Publications (4) View all
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Article: C2-Symmetric Cyclic Selenium Catalyzed Enantioselective Bromoaminocyclization.
Feng Chen, Chong Kiat Tan, Ying-Yeung Yeung[show abstract] [hide abstract]
ABSTRACT: A catalytic asymmetric bromocyclization of tri-substituted olefinic amides is reported using a C2-symmetric mannitol-derived cyclic selenium catalyst and stoichiometric amount of N-bromophthalimide. The resulting enantioenriched pyrrolidine products, which contain two stereogenic centers, could undergo rearrangement to yield 2,3-disubstituted piperidine in excellent diastereoselectivity and enantiospecificity.Journal of the American Chemical Society 01/2013; · 9.91 Impact Factor -
Article: Studies toward Lewis basic thiocarbamate and thiourea mediated bromolactonization: the effect of a trace amount of water on the reactivity and enantioselectivity
Chong Kiat Tan, Feng Chen, Ying-Yeung YeungTetrahedron Letters 09/2011; 52(38):4892-4895. · 2.68 Impact Factor -
Article: Asymmetric bromolactonization using amino-thiocarbamate catalyst.
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ABSTRACT: A novel amino-thiocarbamate-catalyzed bromolactonization of unsaturated carboxylic acids has been developed. The scope of the reaction is evidenced by 22 examples of γ-lactones with up to 99% yield and 93% ee. The protocol was applied in the enantioselective synthesis of the key intermediates of VLA-4 antagonists.Journal of the American Chemical Society 10/2010; 132(44):15474-6. · 9.91 Impact Factor -
Article: Molecular sieves as an efficient and recyclable catalyst for bromolactonization and bromoacetoxylation reactions
Tetrahedron Letters 06/2010; 51(26):3433-3435. · 2.68 Impact Factor