The Experts below are selected from a list of 531 Experts worldwide ranked by ideXlab platform
Peter Eilbracht - One of the best experts on this subject based on the ideXlab platform.
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application of iridium catalyzed allylic substitution reactions in the Synthesis of branched tryptamines and homologues via tandem hydroformylation Fischer Indole Synthesis
ChemInform, 2009Co-Authors: Bojan P Bondzic, Andreas Farwick, Jens X Liebich, Peter EilbrachtAbstract:Combination of enantioselective allylation reactions with a tandem hydroformylation–Fischer Indole Synthesis sequence as a highly diversity-oriented strategy for the Synthesis of tryptamines and homologues was explored. This modular approach allows the substituents at C3 of the Indole core, the type of the amine moiety, and the distance of the amine moiety to the Indole core in the final synthetic step to be defined. The starting materials required for the hydroformylation step were synthesized viairidium catalyzed enantioselective allylic substitution reactions in high yields and excellent enantioselectivities. The Rh catalyzed hydroformylation step in the presence of phenyl hydrazine, allows the in situ formed aldehyde to be trapped as the hydrazone. Subsequent acid catalyzed indolization furnishes the desired Indole structures in moderate to good yields.
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a novel access to tetrahydro β carbolines via one pot hydroformylation Fischer Indole Synthesis rearrangement of 3 3 spiroIndoleninium cations
Organic Letters, 2008Co-Authors: Bojan P Bondzic, Peter EilbrachtAbstract:The two component one-pot hydroformylation/Fischer Indole Synthesis sequence of 2,5 dihydropyrroles and phenyl hydrazines allows a facile and convenient access to tetrahydro-β-carbolines in moderate to good yields.
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2 3 disubstituted Indoles from olefins and hydrazines via tandem hydroformylation Fischer Indole Synthesis and skeletal rearrangement
Organic and Biomolecular Chemistry, 2006Co-Authors: Petra Linnepe, Axel M Schmidt, Peter EilbrachtAbstract:The tandem hydroformylation–Fischer indolisation protocol is used in the Synthesis of 2,3-disubstituted Indoles. After hydroformylation of selected olefins to form α-branched aldehydes in a one-pot procedure these are condensed with phenylhydrazine to give hydrazones. Upon acid-promoted [3,3]-sigmatropic rearrangement Indolenine intermediates with quaternary centres in the 3-position are formed, which, after selective Wagner–Meerwein-type rearrangement of one of the substituents from the 3- to the 2-position, lead to 2,3-disubstituted Indoles. Several olefins, bearing substituents with various functional groups, as well as cyclic olefinic systems are investigated.
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Synthesis of pharmacologically relevant Indoles with amine side chains via tandem hydroformylation Fischer Indole Synthesis
ChemInform, 2005Co-Authors: Axel Schmidt, Peter EilbrachtAbstract:The sequence of hydroformylation and Fischer Indole Synthesis starting from amino olefins and aryl hydrazines is described. In a convergent manner, the two units bearing pharmacologically relevant substituents are assembled in the final indolization step. This modular and diversity-oriented approach to tryptamines and homotryptamines can be conducted in water and allows Synthesis of branched and nonbranched tryptamines as well as tryptamine-based pharmaceuticals such as the 5-HT1D agonist L 775 606.
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tandem hydroformylation hydrazone formation Fischer Indole Synthesis a novel approach to tryptamides
ChemInform, 2005Co-Authors: Axel Schmidt, Peter EilbrachtAbstract:A novel one-pot Synthesis of Indole systems via tandem hydroformylation–hydrazone formation–Fischer indolization starting from allylic amides and aryl hydrazines is described. This tandem procedure directly leads to biologically interesting tryptamides and analogues.
Hosanagara N Harishkumar - One of the best experts on this subject based on the ideXlab platform.
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mild efficient Fischer Indole Synthesis using 2 4 6 trichloro 1 3 5 triazine tct
ChemInform, 2014Co-Authors: Eranna Siddalingamurthy, K M Mahadevan, Jagadeesh N Masagalli, Hosanagara N HarishkumarAbstract:The title method is advantageous with regards to functional group tolerance and the ease of product isolation.
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mild efficient Fischer Indole Synthesis using 2 4 6 trichloro 1 3 5 triazine tct
Tetrahedron Letters, 2013Co-Authors: Eranna Siddalingamurthy, K M Mahadevan, Jagadeesh N Masagalli, Hosanagara N HarishkumarAbstract:Abstract Mild and efficient protocol for the Fischer Indole Synthesis using TCT has been described. TCT serves as a mild and inexpensive catalyst. Under these conditions several functional groups such as ester, cyano, sulfone, amides, and ethers are tolerated. By this method, many functionalized analytically pure Indoles were prepared easily without the need of purification.
Cheon-gyu Cho - One of the best experts on this subject based on the ideXlab platform.
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intramolecular Fischer Indole Synthesis for the direct Synthesis of 3 4 fused tricyclic Indole and application to the total Synthesis of aurantioclavine
Organic Letters, 2016Co-Authors: Jun Park, Dong-hyun Kim, Tapas Das, Cheon-gyu ChoAbstract:Aryl hydrazides with a ketone or aldehyde containing side chains linked to the meta-position of the aromatic ring undergo acid-promoted intramolecular Fischer Indole Synthesis to generate 3,4-fused tricyclic Indoles. The preparative utility of this conceptually new synthetic approach, which does not require prefunctionalization of the Indole ring, was demonstrated by its application to a concise total Synthesis of (−)-aurantioclavine.
