of nitrogen‐centered radicals, generated through electrochemical oxidation, to alkenes followed by trapping of the cyclized radical intermediate with 2,2,6,6‐tetramethylpiperidine‐N‐oxyl radical (TEMPO). Difunctionalization of a variety of alkenes with easily available carbamates/amides and TEMPO affords aminooxygenation products in high yields and with excellent trans selectivity for cyclic systems
Intramolecular Aryne–Ene Reaction: Synthetic and Mechanistic Studies
作者:David A. Candito、Jane Panteleev、Mark Lautens
DOI:10.1021/ja205405n
日期:2011.9.14
chemistry of arynes is well developed, some challenges still remain. The ene reaction of arynes has not gained widespread use in synthesis as a result of poor yields and selectivity. A general, high yielding and selective intramolecular aryne-ene reaction is described providing various benzofused carbo- and heterocycles. Mechanistic data is presented, and a rationale for the resulting stereochemistry is
[2,3] Sigmatropic Rearrangement of Unstable Sulfur Ylides from Allyl Sulfonium Salts. Comparative Study of Electrochemical Reduction with the Base Method and Mechanism Elucidation by the MO Method
作者:Yuichi Okazaki、Fumio Ando、Jugo Koketsu
DOI:10.1246/bcsj.77.1687
日期:2004.9
reduction of sulfoniumsalts in acetonirile under the presence and absence of benzaldehyde were carried out and compared with the results of the base method. Under the presence of benzaldehyde, the electrochemical reduction gave epoxides as a result of a Corey-Chaykovsky reaction confirming ylide formation. The electrochemical reduction of sulfonium salt without benzaldehyde yields the same [2,3] sigmatropic
We describe an approach to N‐tosyl 1,3‐amino alcohols that consists of a diastereoselective aziridination reaction of acyclic allylic alcohols and an unprecedented regioselective hydrosilylation of α‐hydroxy aziridines. The products contain up to three contiguous stereocenters. Computational studies outline key aspects of the aziridination mechanism, which is different and more intricate than anticipated
A Convenient Method for the Transformation of Allylstannanes to Alcohols, Ethers, Esters, and Amines
作者:Takeshi Takeda、Tomoya Inoue、Tooru Fujiwara
DOI:10.1246/cl.1988.985
日期:1988.6.5
Allylstannanes were easily oxidized with copper(II) bromide in the presence of water, alcohols, and sodium acetate to give the corresponding allylic alcohols, ethers, and acetates, respectively. The allylic amines were also obtained by the successive treatments of allylstannanes with copper(II) bromide and amines.
在水、醇和乙酸钠的存在下,烯丙基锡烷很容易被溴化铜 (II) 氧化,分别得到相应的烯丙醇、醚和乙酸酯。烯丙基胺也是通过用溴化铜 (II) 和胺连续处理烯丙基锡烷而获得的。