87167-66-6Relevant academic research and scientific papers
Oxidative Pd(II)-catalyzed C-H bond amination to carbazole at ambient temperature
Jordan-Hore, James A.,Johansson, Carin C. C.,Gulias, Moises,Beck, Elizabeth M.,Gaunt, Matthew J.
supporting information; experimental part, p. 16184 - 16186 (2009/05/08)
We report a new Pd(II)-catalyzed C-H bond amination reaction to form carbazoles, an important motif that is prevalent in a range of systems. The catalytic amination process operates under extremely mild conditions and produces carbazole products in good to excellent yields. Carbazoles possessing complex molecular architecture can also be formed using this reaction, highlighting its potential in natural product synthesis applications. Preliminary mechanistic investigations reveal the reaction proceeds through a Pd(II)/Pd(IV) manifold and that reductive elimination from a high oxidation state Pd(IV) complex facilitates the mild conditions of this transformation. Copyright
Synthetic Studies of Indoles and Related Compounds, Part 221. The Vilsmeier-Haack Reaction of N-Benzyl-1,2,3,4-tetrahydrocarbazoles and its Synthetic Application to Olivacine and Ellipticine2
Yokoyama, Yuusaku,Okuyama, Naomi,Iwadate, Shinji,Momoi, Tokuko,Murakami, Yasuoki
, p. 1319 - 1329 (2007/10/02)
Vilsmeier-Haack reaction of 9-benzyl-1,2,3,4-tetrahydrocarbazole (18a) at 120 deg C gave 9-benzyl-1-methylcarbazole-3-carbaldehyde (19a) and 9-benzyl-1-(N,N-(dimethylamino)methyl)carbazole-3-carbaldehyde (22a) in moderate yields, whereas, the same reaction at 0 deg C gave 9-benzyl-1,2,3,4-tetrahydrocarbazole-1-carbaldehyde (20a) in very good yield.The aldehyde (20a) was converted into 9-benzyl-1-methylcarbazole (21a) by another Vilsmeier-Haack reaction.This carbazole (21a) unexpectedly underwent non-regioselective formylation under similar reaction conditions to give a mixture of compound (19a) and 9-benzyl-8-methylcarbazole-3-carbaldehyde (23a).On the basis of the above results, a mechanism of the formation of the aromatic aldehyde (19a) was proposed, which involves 1,5-sigmatropic rearrangement of an N-methylidene dimethylammonium cation from the 4a-position to the 3-position as a key step.Vilsmeier-Haack reaction of 9-benzyl-1,2,3,4-tetrahydro-4-methylcarbazole (18b) at 100 deg C also gave 9-benzyl-1,4-dimethylcarbazole-3-carbaldehyde (19b) in moderate yield.The total syntheses of two antitumor alkaloids, olivacine (10) and ellipticine (11), were achieved by utilizing compounds (19a) and (19b) as key intermediates.
THE VILSMEIER-HAACK REACTION OF N-ALKYL-1,2,3,4-TETRAHYDROCARBAZOLES AND THE SYNTHETIC APPLICATION TO OLIVACINE AND ELLIPTICINE
Murakami, Yasuoki,Yokoyama, Yuusaku,Okuyama, Naomi
, p. 2189 - 2192 (2007/10/02)
The mechanism of the formation of products resulting from the Vilsmeier-Haack reaction of N-alkyl-1,2,3,4-tetrahydrocarbazoles, and the synthetic application to olivacine and ellipticine, are described.