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Intramolecular Fischer Indole Synthesis for the Direct Synthesis of 3,4-Fused Tricyclic Indole and Application to the Total Synthesis of (−)-Aurantioclavine
2016Co-Authors: Jun Park, Dong-hyun Kim, Tapas Das, Cheon-gyu ChoAbstract:Aryl hydrazides with a ketone or aldehyde containing side chains linked to the meta-position of the aromatic ring undergo acid-promoted intramolecular Fischer Indole Synthesis to generate 3,4-fused tricyclic Indoles. The preparative utility of this conceptually new synthetic approach, which does not require prefunctionalization of the Indole ring, was demonstrated by its application to a concise total Synthesis of (−)-aurantioclavine
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intramolecular Fischer Indole Synthesis in combination with alkyne hydroarylation Synthesis of tetracyclic chromeno Indoles
ChemInform, 2014Co-Authors: Jun Park, Sunyoung Kim, Jieun Kim, Cheon-gyu ChoAbstract:Aryl hydrazides bearing a carbonyl function connected through an alkyne tether underwent an intramolecular Fischer indolization and alkyne hydroarylation in a tandem fashion to afford novel tetracyclic chromeno-Indoles. The accompanying isomerization of the 2H-chromene double bond can be avoided by stopping the tandem process at the indolophane stage and conducting the alkyne-hydroarylation reaction separately in the absence of a proton source.
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Ene-hydrazide from Enol Triflate for the Regioselective Fischer Indole Synthesis
2014Co-Authors: Byeong-yun Lim, Boeun Jung, Cheon-gyu ChoAbstract:Ene-hydrazide prepared from enol triflate undergoes a Fischer indolization reaction to give the corresponding Indole with complete regioselectivity. The starting enol triflate is readily accessed in regiochemically defined form from the ketone precursor via various well-established methods. This new protocol was successfully applied to the Synthesis of desbromoarborescidine A, a natural β-carboline alkaloid, difficult to prepare with conventional Fischer Indole Synthesis
Eranna Siddalingamurthy - One of the best experts on this subject based on the ideXlab platform.
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mild efficient Fischer Indole Synthesis using 2 4 6 trichloro 1 3 5 triazine tct
ChemInform, 2014Co-Authors: Eranna Siddalingamurthy, K M Mahadevan, Jagadeesh N Masagalli, Hosanagara N HarishkumarAbstract:The title method is advantageous with regards to functional group tolerance and the ease of product isolation.
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mild efficient Fischer Indole Synthesis using 2 4 6 trichloro 1 3 5 triazine tct
Tetrahedron Letters, 2013Co-Authors: Eranna Siddalingamurthy, K M Mahadevan, Jagadeesh N Masagalli, Hosanagara N HarishkumarAbstract:Abstract Mild and efficient protocol for the Fischer Indole Synthesis using TCT has been described. TCT serves as a mild and inexpensive catalyst. Under these conditions several functional groups such as ester, cyano, sulfone, amides, and ethers are tolerated. By this method, many functionalized analytically pure Indoles were prepared easily without the need of purification.
Jun Park - One of the best experts on this subject based on the ideXlab platform.
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intramolecular Fischer Indole Synthesis for the direct Synthesis of 3 4 fused tricyclic Indole and application to the total Synthesis of aurantioclavine
Organic Letters, 2016Co-Authors: Jun Park, Dong-hyun Kim, Tapas Das, Cheon-gyu ChoAbstract:Aryl hydrazides with a ketone or aldehyde containing side chains linked to the meta-position of the aromatic ring undergo acid-promoted intramolecular Fischer Indole Synthesis to generate 3,4-fused tricyclic Indoles. The preparative utility of this conceptually new synthetic approach, which does not require prefunctionalization of the Indole ring, was demonstrated by its application to a concise total Synthesis of (−)-aurantioclavine.
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Intramolecular Fischer Indole Synthesis for the Direct Synthesis of 3,4-Fused Tricyclic Indole and Application to the Total Synthesis of (−)-Aurantioclavine
2016Co-Authors: Jun Park, Dong-hyun Kim, Tapas Das, Cheon-gyu ChoAbstract:Aryl hydrazides with a ketone or aldehyde containing side chains linked to the meta-position of the aromatic ring undergo acid-promoted intramolecular Fischer Indole Synthesis to generate 3,4-fused tricyclic Indoles. The preparative utility of this conceptually new synthetic approach, which does not require prefunctionalization of the Indole ring, was demonstrated by its application to a concise total Synthesis of (−)-aurantioclavine
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intramolecular Fischer Indole Synthesis in combination with alkyne hydroarylation Synthesis of tetracyclic chromeno Indoles
ChemInform, 2014Co-Authors: Jun Park, Sunyoung Kim, Jieun Kim, Cheon-gyu ChoAbstract:Aryl hydrazides bearing a carbonyl function connected through an alkyne tether underwent an intramolecular Fischer indolization and alkyne hydroarylation in a tandem fashion to afford novel tetracyclic chromeno-Indoles. The accompanying isomerization of the 2H-chromene double bond can be avoided by stopping the tandem process at the indolophane stage and conducting the alkyne-hydroarylation reaction separately in the absence of a proton source.