Sonogashira Cross-Coupling in the Synthesis of Acyclic Nucleoside Phosphonates: Preparation of 6-[(Phosphonomethoxy)alkynyl]- and 6-[(Phosphonomethoxy)alkyl]pyrimidines

2005 ◽  
Vol 70 (2) ◽  
pp. 247-258 ◽  
Author(s):  
Dana Hocková ◽  
Milena Masojídková ◽  
Antonín Holý

Several 6-[(phosphonomethoxy)alkyl]pyrimidines and 6-[(phosphonomethoxy)alkynyl]pyrimidines were prepared as saturated and unsaturated carba-analogues of antivirally active 2,4-diamino-6-[2-(phosphonomethoxy)ethoxy]pyrimidine. As the key step of their synthesis the Sonogashira cross-coupling reaction was successfully applied. The replacement of the C-O moiety by the C-C bond resulted in the loss of biological activity.

Tetrahedron ◽  
2011 ◽  
Vol 67 (38) ◽  
pp. 7379-7385 ◽  
Author(s):  
Petra Břehová ◽  
Michal Česnek ◽  
Martin Dračínský ◽  
Antonín Holý ◽  
Zlatko Janeba

2012 ◽  
Vol 8 ◽  
pp. 732-737 ◽  
Author(s):  
Marjolein van der Kaaden ◽  
Eefjan Breukink ◽  
Roland J Pieters

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.


2020 ◽  
Author(s):  
Evgeny Tretyakov ◽  
Svetlana Zhivetyeva ◽  
Pavel Petunin ◽  
Dmitry Gorbunov ◽  
Nina Gritsan ◽  
...  

<p>Verdazyl-nitroxide diradicals were synthesized using the palladium-catalyzed cross-coupling reaction of the corresponding iodoverdazyls with a nitronyl nitroxide-2-ide gold(I) complex with high yields (up to 82%). The synthesized diradicals were found to be highly thermally stable and have a singlet (D<i>E</i><sub>ST</sub> » -64 cm<sup>–1</sup>) or triplet ground state (D<i>E</i><sub>ST</sub> ³ 25 and 100 cm<sup>–1</sup>), depending on which canonical hydrocarbon diradical type they belong to. Upon crystallization, triplet diradicals form unique one-dimensional (1D) spin <i>S</i> = 1 chains of organic diradicals with intrachain ferromagnetic coupling of <i>J</i>′/<i>k</i><sub>B</sub> from 3 to 6 K.</p>


2020 ◽  
Author(s):  
Chet Tyrol ◽  
Nang Yone ◽  
Connor Gallin ◽  
Jeffery Byers

By using an iron-based catalyst, access to enantioenriched 1,1-diarylakanes was enabled through an enantioselective Suzuki-Miyaura crosscoupling reaction. The combination of a chiral cyanobis(oxazoline) ligand framework and 1,3,5-trimethoxybenzene additive were essential to afford high yields and enantioselectivities in cross-coupling reactions between unactivated aryl boronic esters and a variety of benzylic chlorides, including challenging ortho-substituted benzylic chloride substrates. Mechanistic investigations implicate a stereoconvergent pathway involving carbon-centered radical intermediates.


Author(s):  
Tiantian Chen ◽  
Yang Yang ◽  
Liyu Xie ◽  
Haijian Yang ◽  
Guangbin Dong ◽  
...  

<p>We report a Ni(0)-catalyzed cross coupling reaction between simple ketones and 1,3-dienes. A variety of a-allylic alkylation products were formed in an 1,2-addition manner with excellent regioselectivity. Water was found to significantly accelerate this transformation. A HO-Ni-H species generated from oxidative addition of Ni(0) to H<sub>2</sub>O is proposed to play a “dual role” in activating both the ketone and the diene substrate.</p>


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