Catalytic Enantioselective Alkene Aminohalogenation/Cyclization Involving Atom Transfer
作者:Michael T. Bovino、Sherry R. Chemler
DOI:10.1002/anie.201109044
日期:2012.4.16
the synthesis of chiral 2‐bromo, chloro, and iodomethyl indolines and 2‐iodomethyl pyrrolidines (see scheme). Stereocenter formation is believed to occur by enantioselective cis aminocupration and CX bond formation is believed to occur by atom transfer. The ultility of the products as versatile synthetic intermediates was demonstrated, as was a radical cascade cyclization sequence.
已解决的问题:标题反应用于合成手性 2-溴、氯和碘甲基二氢吲哚和 2-碘甲基吡咯烷(参见方案)。立体中心的形成被认为是通过对映选择性顺式 氨基氧化发生的,C X 键的形成被认为是通过原子转移发生的。证明了产品作为多功能合成中间体的实用性,以及自由基级联环化序列。
Highly Selective Palladium-Catalyzed Intramolecular Chloroamination of Unactivated Alkenes by Using Hydrogen Peroxide as an Oxidant
作者:Guoyin Yin、Tao Wu、Guosheng Liu
DOI:10.1002/chem.201102776
日期:2012.1.9
Cheap and clean! A novel Pd‐catalyzed oxidative intramolecularchloroamination of unactivatedalkenes has been developed by usinghydrogenperoxide as an oxidant and CaCl2 as a chlorine source. A series of chlorinated piperidine derivatives has been obtained with high regio‐ and diastereoselectivities at room temperature (see scheme).
Enantioselective copper-catalyzed cyclization of γ-alkenylsulfonamides and a δ-alkenylsulfonamide in the presence of a range of vinyl arenes results in variously functionalized 2-substituted chiral nitrogen heterocycles via a formal alkene C-H functionalization process. Application of this reaction to the concise synthesis of a 5-HT(7) receptor antagonist is demonstrated.
mCPBA-mediated metal-free intramolecular aminohydroxylation and dioxygenation of unfunctionalized olefins
作者:Gong-Qing Liu、Lin Li、Lili Duan、Yue-Ming Li
DOI:10.1039/c5ra09024e
日期:——
mCPBA-mediated metal-free intramolecular aminohydroxylation and dioxygenation reactions of unfunctionalizedolefins are reported. In the presence of 1.2 equiv. of m-chlorobenzoic peracid, different N-sulfonyl 4-penten-1-amine substrates could be cyclized via epoxide intermediates, producing the corresponding 2-hydroxymethylpyrrolidine products in up to 92% yields. The reaction could be carried out
Flexible Gold-Catalyzed Regioselective Oxidative Difunctionalization of Unactivated Alkenes
作者:Teresa de Haro、Cristina Nevado
DOI:10.1002/anie.201005763
日期:2011.1.24
AuI/AuIIIcatalyticcycles can trigger three highly regioselective alkene difunctionalization processes that involve the formation of C(sp3)O, C(sp3)N, and C(sp3)C(sp2) bonds. The reaction can proceed by reductive elimination on the oxidized gold center with complete retention of the configuration or through two subsequent nucleophilic substitution reactions via an aziridine intermediate.