scholarly journals A Short Approach to N-Aryl-1,2,3,4-tetrahydroisoquinolines from N-(2-Bromobenzyl)anilines via a Reductive Amination/Palladium-Catalyzed Ethoxyvinylation/Reductive N-Alkylation Sequence

Synthesis ◽  
2021 ◽  
Author(s):  
Franz Bracher ◽  
Carina Glas ◽  
Ricky Wirawan
Keyword(s):  
Aromatic Amines ◽  
Reductive Amination ◽  
Functional Group ◽  
Aromatic Aldehydes ◽  
Building Blocks ◽  
Aromatic Rings ◽  
Palladium Catalyzed ◽  
Primary Aromatic Amines

Abstract N-Aryl-1,2,3,4-tetrahydroisoquinolines are obtained via a convenient and short protocol with a broad range of substituents on both aromatic rings and high functional group tolerance. Starting from readily available ortho-brominated aromatic aldehydes and primary aromatic amines, condensation of these building blocks under reductive conditions gives N-aryl 2-bromobenzylamines. The C-3/C-4-unit of the tetrahydroisoquinoline is introduced using commercially available 2-ethoxyvinyl pinacolboronate under Suzuki conditions. Finally, the obtained crude ortho-ethoxyvinyl benzylamines are cyclized via an intramolecular reductive amination using the combination of triethylsilane/TFA to give the desired N-aryl-1,2,3,4-tetrahydroisoquinolines.

Cyclisation of 1-Phenyl-4-carboxymethylmercapto-5-arylazo-hydantoins

1981 ◽  
Vol 36 (4) ◽  
pp. 501-504 ◽  
Author(s):  
A. F. A. Shalaby ◽  
M. A. Abdel Aziz ◽  
S. S. M. Boghdadi
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Aromatic Amines ◽  
Sodium Acetate ◽  
Aromatic Aldehydes ◽  
Mannich Bases ◽  
Anhydrous Sodium Acetate ◽  
Primary Aromatic Amines ◽  
Hydantoin Derivatives

Abstract 1-Phenyl-4-carboxymethylmercapto-5-arylazo-hydantoin derivatives (3a-f) were cyclised with acetic anhydride to give the bicyclic products (4a-f). Compounds 4 a, b condensed with aromatic aldehydes in acetic acid and in presence of anhydrous sodium acetate yielding the corresponding arylidene derivatives (5a-c). Compounds 4a, b also couple with aryldiazonium salts to give the expected coloured arylazo compounds (6a-j). 4 a, b reacted with formaldehyde and primary aromatic amines in ethanol to give the corresponding Mannich bases (7a-f).

scholarly journals Synthesis, Characterization and Evaluate the Biological Activity of Novel Heterocyclic Derivatives from Azomethine Compounds

2019 ◽  
Vol 35 (4) ◽  
pp. 1360-1367
Author(s):  
Rasim Farraj Muslim ◽  
Suheb Eaid Saleh
Keyword(s):  
Biological Activity ◽  
Aromatic Amines ◽  
Aromatic Aldehydes ◽  
The Novel ◽  
Heterocyclic Derivatives ◽  
Primary Aromatic Amines ◽  
Ft Ir ◽  
Bacteria And Fungi ◽  
Azomethine Compounds

This research includes synthesis of new seventh-membered heterocyclic derivatives as 1,3-oxazepine-dione derived from azomethine compounds. Azomethine compounds R1-R4 were synthesized by the reaction of aromatic aldehydes with primary aromatic amines. The novel of 1,3-oxazepine-dione derivatives R5-R9 were obtained from the treatment of azomethine compounds with anhydrides. The synthesized compounds were checked by TLC technique, spectral methods (FT-IR, H1-NMR) and measurements of some its physical properties. The biological activity of the heterocyclic derivatives was investigated against bacteria and fungi in vitro.

scholarly journals Ligand-Controlled Regiodivergent Palladium-Catalyzed Hydrogermylation of Ynamides

