81288-75-7Relevant academic research and scientific papers
A Unified and Desymmetric Approach to Chiral Tertiary Alkyl Halides
Huang, Zhongxing,Low, Kam-Hung,Zhang, Suihan,Zheng, Yin,Zi, Weiwei
supporting information, p. 1951 - 1961 (2022/02/09)
Enantioenriched tertiary alkyl halides are prevalent in bioactive molecules and can serve as versatile synthetic intermediates to construct complex structures. While conventional access to these motifs often hinges on stereoselective carbon-halogen or carbon-carbon bond formation reactions, desymmetric approaches using halogenated and prochiral tetrasubstituted carbons are largely elusive in comparison. Here, we report that a suite of dinuclear zinc catalysts with a prolinol- or pipecolinol-derived tetradentate ligand can reductively desymmetrize a large collection of easily available halomalonic esters to α-halo-β-hydroxyesters. These polyfunctionalized tertiary alkyl fluorides, chlorides, and bromides proved to be useful intermediates toward fluorinated drug analogs and polyhalogenated monoterpenes. The facile intramolecular epoxidation of the chiral chloride and bromide products has also enabled expeditious access to natural products containing tertiary alcohol motifs.
Conversion of nucleophilic halides to electrophilic halides: Efficient and selective halogenation of azinones, amides, and carbonyl compounds using metal halide/lead tetraacetate
Kim, Jeum-Jong,Kweon, Deok-Heon,Cho, Su-Dong,Kim, Ho-Kyun,Lee, Sang-Gyeong,Yoon, Yong-Jin
, p. 194 - 200 (2007/10/03)
AlCl3/Pb(OAc)4 and ZnBr2/Pb(OAc) 4 are efficient electrophilic N- and α-C-halogenating agents. A variety of azinones, amides and carbonyl compounds were chemoselectively and regioselectively N-, or α-C-halogenated in good to excellent yield using AlCl3/Pb(OAc)4 and ZnBr2/Pb(OAc)4 in acetonitrile. Georg Thieme Verlag Stuttgart.
2-Chloropyridazin-3(2H)-ones as electrophilic chlorinating agents: Effective α-chlorination of active methylene/methine compounds
Park, Yong-Dae,Kim, Jeum-Jong,Cho, Su-Dong,Lee, Sang-Gyeong,Falck, J. Russell,Yoon, Yong-Jin
, p. 1136 - 1140 (2007/10/03)
2,4,5-Trichloro- (2a) and 2,4-dichloro-5-methoxypyridazin-3(2H)-one (2b) are novel electrophilic chlorinating agents. α-Chlorination of active methylene/methine compounds with 2 in the presence of either Lewis or protonic acids in dichloromethane (for Lewis acid) or water (for protonic acid or none) at room temperature gave also selectively α-monochlorides and/or α,α-dichlorides in good to excellent yields.
Reactions of α,β-Unsaturated Carboxylates, Malonates and Phenylacetates with Manganese(III) Acetate in the Presence of Chloride Ions
Yonemura, Hiroshi,Nishino, Hiroshi,Kurosawa, Kazu
, p. 809 - 811 (2007/10/02)
The reaction of alkyl (E)-3-phenylpropenoates with manganese(III) acetate of Cl- ions gave alkyl (Z)-2-chloro-3-phenylpropenoates and alkyl 2,3-dichloro-3-phenylpropenoates.Ethyl (E)-2,3-diphenylpropenoate yielded ethyl 2,3-dichloro-2,3-diphenylpropanoate.Alkyl 3,3-diphenylpropenoates gave mainly alkyl 2-chloro-3,3-diphenylpropenoates.Ethyl 1-cyclohexenecarboxylate gave ethyl 1,2-dichlorocyclohexanecarboxylate.Dimethyl malonate yielded dimethyl dichloromalonate and tetramethyl 1,2-dichloro-1,1,2,2-ethanetetracarboxylate.Substituted malonates resulted in α-chloro derivatives.Methyl phenylacetates gave α-acetoxy derivatives.
