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
Switchable Synthesis of α,α‐Dihalomethyl and α,α,α‐Trihalomethyl Ketones by Metal‐Free Decomposition of Enaminone C=C Double Bond
作者:Yunyun Liu、Jin Xiong、Li Wei、Jie‐Ping Wan
DOI:10.1002/adsc.201901234
日期:2020.2.21
(BPO) with mild heating, enabling the tunable synthesis of α,α‐dihalomethyl ketones and α,α,α‐trihalomethyl ketones under different reaction conditions. The formation of these divergent products involving featured C=C double bond cleavage requires no any metal reagent, and represents one more practical example on the synthesis of poly halogenated methyl ketones via the functionalization of carbon−carbon
An Easy Synthesis of 2-Haloacetylfurans and -Thiophenes
作者:Jacques Dubac、Antoine Gaset、Martine Maraval
DOI:10.1080/00397919108020784
日期:1991.1
Abstract The 2-chloro (or bromo)acetylfurans and-thiophenes were selectively synthesized with preservation of the heteroaromatic cycle from enoxysilane forms of 2-acetylfurane and-thiophene.
Solvent-Free Chemoselective Cyanation of α,α-Dibromoacetophenones Using Potassium Hexacyanoferrate(II) as an Eco-Friendly Cyanide Source
作者:Zhouxing Zhao、Zheng Li
DOI:10.1002/ejoc.201000848
日期:——
A chemoselective route for the synthesis of 2-aryl-3,3-di-bromoacrylonitriles by solvent-freecyanation of α,α-dibromoacetophenones by usingpotassiumhexacyanoferrate(II) as an eco-friendlycyanidesource is developed. The merits of this procedure include avoiding the use of a strong toxic cyanidesource, a catalyst, and volatile organic solvents and the high yields of the products.
开发了使用六氰基高铁酸钾 (II) 作为环保氰化物源,通过 α,α-二溴苯乙酮的无溶剂氰化合成 2-芳基-3,3-二溴丙烯腈的化学选择性路线。该程序的优点包括避免使用剧毒的氰化物源、催化剂和挥发性有机溶剂以及产品的高产率。
Kinetic Resolution of Electron-Deficient Bromohydrins via Copper(II)-Catalyzed C–C Bond Cleavage
作者:Kavita Choudhary、Rayhan G. Biswas、Abhijit Manna、Vinod K. Singh
DOI:10.1021/acs.joc.3c01368
日期:2023.8.18
ketone-derived bromohydrins (up to s = 211) with N-bromosuccinimide (NBS) in the presence of a chiral Cu(II)-Box catalyst via the C–C bond cleavage of the fast reacting enantiomer. A one-pot synthesis–KR approach of the same has also been realized with excellent enantioselectivities (up to 99% ee). Both protocols are found to be effective for a variety of substrates, leading to enantioenriched bromohydrins. The