50650-98-1

Upstream product

• 15128-52-6 1,2,3,9-tetrahydro-4H-carbazol-4-one 
• 98-59-9 p-toluenesulfonyl chloride 
• 942-01-8 1,2,3,4-tetrahydrocarbazole 
• 170456-80-1 3-iodo-1-tosyl-1-indole 
• 92841-24-2 6-hydroxy-4,5-dihydro-[1,1'-biphenyl]-2(3H)-one 
• 504-02-9 1,3-cylohexanedione 
• 591-50-4 iodobenzene 

Relevant academic research and scientific papers

Enantioselective Synthesis of 1- and 4-Hydroxytetrahydrocarbazoles through Asymmetric Transfer Hydrogenation

Several 1- and 4-hydroxytetrahydrocarbazoles were prepared in high yields (up to 99%) and excellent enantiomeric excesses (up to >99% ee) from the corresponding 1- and 4-oxotetrahydrocarbazoles through asymmetric transfer hydrogenation by using the commercially available Noyori-Ikariya ruthenium catalyst. The immediate use of the freshly prepared catalyst and the use of a HCO 2 H-DABCO (11:6) mixture as the hydrogen source are crucial for achieving high activity and enantioselectivity. In this way, a tetrahydrocarbazole heterocycle fused to a lactone moiety was synthesized in 45% yield and 97% ee.

Regioselective Transition-Metal-Free Oxidative Cyclobutanol Ring Expansion to 4-Tetralones

A facile and transition-metal-free ring expansion of the cyclobutanol moiety to 4-tetralones fused to heteroaromatic systems is described. The oxidative ring expansion proceeds rapidly and regioselectively through mediation by N-bromosuccinimide and aceto

Fine-tuning hydroxylamines as single-nitrogen sources for Pd(0)-catalyzed diamination of o-bromo(or chloro)-biaryls

Transition metal-catalyzed diamination by hydroxylamines is a common approach for making three-membered aziridines, while its use for building the larger N-heterocycles is still underdeveloped. Herein, we report an efficient Pd(0)-catalyzed inter-molecular [4+1] annulation of o-bromo(or chloro)-biaryls with bifunctional secondary hydroxylamines for the one-step assembly of synthetically useful carbazoles. Noteworthily, a linchpin for this domino reaction was the judicious selection of both the amino-sources and Pd(0)-catalysts for enabling the prerequisite oxidative addition of aryl halides to Pd(0)-species in the presence of hydroxylamines with a labile N-O bond. [Figure not available: see fulltext.].

Regioselective synthesis of 1- and 4-tetralones from heteroaryl-3-cyclobutanols

Herein we describe the first transition-metal-free ring expansion of four-membered rings to 1-tetralones from 3-substituted heteroaromatic compounds, and the first example of an oxetanol ring expansion to an oxa-tetralone. We also experimentally investiga

Transition-Metal-Free Access to Heteroaromatic-Fused 4-Tetralones by the Oxidative Ring Expansion of the Cyclobutanol Moiety

Advances in the transition-metal-free cyclobutanol ring expansion to 4-tetralones under N-bromosuccinimide mediation are described. We have expanded the scope of this ring expansion methodology and investigated the effect substituents on the aromatic ring, and the cyclobutanol moiety, have on the outcome of the reaction. Limitations with certain substituents on the cyclobutanol moiety are also described. Further experimental evidence to support our mechanistic understanding is disclosed, and we now preclude the suggested involvement of a primary radical for this transformation.

Studies on the enantioselective synthesis of carbazolones as intermediates in aspidosperma and kopsia alkaloid synthesis

Two strategies for the assembly of homochiral carbazolones have been investigated. The first exploited desymmetrisation of 1,3-cyclohexadione derivatives however this failed to deliver satisfactory outcomes. An orthogonal route exploiting palladium catalysed decarboxylative allylation of racemic carbazolone β-ketoesters has been developed. Herein we report full details on the development of this reaction and clarify apparent discrepancies between our preliminary reports and those of Shao.

Molecular structure and reactivity of the 1,2-dihydrocarbazol-4(3H)-one: X-ray crystal structure of N-methyl and N-(p-methylbenzenesulfonyl) derivatives

Synthesis and reactivity analysis of the 1,2-dihydrocarbazol-4(3H)-one, and the N-methyl, N-tosyl and 2,2-dimethyl derivatives have been carried out.Molecular structures of the N-methyl and N-tosyl derivatives have been analyzed by X-ray diffraction.Crystals of the N-methyl derivative are monoclinic, space group P21/c, a=8.868(1), b=16.652(1), c=7.5440(4) Angstroem, β=113.657(3).Crystals of the N-tosyl derivative are monoclinic, P21/c, a=12.0016(3), b=8.9178(2), c=16.0485(4) Angstroem, β=104.372(2).An extended conjugation from the carbonyl group to the nitrogen atom and an envelope conformation for the common cyclohexenone fragment are evident in both cases.Oximation and Beckmann rearrangement, and etherification of the carbonyl group is reported.KEY WORDS: Synthesis, reactivity, tetrahydrocarbazol-4-one.