在此,我们报告Cp * Co III催化的C H活化方法是创建高度有价值的异喹诺酮和吡啶酮的重要步骤,这些异喹啉酮和吡啶酮可以轻松地用于各种芳香族素,原小ber碱和tylophora生物碱的总合成。这种特殊的CH活化/环化反应是通过多个末端以及内部炔烃偶联伙伴实现的,具有广泛的应用范围和出色的官能团耐受性。本文报道的该方案的合成适用性已在两个Topo-I-抑制剂和两个8-氧代小ber碱核心的合成中得到了证明,这些核心可进一步制成四氢小ber碱和原小ber碱生物碱。此外,这些构件也以方便的方式转化为六种不同的tylophora生物碱。
Rhodium(III)-Catalyzed Intramolecular Annulation through CH Activation: Total Synthesis of (±)-Antofine, (±)-Septicine, (±)-Tylophorine, and Rosettacin
作者:Xianxiu Xu、Yu Liu、Cheol-Min Park
DOI:10.1002/anie.201204970
日期:2012.9.10
Annulation: The efficient synthesis of 3‐hydroxyalkyl isoquinolones and 6‐hydroxyalkyl 2‐pyridones is enabled through the intramolecular annulation of alkyne‐tethered hydroxamic esters (see scheme, Cp*=pentamethylcyclopentadienyl). The reaction features high regioselectivity, broad substrate scope, and excellent functional‐group tolerance, proceeds under mild reaction conditions with low catalyst loading
Formal Synthesis of Indolizidine and Quinolizidine Alkaloids from Vinyl Cyclic Carbonates
作者:Àlex Cristòfol、Christian Böhmer、Arjan W. Kleij
DOI:10.1002/chem.201904223
日期:2019.11.27
groups in complex multistep synthetic routes. This study shows that a concise, yet modular synthesis of indolizidine and quinolizidine alkaloids can be developed from vinyl-substituted cyclic carbonate (VCC) intermediates. Through a highly stereoselective palladium-catalyzed allylic alkylation reaction, these alkaloid motifs can be assembled in four synthetic and only two column purification steps. The
Total synthesis of the tylophora alkaloids rusplinone, 13aα-secoantofine, and antofine using a multicatalytic oxidative aminochlorocarbonylation/Friedel–Crafts reaction
作者:Lisa M. Ambrosini、Tim A. Cernak、Tristan H. Lambert
DOI:10.1016/j.tet.2010.03.021
日期:2010.6
A rapid synthetic approach to the tylophora alkaloids antofine and 13aα-secoantofine is presented that makes use of a multicatalytic oxidative aminochlorocarbonylation/Friedel–Crafts reaction as the key step. This reaction, along with a one-pot, three-step telescoped process offers a three or four-pot sequence to access the title compounds in high overall yield.
Cyano Group Removal from Cyano-Promoted Aza-Diels–Alder Adducts: Synthesis and Structure–Activity Relationship of Phenanthroindolizidines and Phenanthroquinolizidines
Phenanthroindolizidines and phenanthroquinolizidines were concisely synthesized by the reductive decyanization of cyano-promoted intramolecular aza-Diels–Alder cycloadducts followed by aryl–aryl coupling. Cyano groups were removed from α-aminoacrylonitriles via treatment with sodium borohydride in 2-propanol in almost quantitative yields; a possible mechanism was proposed and examined using D-labeling experiments
Rapid entry to phenanthroindolizidine alkaloids <i>via</i> an acid-catalysed acyliminium ion-electrocyclization cascade
作者:Max St. Pierre、Christine J. Kempthorne、David K. Liscombe、James McNulty
DOI:10.1039/d3ob01359f
日期:——
A rapid total synthesis of seco-phenanthroindolizidine alkaloids was achieved involving a one-pot acid catalyzed deprotection- condensation-electrocyclization strategy. This synthetic route provided a concise synthesis of (±)-seco-antofine and (±)-septicine in only 4 steps with an overall yield of 22% and 17%, respectively.