Chiral Amino Alcohols via Catalytic Enantioselective Petasis Borono-Mannich Reactions

Chiral amino alcohols are valuable building blocks in the synthesis of drugs, natural products, and chiral ligands used in enantioselective catalysis. The Petasis borono-Mannich reaction is a multicomponent condensation reaction of aldehydes, amines, and boronic acids to afford chiral amines. This report describes a practical, easily scaled, enantioselective Petasis borono-Mannich reaction of glycolaldehyde, with primary or secondary amines, and boronates catalyzed by BINOLderived catalysts to afford chiral 1,2-amino alcohols in high yields and enantioselectivities. The reactions are executed at room temperature in ethanol or trifluorotoluene using commercially available reagents and leverage an inherently attractive feature of the multicomponent reaction; the ability to use amines and boronates that possess a wide range of structural and electronic properties. Computational modeling of the diastereomeric transition states using DFT calculations identified a non-conventional CH…O interaction as a key feature that selectively stabilizes the transition state leading to the major enantiomer. The enantioselective catalytic reaction exemplifies a truly practical multicomponent condensation to afford 1,2-amino alcohols in highly enantioenriched form.

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Stereospecific, Palladium-catalyzed C(sp3)–H Alkenylation and Alkynylation of a Proline Derivative Enabled by 8-Aminoquinoline as a Directing Group

10.26434/chemrxiv.12034743 ◽

2020 ◽

Author(s):

Aleksandra Balliu ◽

Aaltje Roelofje Femmigje Strijker ◽

Michael Oschmann ◽

Monireh Pourghasemi Lati ◽

Oscar Verho

Keyword(s):

Carboxylic Acid ◽

Building Blocks ◽

Wide Range ◽

Palladium Catalyzed ◽

Directing Group ◽

High Yields ◽

Vinyl Iodides ◽

Initial Results

In this preprint, we present our initial results concerning a stereospecific Pd-catalyzed protocol for the C3 alkenylation and alkynylation of a proline derivative carrying the well utilized 8‑aminoquinoline directing group. Efficient C–H alkenylation was achieved with a wide range of vinyl iodides bearing different aliphatic, aromatic and heteroaromatic substituents, to furnish the corresponding C3 alkenylated products in good to high yields. In addition, we were able show that this protocol can also be used to install an alkynyl group into the pyrrolidine scaffold, when a TIPS-protected alkynyl bromide was used as the reaction partner. Furthermore, two different methods for the removal of the 8-aminoquinoline auxiliary are reported, which can enable access to both cis- and trans-configured carboxylic acid building blocks from the C–H alkenylation products.

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Applications of tert-butanesulfinamide in the asymmetric synthesis of amines

Pure and Applied Chemistry ◽

10.1351/pac200375010039 ◽

2003 ◽

Vol 75 (1) ◽

pp. 39-46 ◽

Cited By ~ 181

Author(s):

J. A. Ellman

Keyword(s):

Amino Acids ◽

Asymmetric Synthesis ◽

Nucleophilic Addition ◽

Amino Alcohols ◽

Wide Range ◽

Aldehydes And Ketones ◽

Directing Group ◽

High Yields ◽

Direct Condensation

tert-Butanesulfinamide is prepared using catalytic enantioselective methods in two steps from the extremely inexpensive oil waste by-product, tert-butyl disulfide. Direct condensation of tert-butanesulfinamide with aldehydes and ketones provides tert-butanesulfinyl imines in uniformly high yields. The tert-butanesulfinyl group activates the imines for the addition of many different classes of nucleophiles, serves as a powerful chiral directing group, and after nucleophilic addition is readily cleaved by treatment with acid. A wide range of highly enantioenriched amines, including α-branched and α,α-dibranched amines, α- and β-amino acids, 1,2 and 1,3-amino alcohols and α-trifluoromethyl amines are efficiently synthesized using this methodology.

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The Discovery of Ultrasound Irradiation as a Useful Tool for Accelerating Petasis Three-component Reaction: Synthesis of α-Arylglycines

Current Organic Synthesis ◽

10.2174/1570179414666170821115834 ◽

2018 ◽

Vol 15 (2) ◽

pp. 256-266 ◽

Cited By ~ 2

Author(s):

Fan Yun ◽

Chunhui Cheng ◽

Jingxuan Li ◽

Pingwah Tang ◽

Qipeng Yuan

Keyword(s):

