Single-Electron-Transfer Strategy for Reductive Radical Cyclization: Fe(CO)<sub>5</sub> and Phenanthroline System
作者:Joon Young Hwang、Jong Hwa Baek、Tae Il Shin、Jung Ha Shin、Jae Won Oh、Kwang Pyo Kim、Youngmin You、Eun Joo Kang
DOI:10.1021/acs.orglett.6b02375
日期:2016.10.7
electron-transfer strategy using low-valent iron pentacarbonyl [Fe(CO)5] to generate radical species from alkyl iodides was achieved. A range of pyrrolidines, tetrahydrofurans, and carbocycles were synthesized via 5-exo cyclization reactions of alkyl radical intermediates generated by electron transfer from a system involving Fe(CO)5, 1,10-phenanthroline, and diisopropylamine. Moreover, tandem addition
Ester Formation via Nickel-Catalyzed Reductive Coupling of Alkyl Halides with Chloroformates
作者:Min Zheng、Weichao Xue、Teng Xue、Hegui Gong
DOI:10.1021/acs.orglett.6b03158
日期:2016.12.2
The synthesis of alkyl esters from readily available alkyl halides and chloroformates was achieved for the first time using a mild Ni-catalyzed reductive coupling protocol. Unactivated primary and secondary alkyl iodides as well as glycosyl, benzyl, and aminomethyl halides were successfully employed to yield products in moderate to excellent yields with high functional group tolerance.
Mapping Ambiphile Reactivity Trends in the
<i>Anti</i>
‐(Hetero)annulation of Non‐Conjugated Alkenes via Pd
<sup>II</sup>
/Pd
<sup>IV</sup>
Catalysis
作者:Hui‐Qi Ni、Phillippa Cooper、Shouliang Yang、Fen Wang、Neal Sach、Pranali G. Bedekar、Joyann S. Donaldson、Michelle Tran‐Dubé、Indrawan J. McAlpine、Keary M. Engle
DOI:10.1002/anie.202114346
日期:2022.3.21
from non-conjugated alkenyl amides and ambiphilic organohalides is described. Under PdII/PdIV catalysis, this [n+2] annulation proceeds in an anti-selective fashion and tolerates a wide array of ambiphiles, which are systematically benchmarked with respect to nucleophile identity, electrophile identity, and product ring-size. Otherwise unreactive ambiphilic ortho-haloacetophenones can be activated
描述了从非共轭烯基酰胺和两亲性有机卤化物获得 5、6 和 7 元碳环和杂环的方法。在 Pd II /Pd IV催化下,这种 [ n +2] 环化以反选择性方式进行,并耐受多种双亲剂,这些双亲剂在亲核体特性、亲电子体特性和产物环大小方面进行了系统的基准测试。另外,非反应性两亲性邻卤代苯乙酮可以使用胺助催化剂来活化。
Ligand-Controlled Cobalt-Catalyzed Regio-, Enantio-, and Diastereoselective Oxyheterocyclic Alkene Hydroalkylation
developed as an efficient method for C(sp3)–C(sp3) coupling with broad substrate availability and high functional group compatibility. However, auxiliary groups, a conjugated group or a chelation-directing group, are commonly required to attain high regio- and enantioselectivities. Herein, we reported a ligand-controlled cobalt-hydride-catalyzed regio-, enantio-, and diastereoselective oxyheterocyclic
FeCl<sub>2</sub>
-mediated Nucleophilic Chlorination of Iodoalkanes Accelerated by Phenanthroline Ligand
作者:Joon Young Hwang、Jung Ha Shin、Eun Young Seong、Eun Joo Kang
DOI:10.1002/bkcs.11453
日期:2018.5
Alkyl halides have been considered not only important building blocks but also useful intermediates in synthetic methods of nucleophilic substitution, metal-halogen exchange, and cross-coupling reactions. As the practical synthesis of various alkyl halides, the halogen exchange is one of the fundamental and efficient reactions, which is mainly used for preparing alkyl bromides or iodides. Finkelstein-type reactions(1) have been well studied for the conversion of alkyl chlorides to the corresponding bromides or iodides and alkyl bromides to iodides, which reaction is an equilibrium shifted by taking advantage of the different solubility of the resulting sodium salt in acetone. However, the reverse processes, the replacement of iodide by bromide or chloride, or of bromide by chloride, were not simple.