Palladium-catalyzed intramolecular addition of amines to acetylenes. Synthesis of cyclic imines
摘要:
Intramolecular aminopalladation of alkynylamines gave intermediary alkenylpalladium compounds that hydrolyzed and isomerized to thermodynamically stable cyclic imines. Treatment of 3-alkynylamines with a catalytic amount of PdCl2(MeCN)2 gave exclusively 1-pyrrolines in good yields; 5-alkynylamines afforded 2,3,4,5-tetrahydropyridines selectively. Treatment of 4-alkynylamines with Pd(II) afforded mixtures of both 5- and 6-membered cyclic imines. Applications to the synthesis of some naturally occurring alkaloids are also described.
Et<sub>2</sub>Zn-Catalyzed Intramolecular Hydroamination of Alkynyl Sulfonamides and the Related Tandem Cyclization/Addition Reaction
作者:Yan Yin、Wenying Ma、Zhuo Chai、Gang Zhao
DOI:10.1021/jo070681h
日期:2007.7.1
Intramolecularhydroamination of alkynyl amides was effected by a catalytic amount of Et2Zn (20 mol %) to form indole derivatives, and a tandem cyclization/nucleophilic addition procedure involving reaction of the indole zinc salt intermediate with acid chlorides or halides was developed to provide an efficient approach to C3-substituted indole derivatives when an excess of Et2Zn (120 mol %) was used
Palladium(II)-Catalyzed Regioselective syn-Hydroarylation of Disubstituted Alkynes Using a Removable Directing Group
作者:Zhen Liu、Joseph Derosa、Keary M. Engle
DOI:10.1021/jacs.6b08818
日期:2016.10.5
A palladium(II)-catalyzed regioselective syn-hydroarylation reaction of homopropargyl amines has been developed, wherein selectivity is controlled by a cleavable bidentate directing group. Under the optimized reaction conditions, both dialkyl and alkylaryl alkyne substrates were found to undergo hydroarylation with high selectivity. The products of this reaction contain a 4,4-disubstituted homoallylic
已经开发了钯 (II) 催化的高炔丙基胺的区域选择性顺氢芳基化反应,其中选择性由可裂解的双齿导向基团控制。在优化的反应条件下,发现二烷基和烷芳基炔底物均以高选择性进行加氢芳基化。该反应的产物含有 4,4-二取代的高烯丙基胺基序,这在药物分子和其他生物活性化合物中很常见。
Fused ring aziridines as a facile entry into triazole fused tricyclic and bicyclic heterocycles
作者:Fang Fang、Megan Vogel、Jennifer V. Hines、Stephen C. Bergmeier
DOI:10.1039/c2ob07042a
日期:——
alkyne has provided a useful entry into triazole fused tricyclic heterocycles containing both the triazole ring and the oxazolidin-2-one ringsystem. The requisite azido-alkynes have been prepared via a two-step sequence from fused ring aziridines. A series of 6–12 membered rings containing both the oxazolidinone and triazole rings have been prepared. These ringsystems have been designed as conformationally
Palladium-Catalyzed Synthesis of Tricyclic Indoles via a N–S Bond Cleavage Strategy
作者:Bo-Sheng Zhang、Fan Wang、Xue-Ya Gou、Ying-Hui Yang、Wan-Yuan Jia、Yong-Min Liang、Xi-Cun Wang、Yuke Li、Zheng-Jun Quan
DOI:10.1021/acs.orglett.1c02715
日期:2021.10.1
bond cleavage with vinyl palladium, thus achieving a highly selective C–N coupling reaction in the Catallani–Lautens reaction system. On the basis of this discovery, a one-step synthesis of highly functionalized tricyclic indole derivatives was realized.
Zr-Catalyzed Olefin Alkylations and Allylic Substitution Reactions with Electrophiles
作者:Judith de Armas、Stanley P. Kolis、Amir H. Hoveyda
DOI:10.1021/ja000693j
日期:2000.6.1
Disubstituted aryl olefins undergo efficient alkylations in the presence of 5 mol % Cp2ZrCl2, n-BuMgCl, and alkyl tosylates or alkyl bromides. In one class of reactions (Table 1), the resulting alkyl zirconocene (initial alkylation product) undergoes β-hydride abstraction with a hydrogen atom from within the substrate to afford allylic alkylation products (Scheme 5). In another category of reactions, where cyclic