Gold catalyzed synthesis of pyrrole and indole fused heterocycles via alkyne cyclization

Aslan Taşkaya, Sultan
New methodologies were developed for the synthesis of pyrrolo- and indolo-oxazin1-one derivatives. In the first section of this thesis, various N-propargyl pyrrole and indole esters were efficiently converted into corresponding carboxylic acids which then underwent intramolecular cyclization reaction with AuCl3 to give 6-exo-dig cyclization products. In the second part of the study, 6-exo-dig pyrrolo- and indolo- oxazinone derivatives were treated with TFA in order to achieve double bond isomerization. Some of the 6-exo-dig cyclic double bonds underwent isomerization to 6-endo-cyclic compounds upon treatment with TFA. The experimental results were supported by DFT calculations. Moreover, the cyclization reaction of 1-prop-2-ynyl1H-pyrrole-2-carboxylic acid in the presence of alcohols catalyzed by Au(I) resulted in the formation of hemiacetals after cascade reactions.


Base-promoted synthesis of new diazepine derivatives via alkyne cyclization
Baskın, Dılgeş; Balcı, Metin; Department of Chemistry (2016)
A new methodology was developed for the synthesis of dipyrromethane and diazepine derivatives. In the first section of this thesis, synthesis of various dipyrromethanes from aromatic aldehydes was carried out. Dipyrromethanes were used as starting materials for the next step. In the second part of the study, introduction of a propargyl group to nitrogen atom to one of pyrrole units of dipyrromethane gave the expected mono-propargylated compounds which were the key compounds for further cyclization reactions...
Synthesis of dipyrrolo-diazepine derivatives via intramolecular alkyne cyclization
Baskin, Dilges; Cetinkaya, Yasin; Balcı, Metin (2018-07-26)
A regioselective approach was developed for the synthesis of dipyrrolo-diazepine derivatives. The synthetic route to dipyrrolo-diazepines first involves the synthesis of dipyrromethanes, followed by reaction of propargyl bromide in the presence of NaH to attach one alkyne functionality to the pyrrole nitrogen atom. Intramolecular heterocyclization with NaH in DMF between the alkyne functionality and pyrrole nitrogen atom gave the desired structures in good yields.
Nucleophilic and electrophilic cyclization reactions of n-alkyne substituted pyrrole derivatives
Yenice, Işıl; Balcı, Metin; Department of Chemistry (2016)
Pyrrolopyrazinone, triazinone and oxazinone derivatives were synthesized via practical methodologies. In the study, N-alkyne substituted pyrrole esters were synthesized and isolated as key compounds via copper catalyzed cross-coupling reaction. Then, key compounds underwent nucleophilic cyclization reaction with hydrazine monohydrate to yield pyrrolopyrazinone and/or pyrrolotriazinone derivatives according to electronic properties of group attached to alkyne unit. Additional study was the synthesis of pyrro...
Stereoselective construction of 2-oxindole fused spirocycle precursors /
Karahan, Seda; Tanyeli, Cihangir; Department of Chemistry (2019)
Recent literature on the bioactivity of isatin (indoline-2,3-dione) derivatives triggered organic chemists to make use of the unique potential of isatin in asymmetric organocatalytic synthesis. Due to extensive presence of 2-oxindole skeleton, especially spiro-fused cycles, in many natural products, they drew the special interest in the disciplines of medicinal chemistry and agrochemistry. Due to highly reactive prochiral carbonyl group, isatins are potent precursors for the synthesis of 3,3-disubstituted s...
Endohedrally halogen and interhalogen substituted C-70-AM1 study
Türker, Burhan Lemi (2002-12-09)
C-70 structure having a certain halogen (Cl-2, Br-2, I-2) or interhalogen molecule (BrCl, ICl, IBr) as the endohedral substituent was considered for semiempirical quantum chemical calculations at the level of AMI (RHF). All the endohedrally monosubstituted systems were found to be stable (inversely related to the bulkiness of the substituent) but endothermic (directly related to the size of the substituent). Some electronic and physicochemical properties of these systems were also reported.
Citation Formats
S. Aslan Taşkaya, “Gold catalyzed synthesis of pyrrole and indole fused heterocycles via alkyne cyclization,” M.S. - Master of Science, Middle East Technical University, 2015.