Synthesis of N- and B-Substituted Derivatives of closo-Amino-undecahydro-dodecaborate(1-) Anion

1997 ◽  
Vol 62 (8) ◽  
pp. 1185-1204 ◽  
Author(s):  
Bohumír Grüner ◽  
Bernard Bonnetot ◽  
Henri Mongeot
Keyword(s):  
Dimethyl Sulfate ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
The Novel ◽  
H Nmr ◽  
Palmitoyl Chloride ◽  
Fab Mass Spectrometry ◽  
Cross Coupling Reaction ◽  
Selective Substitution ◽  
Derivatives Of

The synthesis of nitrogen and boron substituted derivatives of the 1-amino-closo-dodecaborate anion(1-) 1 is reported. Reasonable yields of the [R2NH-B12H11]- derivatives (R = C6H5CH2, 2-C10H7CH2, n-C16H33, n-C12H25) were obtained via conventional alkylation of 1 in aqueous propan-2-ol, starting from bulky primary alkylhalides. These [R2NH-B12H11]- derivatives were subsequently methylated by dimethyl sulfate under similar conditions. Reaction of 1 with palmitoyl chloride gave under anhydrous conditions the corresponding N-acyl derivative. Reaction of 1 with hydroxymethyl-18-crown-6 tosylate in THF in the presence of NaH led to the novel [(18-crown-6-CH2)2NH-B12H11]- anion, the Cs+ salt of which exhibits unusual solubility properties. A direct cyclization reaction of pentaethylene glycol ditosylate with 1 gave under similar conditions [(15-azacrown)-5-B12H11]-, the first known closo-borate anion with an attached aza-crown ring. These species exhibit potentially interesting complexation efficiency and solubility properties. Selective substitution of the boron cage by a bulky naphthyl substituent was achieved by palladium-mediated cross-coupling reaction between 1 and 1-BrMgC10H7. All derivatives were characterized by high-field 11B, 1H NMR and negative FAB mass spectrometry methods.

scholarly journals Some mechanistic aspects regarding the Suzuki–Miyaura reaction between selected ortho-substituted phenylboronic acids and 3,4,5-tribromo-2,6-dimethylpyridine

2018 ◽  
Vol 14 ◽  
pp. 2384-2393
Author(s):  
Piotr Pomarański ◽  
Piotr Roszkowski ◽  
Jan K Maurin ◽  
Armand Budzianowski ◽  
Zbigniew Czarnocki
Keyword(s):  
Coupling Reaction ◽  
Cross Coupling ◽  
X Ray ◽  
H Nmr ◽  
Important Group ◽  
Cross Coupling Reaction ◽  
Efficient Access ◽  
Phenylboronic Acids ◽  
Derivatives Of ◽  
Single Bonds

Background: Atropisomers are very interesting stereoisomers having axial chirality resulting from restricted rotation around single bonds and are found in various classes of compounds. ortho-Substituted arylpyridines are an important group of them. A regio- and atropselective Suzuki–Miyaura cross-coupling reaction on 3,4,5-tribromo-2,6-dimethylpyridine was studied. Results: Reactions with various amounts of ortho-substituted phenylboronic acids with 3,4,5-tribromo-2,6-dimethylpyridine gave a series of mono- di- and triarylpyridine derivatives which allowed to draw conclusions about the order of substitution. Also, the observed selectivity in the case of ortho-methoxyphenylboronic acid suggested an additional metal O-chelation effect in the transition state, apparently not present in the ortho-chloro analogues. The rotational barrier in selected atropisomers was determined on the basis of HT NMR and thermal epimerisation experiments. The structure of most presented atropisomeric derivatives of 2,6-dimethylpyridine was confirmed by single-crystal X-ray analysis. Racemic chiral, differently substituted atropisomers were also examined by 1H NMR spectroscopy in the presence of a chiral solvating agent. Conclusion: This regio- and atropselectivity may be generally applicable to other arylpyridine systems. A regio- and atropselective Suzuki–Miyaura cross-coupling process has been observed, giving an efficient access to a class of atropisomeric compounds. An opposite selectivity using a differently ortho-substituted phenylbornic acid was observed.

scholarly journals Synthesis of 4-Alkyl-4H-1,2,4-triazole Derivatives by Suzuki Cross-coupling Reactions and Their Luminescence Properties

Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 652 ◽  
Author(s):  
Monika Olesiejuk ◽  
Agnieszka Kudelko ◽  
Marcin Swiatkowski ◽  
Rafal Kruszynski
Keyword(s):  
Ionic Liquids ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Boronic Acids ◽  
Luminescence Properties ◽  
Coupling Reactions ◽  
Triazole Derivatives ◽  
Cross Coupling Reactions ◽  
Cross Coupling Reaction ◽  
Derivatives Of

New derivatives of 4-alkyl-3,5-diaryl-4H-1,2,4-triazole were synthesized utilizing the Suzuki cross-coupling reaction. The presented methodology comprises of the preparation of bromine-containing 4-alkyl-4H-1,2,4-triazoles and their coupling with different commercially available boronic acids in the presence of ionic liquids or in conventional solvents. The obtained compounds were tested for their luminescence properties.

