当用紫外光照射时,带有光响应芳烃配体的定制钌夹心配合物可以有效促进叠氮硫炔环加成(RuAtAC)。该反应可以在含有生物组分的水性混合物中以生物正交方式进行。该策略还可以应用于生物聚合物的选择性修饰,例如 DNA 或肽。重要的是,这种钌基技术和标准铜催化叠氮化物-炔环加成(CuAAC)被证明是兼容且相互正交的。
An efficient preparation for arylethynyl sulfides 1 and bis(arylethynyl) sulfides 2 has been accomplished through a one-pot, three-step strategy that starts from arylethanonyl sulfides and bis(arylethanonyl) sulfides, respectively, without the use of various terminal arylacetylenes as substrates. When lithium hexamethyldisilazane (LHMDS), ClP(O)(OEt)2, and LHMDS were sequentially added to a tetrahydrofuran
Alkynyl Thioethers in Gold-Catalyzed Annulations To Form Oxazoles
作者:Raju Jannapu Reddy、Matthew P. Ball-Jones、Paul W. Davies
DOI:10.1002/anie.201706850
日期:2017.10.16
regioselective, and convergent access to densely functionalized oxazoles is realized in a functional-group tolerant manner using alkynylthioethers. Sulfur-terminated alkynes provide access to reactivity previously requiring strong donor-substituted alkynes such as ynamides. Sulfur does not act in an analogous donor fashion in this gold-catalyzed reaction, thus leading to complementary regioselective outcomes
arylalkenes and aryl bromides with hydrosilanes by cooperative palladium/copper catalysis was developed, thus resulting in the highly regioselective formation of various 1,1‐diarylalkanes, including a biologically active molecule. Under the applied reaction conditions, high levels of functional‐group tolerance were observed, and the reductive cross‐coupling of internal alkynes with aryl bromides afforded
a highly modular, clean, and scalable access to a broad variety of alkynyl sulfides in good‐to‐excellent yields. The utility of this protocol was showcased by the preparation of alkynyl sulfides, which are particularly difficult to obtain or simply unavailable through the existing methodologies. In addition, the synthetic method was extended to the preparation of alkynyl selenides.
A metal-free regio- and stereoselective method is achieved for the preparation of (E)-configured α-halo enamides, vinyl thioethers, and vinyl ethers using aqueous HX (X = F, Cl, Br, I), which features high functional group compatibility and regio- and stereoselectivity, mild conditions, high efficiency, and rapid transformation. Additionally, the isomers could be yielded readily from the (E)-configured