Reaction Time ◽

Glyoxylic Acid ◽

Reaction Times ◽

Ultrasound Irradiation ◽

Secondary Amines ◽

One Pot ◽

Petasis Reaction ◽

Three Component Reaction ◽

Wide Range ◽

High Yields

Aim and Objective: α-Arylglycines belong to an important class of non-proteinogenic amino acids. Petasis 3-component, one-pot reaction lends itself to be suitable for the synthesis of α-Arylglycines. Because of the low reactivity, Petasis reaction requires long reaction time. Our objective is to use ultrasound irradiation to accelerate this versatile Petasis' synthesis of α-Arylglycines. Materials and Methods: Ultrasound irradiation as a physical tool to accelerate the Petasis 3-component reaction without any auxiliary catalyst can significantly shorten the reaction time. The operation is simple. It can be applied to a wide range of substrates. In order to highlight the remarkable utility of the ultrasound in Petasis reaction, we have compared side-by-side the reactivity between the reaction with ultrasound and the one without ultrasound. Results: Using ultrasound, the reaction times of Petasis reactions with various amine substrates including primary and secondary amines, heterocyclic amines, with a wide variety of boronic acids having different substituents (activating and deactivating groups) in the phenyl rings, and with glyoxylic acid and salicylic aldehyde were shortened from 5 to more than 20-fold. Conclusion: We have discovered the first examples of an efficient ultrasound-promoted approach for Petasis reaction to prepare a series of α-arylglycines in high yields and in excellent purities. The low reactivity of the reactions in this study were significantly enhanced by the ultrasound irradiation. By virtue of the acceleration and the operational simplicity, the present ultrasound assisted Petasis reaction can find applications in the synthetic areas of the already widely used Petasis three-component reaction.

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Multicomponent Reactions, Solvent-Free Synthesis of 2-Amino-4-aryl-6-substituted Pyridine-3,5-dicarbonitrile Derivatives, and Corrosion Inhibitors Evaluation

Journal of Chemistry ◽

10.1155/2018/7958739 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

Naglaa F. H. Mahmoud ◽

Ahmed El-Sewedy

Keyword(s):

Aromatic Aldehydes ◽

Primary Amines ◽

One Pot ◽

Multicomponent Condensation ◽

Wide Range ◽

Elemental Analyses ◽

High Yields ◽

New Compounds ◽

First Time ◽

Solvent Free Synthesis

A number of 2-amino-4-aryl-6-substituted pyridine-3,5-dicarbonitrile derivatives were synthesized via one-pot multicomponent condensation reactions of different aromatic aldehydes with malononitrile and different primary amines, using different molecular ratios and different reaction conditions to achieve considerable product yields. Moreover, we succeed, for the first time to develop a new method to synthesize the aforementioned under the fusion condition without using solvent and catalysts. With this method, a wide range of novel 2-amino-3,5-dicyano-4-aryl-6-substituted aminopyridine derivatives were synthesized with high yields and board substrate of functional groups. The synthesized pyridine derivatives were found to have a corrosion inhibition efficiency, the rate of which increased with the increasing concentration of the derivatives. The structures of the new compounds were elucidated by spectroscopic data and elemental analyses.

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Stereospecific, Palladium-catalyzed C(sp3)–H Alkenylation and Alkynylation of a Proline Derivative Enabled by 8-Aminoquinoline as a Directing Group

10.26434/chemrxiv.12034743.v1 ◽

2020 ◽

Author(s):

Aleksandra Balliu ◽

Aaltje Roelofje Femmigje Strijker ◽

Michael Oschmann ◽

Monireh Pourghasemi Lati ◽

Oscar Verho

Keyword(s):

Carboxylic Acid ◽

Building Blocks ◽

Wide Range ◽

Palladium Catalyzed ◽

Directing Group ◽

High Yields ◽

Vinyl Iodides ◽

Initial Results

In this preprint, we present our initial results concerning a stereospecific Pd-catalyzed protocol for the C3 alkenylation and alkynylation of a proline derivative carrying the well utilized 8‑aminoquinoline directing group. Efficient C–H alkenylation was achieved with a wide range of vinyl iodides bearing different aliphatic, aromatic and heteroaromatic substituents, to furnish the corresponding C3 alkenylated products in good to high yields. In addition, we were able show that this protocol can also be used to install an alkynyl group into the pyrrolidine scaffold, when a TIPS-protected alkynyl bromide was used as the reaction partner. Furthermore, two different methods for the removal of the 8-aminoquinoline auxiliary are reported, which can enable access to both cis- and trans-configured carboxylic acid building blocks from the C–H alkenylation products.

