3323-78-2Relevant academic research and scientific papers
Modular and Chemoselective Strategy for Accessing (Distinct) α,α-Dihaloketones from Weinreb Amides and Dihalomethyllithiums
Malik, Monika,Pace, Vittorio,Senatore, Raffaele,Touqeer, Saad,Urban, Ernst
supporting information, p. 5056 - 5061 (2020/10/21)
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. No racemization phenomena were evidenced in the case of optically active materials. Additionally, tolerance to sensitive functional groups (esters, amides, halogens, olefins etc.) was uniformly noticed, thus making this conceptually intuitive strategy flexible and tunable by the operator. (Figure presented.).
Water-controlled selective preparation of α-mono or α,α′-dihalo ketones: Via catalytic cascade reaction of unactivated alkynes with 1,3-dihalo-5,5-dimethylhydantoin
Wu, Chao,Xin, Xiu,Fu, Zhi-Min,Xie, Long-Yong,Liu, Kai-Jian,Wang, Zheng,Li, Wenyi,Yuan, Zhi-Hui,He, Wei-Min
, p. 1983 - 1989 (2017/06/09)
The control of a reaction that can produce multiple products from the same starting material is a highly attractive and challenging concept in organic synthesis. An efficient protocol for the selective synthesis of α-mono or α,α′-dihalo ketones via a water-controlled three-component thiourea-catalyzed cascade reaction of unactivated alkynes, 1,3-dihalo-5,5-dimethylhydantoin and water has been developed. α-Monohaloketones were obtained in aqueous acetone at 45 °C; conversely, α,α′-dihalo ketones were formed with pure water as the sole solvent at room temperature.