A Novel Reductive Cross-coupling Reaction of 2-nitrobenzoic Hydrazides and Aldehydes or Ketones Promoted by the Low-valence Titanium Reagent: An Access to 2,3,4,5-tetrahydro-1H-1,3,4-benzotriazepine-5-one Derivatives

2005 ◽  
Vol 2005 (9) ◽  
pp. 553-555 ◽  
Author(s):  
Daqing Shi ◽  
Chunling Shi ◽  
Liangce Rong ◽  
Juxian Wang ◽  
Qiya Zhuang ◽  
...  
Keyword(s):  
Elemental Analysis ◽  
Nmr Spectra ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Reductive Coupling ◽  
Facile Synthesis ◽  
H Nmr ◽  
Cross Coupling Reaction

A short and facile synthesis of a series of 2,3,4,5-tetrahydro-1H-1,3,4-benzotriazepine-5-one derivatives was accomplished in good yields via the intermolecular reductive coupling reaction of 2-nitrobenzoic hydrazides and aldehydes or ketones promoted by the low-valence titanium reagent (TiCl4/Zn system). Structures were established on the basis of elemental analysis, IR and 1H NMR spectra.

Palladium-Catalyzed Regioselective Heck–Suzuki–Miyaura Cascade Cyclization for the Synthesis of Trisubstituted Arylideneisoquinolinones

Synlett ◽  
2019 ◽  
Vol 30 (09) ◽  
pp. 1073-1076 ◽  
Author(s):  
M. Asgari ◽  
R. Mirzazadeh ◽  
B. Larijani ◽  
P. Rashidi Ranjbar ◽  
R. Rahimi ◽  
...  
Keyword(s):  
Coupling Reaction ◽  
Cross Coupling ◽  
Cascade Cyclization ◽  
Cross Coupling Reaction ◽  
Palladium Catalyzed ◽  
Derivatives Of

An Ugi four-component reaction was used to construct propargylamide starting materials for a subsequent domino Heck–Suzuki–Miyaura cross-coupling reaction to give derivatives of 4-benzylidene-1-oxo-3,4-dihydro-1H-isoquinoline.

scholarly journals Synthesis and Biological Evaluation of Novel 2-Substituted ­Analogues of (–)-Pentenomycin I

Synlett ◽  
2020 ◽  
Vol 31 (05) ◽  
pp. 475-481
Author(s):  
Stavroula A. Zisopoulou ◽  
Spyridon Bousis ◽  
Jörg Haupenthal ◽  
Jennifer Herrmann ◽  
Rolf Müller ◽  
...  
Keyword(s):  
Natural Product ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Eukaryotic Cell ◽  
Biological Evaluation ◽  
Gram Positive Bacteria ◽  
Cross Coupling Reaction ◽  
Palladium Catalyzed ◽  
Synthesis And Biological Evaluation ◽  
Derivatives Of

A library of novel 2-substituted derivatives of the antibiotic natural product pentenomycin I is presented. The new collection of analogues is divided in two main classes, 2-alkynyl- and 2-aryl- derivatives, which are accessed by the appropriate type of palladium-catalyzed cross-coupling reaction of the 2-iodo-protected pentenomycin I with suitable nucleophiles. The new derivatives were tested for their activity against certain types of bacteria and one of them, compound 8h, was found to exhibit significant inhibitory activity against several Gram-positive bacteria but also displayed cytotoxic activity against eukaryotic cell lines.

scholarly journals Synthesis and antifungal properties of papulacandin derivatives

2012 ◽  
Vol 8 ◽  
pp. 732-737 ◽  
Author(s):  
Marjolein van der Kaaden ◽  
Eefjan Breukink ◽  
Roland J Pieters
Keyword(s):  
Biological Activity ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Side Chain ◽  
Aryl Iodide ◽  
Glucan Synthase ◽  
Cross Coupling Reaction ◽  
Acyl Side Chain ◽  
Palladium Catalyzed ◽  
Derivatives Of

Derivatives of an antifungal agent that targets the β-(1,3)-D-glucan synthase, papulacandin D, were synthesized and tested for activity. The papulacandin D structure contains a challenging benzannulated spiroketal unit, which is introduced in a palladium-catalyzed cross-coupling reaction of a glycal silanolate and an aryl iodide followed by an oxidative spiroketalization. Four different variants were made, differing in the nature of the acyl side chain with respect to the length, and in the number and stereochemistry of the double bonds. Moderate biological activity was observed for the derivatives with a side chain based on palmitic acid and linoleic acid.

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