Les vitesses et equilibres sont rapportes pour une serie de reaction d'arylmethylseeniures avec l'ion p-氯苯基二甲基硒。Les vitesses de reaction Experimentales entre les agent demethylation «durs» et les nucleophiles «mous» presentent des petites biass par rapport aux valeurs calculees, principalement mais pas toujours dans le sens prevu par le principe HSAB
New synthetic methods : sodium alkanechalcogenates as demethylating agents. Scope, limitation and new one-pot synthesis of diaryldiselenides.
作者:Michel Evers、Léon Christiaens
DOI:10.1016/s0040-4039(00)81412-4
日期:——
Sodium alkanechalcogenates (S, Se) cleave the alkylarylchalcogenides (O, S, Se). The versatility of such reagents is developed and applied to a newsynthesis of diaryldiselenides.
Metal‐Free Synthesis of Selenodihydronaphthalenes by Selenoxide‐Mediated Electrophilic Cyclization of Alkynes
作者:Shaoyu An、Zhong Zhang、Pingfan Li
DOI:10.1002/ejoc.202100423
日期:2021.6.7
A metal-free, one-pot selenium mediated electrophiliccyclization reaction of alkynes and triflic anhydride-activated selenoxides was realized, giving selenium containing dihydronaphthalene products, including selenium-substituted phenanthrene, dihydroquinoline, 2H-chromene, and coumarin.
FeCl<sub>3</sub>-Diorganyl Dichalcogenides Promoted Cyclization of 2-Alkynylanisoles to 3-Chalcogen Benzo[<i>b</i>]furans
作者:Rafaela M. Gay、Flávia Manarin、Caroline C. Schneider、Daniela A. Barancelli、Michael D. Costa、Gilson Zeni
DOI:10.1021/jo101126q
日期:2010.8.20
2-alkynylanisoles, via FeCl3/diorganyl dichalcogenides intramolecular cyclization, has been developed. Aryl and alkylgroups directly bonded to the chalcogen atom were used as cycling agents. The results revealed that the reaction significantly depends on the electronic effects of substituents in the aromatic ring bonded to the selenium atom of the diselenide species. We observed that the pathway of reaction was
通过FeCl 3从容易获得的2-炔基苯甲醚中合成3-硫属元素苯并[ b ]呋喃/ diorganyl dichalcogenides分子内环化已得到开发。直接结合到硫属元素原子上的芳基和烷基用作循环剂。结果表明,该反应显着取决于与二硒化物物种的硒原子键合的芳环中取代基的电子效应。我们观察到反应途径对苯甲醚芳环中取代基的性质不敏感,因为给电子基团和吸电子基团均以相似的产率传递产物。此外,将得到的杂环被容易地通过使用与硫属/锂交换反应转化成更复杂的产品Ñ-BuLi,然后用醛截留锂中间体,以良好的产率提供所需的仲醇。
Syntheses of Alkali Selenolates from Diorganic Diselenides and Alkali Metal Hydrides: Scope and Limitations
作者:Alain Krief、Mahmoud Trabelsi、Willy Dumont
DOI:10.1055/s-1992-26266
日期:——
Sodium and potassium alkane[arene]selenolates have been efficiently prepared from the corresponding diselenides using sodium or potassium hydrides in dimethylformamide or tetrahydrofuran. The reaction cannot be extended for the production of their lithium analogues nor for sodium and potassium phenylmethaneselenolates.
Selenium and tellurium derivatives of π-cyclopentadienylnickel tri-n-butylphosphine
作者:Masao Sato、Tadao Yoshida
DOI:10.1016/s0022-328x(00)93520-4
日期:1973.4
formula π-C5H5Ni[P(n-C4H9)3]SeC6H4X (I) (where X is H, p-CH3O, p-CH3, p-Cl, m-Cl, mCF3, and p-CH3CO) and π-C5H5Ni-[P(n-C4H9)3]TeC6H4X (II) (where X is H, p-CH3O, p-CH3, p-Cl, and m-CF3) have been prepared and their NMR spectra recorded. Good correlations exist between the 1H chemical shifts of the π-C5H5 group and the Hammett σ-constants of X for both (I) and (II). The Hammett ϱ values were found to be