Total synthesis of the cyclic monoterpenoid pyrano[3,2-<i>a</i>]carbazole alkaloids derived from 2-hydroxy-6-methylcarbazole
作者:Cemena Gassner、Ronny Hesse、Arndt W. Schmidt、Hans-Joachim Knölker
DOI:10.1039/c4ob01151a
日期:——
The synthesis of seven pyrano[3,2-a]carbazole alkaloids has been achieved using their putative biogenetic precursor 2-hydroxy-6-methylcarbazole as key intermediate.
Palladium-Catalyzed Intramolecular C-H Amination in Water
作者:Lizheng Yang、Hao Li、Haifei Zhang、Hongjian Lu
DOI:10.1002/ejoc.201601043
日期:2016.12
found to be effective for intramolecular C–H amination in water. With 2-azidobiphenyls as substrates, the reaction efficiently provided various carbazoles with N2 as the sole byproduct. The reaction showed high functional-group tolerance and could be used in the synthesis of several natural carbazole alkaloids. The catalytic process was promoted by water, and the reaction was inefficient in the organic
发现钯 (II) 催化对水中的分子内 C-H 胺化有效。以 2-叠氮联苯为底物,该反应有效地提供了各种咔唑,N2 作为唯一的副产物。该反应显示出高官能团耐受性,可用于合成多种天然咔唑生物碱。催化过程受水促进,在所研究的有机溶剂中反应效率低下。
Self-Assembled Multilayer Iron(0) Nanoparticle Catalyst for Ligand-Free Carbon–Carbon/Carbon–Nitrogen Bond-Forming Reactions
Self-assembled multilayer iron(0) nanoparticles (NPs, 6–10 nm), namely, sulfur-modified Au-supported Fe(0) [SAFe(0)], were developed for ligand-free one-pot carbon–carbon/carbon–nitrogen bond-formingreactions. SAFe(0) was successfully prepared using a well-established metal–nanoparticle catalyst preparative protocol by simultaneous in situ metal NP and nanospace organization (PSSO) with 1,4-bis(trimethylsilyl)-1
Visible-light-promoted intramolecular C–H amination in aqueous solution: synthesis of carbazoles
作者:Lizheng Yang、Yipin Zhang、Xiaodong Zou、Hongjian Lu、Guigen Li
DOI:10.1039/c7gc03392c
日期:——
An effective and operationally simpleprotocol is reported for the synthesis of versatile carbazoles. With water as a co-solvent, visible-light rather than various metals is used to facilitate the conversion of readily available 2-azidobiphenyls under mild conditions. Various functionalized bioactive natural alkaloids, such as glycoborine, clausine C, clausine L, clausine H and clauszoline K, were
Biphilic Organophosphorus-Catalyzed Intramolecular C<sub>sp<sup>2</sup></sub>–H Amination: Evidence for a Nitrenoid in Catalytic Cadogan Cyclizations
作者:Trevor V. Nykaza、Antonio Ramirez、Tyler S. Harrison、Michael R. Luzung、Alexander T. Radosevich
DOI:10.1021/jacs.7b13803
日期:2018.2.28
equiv of phosphetane P-oxide 3·[O] and 2-nitrosobiphenyl. Experimental and computationalinvestigations into the C-N bond forming event suggest the involvement of an oxazaphosphirane (2 + 1) adduct between 3 and 2-nitrosobiphenyl, which evolves through loss of phosphetane P-oxide 3·[O] to give the observed carbazole product via C-H insertion in a nitrene-like fashion.