Rhodium Dinaphthocyclooctatetraene Complexes: Synthesis, Characterization and Catalytic Activity in [5+2] Cycloadditions
作者:Paul A. Wender、Adam B. Lesser、Lauren E. Sirois
DOI:10.1002/anie.201108270
日期:2012.3.12
Rh COT in the act: A Ni0‐catalyzed [2+2+2+2] cycloaddition provides a high‐yielding, scalable synthesis of the ligand dinaphtho[a,e]cyclooctatetraene (dnCOT). dnCOT complexation with RhI gives [Rh(dnCOT)(MeCN)2]SbF6 (see scheme), an excellent catalyst for [5+2] cycloadditions of vinylcyclopropanes and π‐systems with impressive functional group compatibility.
3-Silaazetidine: An Unexplored yet Versatile Organosilane Species for Ring Expansion toward Silaazacycles
作者:Wanshu Wang、Song Zhou、Linjie Li、Yuanhang He、Xue Dong、Lu Gao、Qiantao Wang、Zhenlei Song
DOI:10.1021/jacs.1c04667
日期:2021.7.28
Small-ring silacycles are important organosilane species in main-group chemistry and have found numerous applications in organic synthesis. 3-Silaazetidine, a unique small silacycle bearing silicon and nitrogen atoms, has not been adequately explored due to the lack of a general synthetic scheme and its sensitivity to air. Here, we describe that 3-silaazetidine can be easily prepared in situ from diverse
An efficient and facile method for the preparation of alkynamides through Et3N-catalyzed alumination of alkyl- or aryl-substituted terminal alkynes with AlMe3 and sequential nucleophilic addition of in situ generated alkynylaluminums to isocyanates is described. This method has the merits of using readily available isocyanates and monosubstituted alkynes, easy access to organoaluminums, short reaction
描述了一种通过 Et 3 N 催化用 AlMe 3对烷基或芳基取代的末端炔烃进行铝化以及将原位生成的炔基铝连续亲核加成到异氰酸酯上来制备炔酰胺的有效且简便的方法。该方法具有使用易得的异氰酸酯和单取代炔烃、有机铝易获得、反应时间短、效率高等优点。所需炔酰胺的克级合成及其在 α-亚甲基-β-内酰胺形成中的应用证明了该方法的合成效用。
Metal-Free Transfer Hydroiodination of C–C Multiple Bonds
作者:Weiqiang Chen、Johannes C. L. Walker、Martin Oestreich
DOI:10.1021/jacs.8b12318
日期:2019.1.16
The design and a gram-scalesynthesis of a bench-stable cyclohexa-1,4-diene-based surrogate of gaseous hydrogen iodide are described. By initiation with a moderately strong Brønsted acid, hydrogen iodide is transferred from the surrogate onto C-C multiple bonds such as alkynes and allenes without the involvement of free hydrogen iodide. The surrogate fragments into toluene and ethylene, easy-to-remove
描述了基于环己-1,4-二烯的气态碘化氢替代品的设计和克级合成。通过用中等强度的布朗斯台德酸引发,碘化氢从替代物转移到 CC 多重键上,例如炔烃和丙二烯,而没有游离碘化氢的参与。代用品碎片化为甲苯和乙烯,易挥发废物。这种氢碘化反应避免了对碘化氢或氢碘酸的不稳定处理。通过这种方式,可以以立体控制的方式访问范围广泛的以前未知或难以制备的乙烯基碘。
Stereodivergent Synthesis of Tertiary Fluoride-Tethered Allenes via Copper and Palladium Dual Catalysis
作者:Shao-Qian Yang、Yi-Fan Wang、Wei-Cheng Zhao、Guo-Qiang Lin、Zhi-Tao He
DOI:10.1021/jacs.1c03157
日期:2021.5.19
protocol for the unprecedented stereodivergentsynthesis of tertiary fluoride-tethered allenes bearing a stereogenic center and stereogenic axis via Cu/Pdsynergisticcatalysis. A broad scope of conjugated enynes are coupled with various α-fluoroesters in high yields with high diastereoselectivities and generally >99% ee. In addition, the four stereoisomers of the allene products ensure precise access