2020 ◽  
Author(s):  
Vincent Debrauwer ◽  
Aneta Turlik ◽  
Lénaïc Rummler ◽  
Alessandro Prescimone ◽  
Nicolas Blanchard ◽  
...  
Keyword(s):  
Small Molecules ◽  
Functional Group ◽  
Cross Coupling ◽  
Building Blocks ◽  
Coupling Reactions ◽  
Heterocyclic Chemistry ◽  
Cross Coupling Reactions ◽  
Palladium Catalyzed ◽  
Metal Catalyzed ◽  
Pi System

Ynamides are fascinating small molecules with complementary reactivities under radical, ionic and metal-catalyzed conditions. We report herein synthetic and DFT investigations of palladium-catalyzed ligand-controlled regiodivergent hydro-metallation reactions of ynamides. Germylated and stannylated enamides are obtained with excellent alpha,<i>E</i>- or beta,<i>E</i>-selectivities and a broad functional group tolerance. Such a regiodivergent palladium-catalyzed process is unique in ynamide chemistry and allows for the elaboration of metallated-enamides that are useful building blocks for cross-coupling reactions or heterocyclic chemistry. DFT calculations fully support the experimental data and demonstrate the crucial roles of the <i>trans</i>-geometry of the [H-Pd(L)-Ge] complex, as well as of the steric requirements of the phosphine ligand. In addition, the prevalence of a hydro-palladation pathway over a metal-palladation of the pi system of the ynamide was demonstrated.

scholarly journals Palladium-catalyzed amination of 2-chlorothienopyridone with primary aromatic amines

2019 ◽  
Vol 5 (1) ◽  
pp. 1567894
Author(s):  
Samir A. Al-Taweel ◽  
Salah A. Al-Trawneh ◽  
Wal'A M. Al-Trawneh ◽  
Cindy Browder
Keyword(s):  
Aromatic Amines ◽  
Palladium Catalyzed ◽  
Primary Aromatic Amines

Hitchhiker’s Guide to Reductive Amination

Synthesis ◽  
2019 ◽  
Vol 51 (13) ◽  
pp. 2667-2677 ◽  
Author(s):  
Evgeniya Podyacheva ◽  
Oleg I. Afanasyev ◽  
Alexey A. Tsygankov ◽  
Maria Makarova ◽  
Denis Chusov
Keyword(s):  
Green Chemistry ◽  
Comparative Study ◽  
Aromatic Amines ◽  
Reductive Amination ◽  
Aromatic Aldehydes ◽  
Reducing Agents ◽  
Aldehydes And Ketones

A comparative study of various widely used methods of reductive amination is reported. Specifically, such reducing agents as H2, Pd/C, hydride reagents [NaBH4, NaBH3CN, NaBH(OAc)3], and CO/Rh2(OAc)4 system were considered. For understanding the selectivity and activity of the reducing agents reviewed herein, different classes of starting materials were tested, including aliphatic and aromatic amines, as well as aliphatic and aromatic aldehydes and ketones. Most important advantages and drawbacks of the methods, such as selectivity of the target amine formation and toxicity of the reducing agents were compared. Methods were also considered from the viewpoint of green chemistry.

scholarly journals Potential-tuned selective electrosynthesis of azoxy-, azo- and amino-aromatics over a CoP nanosheet cathode

2019 ◽  
Vol 7 (2) ◽  
pp. 285-295 ◽  
Author(s):  
Xiaodan Chong ◽  
Cuibo Liu ◽  
Yi Huang ◽  
Chenqi Huang ◽  
Bin Zhang
Keyword(s):  
Green Synthesis ◽  
Aromatic Amines ◽  
Functional Group ◽  
Materials Science ◽  
Selective Reduction ◽  
Building Blocks ◽  
Deuterium Content ◽  
High Yields ◽  
A Current ◽  
Excellent Selectivity

