Enantioselective Copper-Catalyzed Oxy-Alkynylation of Diazo Compounds
作者:Durga Prasad Hari、Jerome Waser
DOI:10.1021/jacs.7b04756
日期:2017.6.28
Enantioselective catalytic methods allowing the addition of both a nucleophile and an electrophile onto diazocompounds give a fast access into important building blocks. Herein, we report the highly enantioselective oxyalkynylation of diazocompounds using ethynylbenziodoxol-(on)e reagents and a simple copper bisoxazoline catalyst. The obtained α-benzoyloxy propargylic esters are useful building blocks
A novel regio‐ and diastereoselective iron‐catalyzed intermolecular oxyazidation of enamidesusing various azidobenziodoxolone (ABX) derivatives is presented. A variety of α‐N3 amino derivatives and of α‐N3 piperidines were synthesized in good yields and under mild reaction conditions. The reaction involves a radical process using cheap FeCl2 as the initiator.
Copper-Catalyzed Oxy-Alkynylation of Diazo Compounds with Hypervalent Iodine Reagents
作者:Durga Prasad Hari、Jerome Waser
DOI:10.1021/jacs.6b00278
日期:2016.2.24
Alkynes have found widespread applications in synthetic chemistry, biology, and materials sciences. In recent years, methods based on electrophilic alkynylation with hypervalent iodine reagents have made acetylene synthesis more flexible and efficient, but they lead to the formation of one equivalent of an iodoarene as side-product. Herein, a more efficient strategy involving a copper-catalyzed oxy-alkynylation
Ethynyl Benziodoxolones for the Direct Alkynylation of Heterocycles: Structural Requirement, Improved Procedure for Pyrroles, and Insights into the Mechanism
作者:Jonathan P. Brand、Clara Chevalley、Rosario Scopelliti、Jérôme Waser
DOI:10.1002/chem.201200200
日期:2012.4.27
accelerating effect of a methyl substituent in both the 3‐ and 6‐position of triisopropylsilylethynyl‐1,2‐benziodoxol‐3(1H)‐one (TIPS‐EBX) on the reaction rate was observed. Competitive experiments between substrates of different nucleophilicity, deuterium labeling experiments, as well as the regioselectivity observed are all in agreement with electrophilic aromatic substitution. Gold(III) 2‐pyridinecarboxylate
Synthesis, Characterization of Spirocyclic λ
<sup>3</sup>
‐Iodanes and Their Application to Prepare 4,1‐Benzoxazepine‐2,5‐diones and 1,3‐Diynes
作者:Xu Sun、Xiao‐Qiang Guo、Lian‐Mei Chen、Tai‐Ran Kang
DOI:10.1002/chem.202005124
日期:2021.3
cycloaddition of aza‐oxyallylic cations with ethynylbenziodoxolones for synthesis of new λ3‐iodanes containing spirocyclic 4‐oxazolidinone has been developed. This cyclic λ3‐iodanes display stability in air and excellent solubility in organic solvent. Using them as substrate, both the 4,1‐benzoxazepine‐2,5‐diones and symmetrical 1,3‐diynes derivatives were afforded in high yield under copper(I)‐catalyzed