids, 5-amino-2-hydroxy-4-(4-nitrophenyl)-1,3,2-dioxaphosphorinane 2-oxide and 2-hydroxy-4-(4-methylsulfonylphenyl)-5-phthalimido-1,3,2-dioxaphos phorinane 2-oxide are synthesized in good over yields (64.2% and 72.8% respectively) from 2-amino-1-aryl-1,3-propanediols.
Zhang Zhan +5 more
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Chiral Phosphoric Acid Catalyzed Stereoselective Spiroketalizations
Synlett, 2013The spiroketal functionality is an important structural motif present in numerous natural products. The synthesis of chiral spiroketals is typically achieved under equilibrating conditions and only few asymmetric approaches are known. We have demonstrated that chiral phosphoric acids (CPAs) could serve as effective catalysts for enantioselective ...
Pavel Nagorny +2 more
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Angewandte Chemie, 2020
AbstractA new chiral Brønsted acid, generated in situ from a chiral phosphoric acid boron (CPAB) complex and water, was successfully applied to asymmetric indole reduction. This “designer acid catalyst”, which is more acidic than TsOH as suggested by DFT calculations, allows the unprecedented direct asymmetric reduction of C2‐aryl‐substituted N ...
Kai Yang +11 more
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AbstractA new chiral Brønsted acid, generated in situ from a chiral phosphoric acid boron (CPAB) complex and water, was successfully applied to asymmetric indole reduction. This “designer acid catalyst”, which is more acidic than TsOH as suggested by DFT calculations, allows the unprecedented direct asymmetric reduction of C2‐aryl‐substituted N ...
Kai Yang +11 more
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Development and application of chiral spirocyclic phosphoric acids in asymmetric catalysis
Organic & Biomolecular Chemistry, 2018This review describes the synthetic methods for the preparation of chiral spirocyclic phosphoric acids (SPAs), and their dynamically developing application for catalytic enantioselective transformations.
Abdul Rahman, Xufeng Lin
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The first catalytic asymmetric thioacetalization by chiral phosphoric acid catalysis
Organic & Biomolecular Chemistry, 2016We report here the first catalytic asymmetric thioacetalization of salicylaldehyde and dithiol. Chiral phosphoric acid STRIPC5is identified as a powerful catalyst for this reaction to afford various chiral dithioacetals in high to excellent yields and enantioselectivities under mild conditions.
Jin-Sheng, Yu, Wen-Biao, Wu, Feng, Zhou
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Enantioselective Aza-Darzens Reaction Catalyzed by A Chiral Phosphoric Acid
Organic Letters, 2009Aza-Darzens reaction of ethyl diazoacetate with aldimines, derived from phenyl glyoxal, furnished cis-aziridine carboxylates with excellent enantioselectivities by means of a chiral phosphoric acid.
Takahiko, Akiyama +2 more
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A Protecting‐Group‐Free Route to Chiral BINOL–Phosphoric Acids
European Journal of Organic Chemistry, 2011AbstractA two‐step, protecting group‐free route for the synthesis of 3,3′‐disubstituted and 6,6′‐disubstituted chiral BINOL–phosphoric acids has been realized starting from commercially available brominated BINOLs. This synthesis relies on the direct Suzuki coupling of brominated BINOL phosphoric acids.
Li, B, Chiu, P
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Synthesis and Evaluation of 5,5′-Bitetralone-Based Chiral Phosphoric Acids
Organic Letters, 2015A new type of phosphoric acid bearing a 5,5'-bitetralone scaffold was synthesized from BINOL and was shown to be a highly effective catalyst as illustrated in the asymmetric transfer hydrogenation of 2-phenylquinoline and the Friedel-Crafts reaction of 2,2,2-trifluoroacetophenone.
Yazhou, Wang +3 more
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