Abstract Azoxy-, azo- and amino-aromatics are among the most widely used building blocks in materials science pharmaceuticals and synthetic chemistry, but their controllable and green synthesis has not yet been well established. Herein, a facile potential-tuned electrosynthesis of azoxy-, azo- and amino-aromatics via aqueous selective reduction of nitroarene feedstocks over a CoP nanosheet cathode is developed. A series of azoxy-, azo- and amino-compounds with excellent selectivity, good functional group tolerance and high yields are produced by applying different bias input. The synthetically significant and challenging asymmetric azoxy-aromatics can be controllably synthesized in moderate to good yields. The use of water as the hydrogen source makes this strategy remarkably fascinating and promising. In addition, deuterated aromatic amines with a high deuterium content can be readily obtained by using D2O. By pairing with anodic oxidation of aliphatic amines to nitriles, synthetically useful building blocks can be simultaneously produced in a CoP||Ni2P two-electrode electrolyzer. Only 1.25 V is required to achieve a current density of 20 mA cm−2, which is much lower than that of overall water splitting (1.70 V). The paired oxidation and reduction reactions can also be driven using a 1.5 V battery to synthesize nitrile and azoxybenzene with good yields and selectivity, further emphasizing the flexibility and controllability of our method. This work paves the way for a promising approach to the green synthesis of valuable chemicals through potential-controlled electrosynthesis.

scholarly journals Ligand-Controlled Regiodivergent Palladium-Catalyzed Hydrogermylation of Ynamides

2020 ◽  
Author(s):  
Vincent Debrauwer ◽  
Aneta Turlik ◽  
Lénaïc Rummler ◽  
Alessandro Prescimone ◽  
Nicolas Blanchard ◽  
...  
Keyword(s):  
Small Molecules ◽  
Functional Group ◽  
Cross Coupling ◽  
Building Blocks ◽  
Coupling Reactions ◽  
Heterocyclic Chemistry ◽  
Cross Coupling Reactions ◽  
Palladium Catalyzed ◽  
Metal Catalyzed ◽  
Pi System

Ynamides are fascinating small molecules with complementary reactivities under radical, ionic and metal-catalyzed conditions. We report herein synthetic and DFT investigations of palladium-catalyzed ligand-controlled regiodivergent hydro-metallation reactions of ynamides. Germylated and stannylated enamides are obtained with excellent alpha,<i>E</i>- or beta,<i>E</i>-selectivities and a broad functional group tolerance. Such a regiodivergent palladium-catalyzed process is unique in ynamide chemistry and allows for the elaboration of metallated-enamides that are useful building blocks for cross-coupling reactions or heterocyclic chemistry. DFT calculations fully support the experimental data and demonstrate the crucial roles of the <i>trans</i>-geometry of the [H-Pd(L)-Ge] complex, as well as of the steric requirements of the phosphine ligand. In addition, the prevalence of a hydro-palladation pathway over a metal-palladation of the pi system of the ynamide was demonstrated.

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

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

<p>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 <i>cis</i>- and <i>trans</i>-configured carboxylic acid building blocks from the C–H alkenylation products.</p>

Dual Nickel/Palladium-Catalyzed Reductive Cross-Coupling Reactions Between Two Phenol Derivatives

2020 ◽  
Author(s):  
Baojian Xiong ◽  
Yue Li ◽  
Yin Wei ◽  
Søren Kramer ◽  
Zhong Lian
Keyword(s):  
Functional Group ◽  
Low Cost ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Phenol Derivatives ◽  
Cross Coupling Reactions ◽  
Palladium Catalyzed ◽  
One Step ◽  
Aryl Tosylates ◽  
Low Sensitivity

Cross-coupling between substrates that can be easily derived from phenols is highly attractive due to the abundance and low cost of phenols. Here, we report a dual nickel/palladium-catalyzed reductive cross-coupling between aryl tosylates and aryl triflates; both substrates can be accessed in just one step from readily available phenols. The reaction has a broad functional group tolerance and substrate scope (>60 examples). Furthermore, it displays low sensitivity to steric effects demonstrated by the synthesis of a 2,2’disubstituted biaryl and a fully substituted aryl product. The widespread presence of phenols in natural products and pharmaceuticals allow for straightforward late-stage functionalization, illustrated with examples such as Ezetimibe and tyrosine. NMR spectroscopy and DFT calculations indicate that the nickel catalyst is responsible for activating the aryl triflate, while the palladium catalyst preferentially reacts with the aryl tosylate.

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