Selective 1,2-dihalogenation and oxy-1,1-dihalogenation of alkynes by N-halosuccinimides
摘要:
1,2-Dihalogenation and oxy-1,1-dihalogenation of alkynes by N-halosuccinimides can be selectively realized through using different reaction conditions. alpha,beta-Dihalo alkenes were obtained exclusively using THF as solvent without using any catalyst, while alpha,alpha-dihalo ketones were synthesized using a mixed solvent of THF and H2O in the presence of FeCl3 center dot 6H(2)O. Terminal aromatic alkynes are smoothly transformed into alpha,alpha-dihalo ketones on water without a catalyst. (C) 2011 Elsevier Ltd. All rights reserved.
A debrominationreaction to synthesize α‐mono‐ and α,α‐dibromomethylketones with high selectivity from α,α,α‐tribromomethylketones by the controlling of H2OHBr reductive conditions was developed.
Catalytic Enantioselective Addition of an Allyl Group to Ketones Containing a Tri-, a Di-, or a Monohalomethyl Moiety. Stereochemical Control Based on Distinctive Electronic and Steric Attributes of C–Cl, C–Br, and C–F Bonds
作者:Diana C. Fager、KyungA Lee、Amir H. Hoveyda
DOI:10.1021/jacs.9b08443
日期:2019.10.9
products enantioselectively but also in some cases there are hardly any instances of a catalytic enantioselectiveaddition of a carbon-based nucleophile (e.g., one enzyme-catalyzed aldol addition involving trichloromethyl ketones, and none with dichloromethyl, tribromomethyl, or dibromomethyl ketones). The approach is scalable and offers an expeditious route to the enantioselectivesynthesis of versatile
Modular and Chemoselective Strategy for Accessing (Distinct) α,α‐Dihaloketones from Weinreb Amides and Dihalomethyllithiums
作者:Saad Touqeer、Raffaele Senatore、Monika Malik、Ernst Urban、Vittorio Pace
DOI:10.1002/adsc.202001106
日期:2020.11.18
The selective transfer of diversely functionalized dihalomethyllithiums (LiCHBrCl, LiCHClI, LiCHBrI, LiCHCl2, LiCHBr2, LiCHFI) to Weinreb amides for preparing gem‐dihaloketones in one synthetic operation is reported. The capability of these amides as acylating agents and, the wide availability of dihalomethanes as pronucleophiles, enable a straightforward route to the title compounds under full chemocontrol
Selective 1,2-dihalogenation and oxy-1,1-dihalogenation of alkynes by N-halosuccinimides
作者:Jinhua Liu、Wenjuan Li、Chao Wang、Yao Li、Zhiping Li
DOI:10.1016/j.tetlet.2011.06.047
日期:2011.8
1,2-Dihalogenation and oxy-1,1-dihalogenation of alkynes by N-halosuccinimides can be selectively realized through using different reaction conditions. alpha,beta-Dihalo alkenes were obtained exclusively using THF as solvent without using any catalyst, while alpha,alpha-dihalo ketones were synthesized using a mixed solvent of THF and H2O in the presence of FeCl3 center dot 6H(2)O. Terminal aromatic alkynes are smoothly transformed into alpha,alpha-dihalo ketones on water without a catalyst. (C) 2011 Elsevier Ltd. All rights reserved.