Synthesis of Diverse C2-Glyco-Acyl Azides and -Ureas by Palladium-Catalyzed Carbonylation Coupling of 2-Iodoglycals

2020 ◽  
Vol 2020 (25) ◽  
pp. 3847-3855
Author(s):  
Antônio Augusto Soares-Paulino ◽  
Hélio A. Stefani
Synlett ◽  
2020 ◽  
Vol 31 (11) ◽  
pp. 1040-1049
Author(s):  
Xuefeng Li ◽  
Zhenhua Zhang ◽  
Jiyao Feng ◽  
Zhen Zhang

Isocyanates are widely applied in the fields of materials science, drug discovery and chemical industry processes. Palladium-catalyzed carbonylation of azides with carbon monoxide (CO) is reported as a powerful method for simple and efficient access to isocyanates, which are important precursors for preparing structurally meaningful urea, carbamate and amidine derivatives. In this account, we provide an overview on the synthesis of isocyanates and their subsequent reactions to obtain diverse nucleophilic addition products. In addition, with particular emphasis on our mechanistic studies of the Pd-catalyzed carbonylation process, we outline the identification of the actual catalytic species, the possible intermediates and some key factors in the catalytic cycle.1 Introduction2 Palladium-Catalyzed Reaction of Azides with CO and Subsequent Nucleophilic Additions3 Mechanistic Studies on the Palladium-Catalyzed Reaction of Azides with CO3.1 Studies on the Actual Catalytic Species and the Key Intermediates in the Activation and Carbonylation of Acyl Azides3.2 Study of the Sulfonylurea Product Self-Catalyzed Carbonylation of Sulfonyl Azides3.3 Study of the Actual Catalytic Pattern of the Pd/C Catalyst4 Conclusion


2020 ◽  
Vol 7 (19) ◽  
pp. 2938-2943
Author(s):  
Yeojin Kim ◽  
Kwang Ho Song ◽  
Sunwoo Lee

Aryl sulfonyl hydrazide reacted with aryl iodide in the presence of CO to give the corresponding S-aryl thioesters.


2020 ◽  
Vol 7 (6) ◽  
pp. 885-889 ◽  
Author(s):  
Xinxin Qi ◽  
Zhi-Peng Bao ◽  
Xiao-Feng Wu

A palladium-catalyzed carbonylative transformation of aryl iodides and sulfonyl chlorides to thioesters has been studied.


Synlett ◽  
1991 ◽  
Vol 1991 (09) ◽  
pp. 697-698 ◽  
Author(s):  
Tadakatsu Mandai ◽  
Hiroaki Kunitomi ◽  
Kiyoto Higashi ◽  
Mikio Kawada ◽  
Jiro Tsuji

2020 ◽  
Author(s):  
Kiron Kumar Ghosh ◽  
Alexander Uttry ◽  
Francesca Ghiringhelli ◽  
Arup Mondal ◽  
Manuel van Gemmeren

We report the ligand enabled C(sp3)–H activation/olefination of free carboxylic acids in the γ-position. Through an intramolecular Michael-addition, δ-lactones are obtained as products. Two distinct ligand classes are identified that enable the challenging palladium-catalyzed activation of free carboxylic acids in the γ-position. The developed protocol features a wide range of acid substrates and olefin reaction partners and is shown to be applicable on a preparatively useful scale. Insights into the underlying reaction mechanism obtained through kinetic studies are reported.<br>


2020 ◽  
Author(s):  
Aleksandra Balliu ◽  
Aaltje Roelofje Femmigje Strijker ◽  
Michael Oschmann ◽  
Monireh Pourghasemi Lati ◽  
Oscar Verho

<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>


Sign in / Sign up

Export Citation Format

Share Document