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Microwave-assisted Aminolysis of Epoxides under Solvent-free Conditions Catalyzed by Montmorillonite Clay

Journal of Chemical Research ◽

10.1177/174751989902300231 ◽

1999 ◽

Vol 23 (2) ◽

pp. 128-129

Author(s):

Mohammad M. Mojtahedi ◽

Mohammad R. Saidi ◽

Mohammad Bolourtchian

Keyword(s):

Microwave Irradiation ◽

Amino Alcohols ◽

Solvent Free ◽

Montmorillonite Clay ◽

Secondary Amines ◽

Microwave Assisted ◽

Montmorillonite K10 ◽

Solvent Free Conditions ◽

Primary And Secondary Amines ◽

High Yields

The reaction of primary and secondary amines with epoxides in the presence of montmorillonite K10 clay, under solvent-free condtions and microwave irradiation affords high yields of β-amino alcohols.

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ChemInform Abstract: New Chiral Building Blocks and Their Application to the Construction of Chiral Amino Alcohols: Enantiomerically Pure cis- and trans-3- Mesyloxy-4-hydroxy Tetrahydrofurans.

ChemInform ◽

10.1002/chin.199401184 ◽

2010 ◽

Vol 25 (1) ◽

pp. no-no

Author(s):

A. BOERNER ◽

J. HOLZ ◽

H. B. KAGAN

Keyword(s):

Building Blocks ◽

Amino Alcohols ◽

Enantiomerically Pure ◽

Cis And Trans ◽

Chiral Amino Alcohols

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On the Search of a Silver Bullet for the Preparation of Bioinspired Molecular Electrets with Propensity to Transfer Holes at High Potentials

Biomolecules ◽

10.3390/biom11030429 ◽

2021 ◽

Vol 11 (3) ◽

pp. 429

Author(s):

James Bennett Derr ◽

Katarzyna Rybicka-Jasińska ◽

Eli Misael Espinoza ◽

Maryann Morales ◽

Mimi Karen Billones ◽

...

Keyword(s):

Free Acid ◽

Building Blocks ◽

Butyl Ether ◽

One Pot ◽

Nitrobenzoic Acid ◽

Wide Range ◽

High Potentials ◽

Scalable Synthesis ◽

High Yields ◽

Derivatives Of

Biological structure-function relationships offer incomparable paradigms for charge-transfer (CT) science and its implementation in solar-energy engineering, organic electronics, and photonics. Electrets are systems with co-directionally oriented electric dopes with immense importance for CT science, and bioinspired molecular electrets are polyamides of anthranilic-acid derivatives with designs originating from natural biomolecular motifs. This publication focuses on the synthesis of molecular electrets with ether substituents. As important as ether electret residues are for transferring holes under relatively high potentials, the synthesis of their precursors presents formidable challenges. Each residue in the molecular electrets is introduced as its 2-nitrobenzoic acid (NBA) derivative. Hence, robust and scalable synthesis of ether derivatives of NBA is essential for making such hole-transfer molecular electrets. Purdie-Irvine alkylation, using silver oxide, produces with 90% yield the esters of the NBA building block for iso-butyl ether electrets. It warrants additional ester hydrolysis for obtaining the desired NBA precursor. Conversely, Williamson etherification selectively produces the same free-acid ether derivative in one-pot reaction, but a 40% yield. The high yields of Purdie-Irvine alkylation and the selectivity of the Williamson etherification provide important guidelines for synthesizing building blocks for bioinspired molecular electrets and a wide range of other complex ether conjugates.

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Quasi Pd1Ni single-atom surface alloy catalyst enables hydrogenation of nitriles to secondary amines

Nature Communications ◽

10.1038/s41467-019-12993-x ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 16

Author(s):

Hengwei Wang ◽

Qiquan Luo ◽

Wei Liu ◽

Yue Lin ◽

Qiaoqiao Guan ◽

...

Keyword(s):

Building Blocks ◽

Surface Alloy ◽

Secondary Amines ◽

Single Atom ◽

Redox Potentials ◽

Practical Applications ◽

Mild Conditions ◽

Metal Selectivity ◽

High Yields ◽

Hydrogenation Of Nitriles

Abstract Hydrogenation of nitriles represents as an atom-economic route to synthesize amines, crucial building blocks in fine chemicals. However, high redox potentials of nitriles render this approach to produce a mixture of amines, imines and low-value hydrogenolysis byproducts in general. Here we show that quasi atomic-dispersion of Pd within the outermost layer of Ni nanoparticles to form a Pd1Ni single-atom surface alloy structure maximizes the Pd utilization and breaks the strong metal-selectivity relations in benzonitrile hydrogenation, by prompting the yield of dibenzylamine drastically from ∼5 to 97% under mild conditions (80 °C; 0.6 MPa), and boosting an activity to about eight and four times higher than Pd and Pt standard catalysts, respectively. More importantly, the undesired carcinogenic toluene by-product is completely prohibited, rendering its practical applications, especially in pharmaceutical industry. Such strategy can be extended to a broad scope of nitriles with high yields of secondary amines under mild conditions.

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