General Synthesis of Alkenyl Sulfides by Palladium-Catalyzed Thioetherification of Alkenyl Halides and Tosylates
作者:Noelia Velasco、Cintia Virumbrales、Roberto Sanz、Samuel Suárez-Pantiga、Manuel A. Fernández-Rodríguez
DOI:10.1021/acs.orglett.8b00854
日期:2018.5.18
ligand is reported. These reactions occur under low catalyst loading and in high yields and display widescope, including the coupling of bulky thiols and trisubstituted bromoolefins, and functional group tolerance. In addition, the thioetherification of less reactive chloroalkenes and, for the first time, alkenyl tosylates was accomplished using a catalyst generated from CyPFtBu alkylbisphosphine ligand
据报道,链烯基溴化物与硫醇的交联反应是由廉价dppf配体衍生的钯配合物催化的。这些反应在低催化剂负载和高收率下发生,并显示出较宽的范围,包括大体积硫醇和三取代溴代烯烃的偶联以及官能团的耐受性。另外,使用由CyPF t Bu烷基双膦配体产生的催化剂实现了反应性较低的氯代烯烃的硫醚化以及首次甲苯基甲苯磺酸酯的硫醚化。
On some indenoisoxazole derivatives
作者:G. Bianchi、R. Gandolfi、P. Grünanger、A. Perotti
DOI:10.1039/j39670001598
日期:——
From the cycloaddition of acetonitrile N-oxide with indene two isomeric methyldihydroindenoisoxazoles have been isolated. Elucidation of their structures by bromination and 1H n.m.r. spectroscopy, and related reactions on analogous compounds are described.
从乙腈N-氧化物与茚的环加成中,已经分离出两种异构体甲基二氢茚并异恶唑。描述了通过溴化和1 H nmr光谱对其结构的阐明,以及对类似化合物的相关反应。
Lewis Base/Brønsted Acid Co‐catalyzed Enantioselective Sulfenylation/Semipinacol Rearrangement of Di‐ and Trisubstituted Allylic Alcohols
accomplished with a chiral Lewis base and a chiral Brønsted acid as cocatalysts, generating various β-arylthio ketones bearing an all-carbon quaternary center in moderate to excellent yields and excellent enantioselectivities. These chiral arylthio ketone products are common intermediates with many applications, for example, in the design of new chiral catalysts/ligands and the totalsynthesis of natural products
The Selective Cross-Coupling of Secondary Alkyl Zinc Reagents to Five-Membered-Ring Heterocycles Using Pd-PEPPSI-IHept<sup>Cl</sup>
作者:Bruce Atwater、Nalin Chandrasoma、David Mitchell、Michael J. Rodriguez、Matthew Pompeo、Robert D. J. Froese、Michael G. Organ
DOI:10.1002/anie.201503941
日期:2015.8.10
leads to β‐hydride elimination. Whereas catalysts have been reported that provide decent selectivity for the expected (non‐rearranged) cross‐coupled product with aryl or heteroaryl oxidative‐addition partners, none have shown reliable selectivity with five‐membered‐ring heterocycles. In this report, a new, rationally designed catalyst, Pd‐PEPPSI‐IHeptCl, is demonstrated to be effective in selective
Competitive, substrate-dependent reductive debromination/dehydrobromination of 1,2-dibromides with triethylamine
作者:Kristen M. McGraw、Greggory T. Kent、Joseph R. Gonzalez、Ihsan Erden、Weiming Wu
DOI:10.1016/j.tetlet.2017.04.024
日期:2017.5
various 1,2-dibromides with NEt3 under various conditions (THF and DMF, respectively) at different temperatures was investigated. Our results from these reactions show that substrate dependent dehydrobrominations compete with reductive debrominations. A comprehensive discussion of these competitive pathways is offered.