Chiral 2-aminodmap/sulfonamides and squaramides as bifunctional acid/base organocatalysts in asymmetric catalysis

Işık, Murat
Synthesis and evaluation of catalytic performances of novel bifunctional 2- aminoDMAP-Thiourea/ Sulfonamide/ Squaramide organocatalysts derived from trans-(R,R)-cyclohexane-1,2-diamine forms the main goal of this thesis. For this purpose, direct selective mono-N-pyridilization of trans-(R,R)-cyclohexane-1,2- diamine via Pd and Cu catalysis is described successfully first. Facile preparation of chiral 2-aminoDMAP core catalaphore led to the development of various 2- aminoDMAP- Thiourea/ Sulfonamides/ Squaramides as bifunctional acid/base organocatalyst libraries (most in two-steps overall) which showed good results in asymmetric conjugate addition of 1,3-dicarbonyls to trans-(β)-nitrostyrene. Enantiomeric excesses (ee) up to 93% were attained.


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...
Gold catalyzed synthesis of pyrrole and indole fused heterocycles via alkyne cyclization
Aslan Taşkaya, Sultan; Balcı, Metin; Department of Chemistry (2015)
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...
Asymmetric synthesis of chiral camphor fused pyridine type novel organocatalysts
Küçükdişli, Murat; Tanyeli, Cihangir; Department of Chemistry (2009)
Chiral pyridines as organocatalysts have been used in asymmetric organic synthesis in recent years. The asymmetric synthesis of camphor fused pyridine type novel organocatalysts were perfomed starting from cheap and easily available natural (+)-camphor. Using camphor fused pyridine skeleton, six organocatalysts 29, 32, 33, 38, 40, and 41were successfully synthesized. The first four nucleophilic and Lewis base catalysts 29, 32, and 33 are different P-oxides and P,N-dioxides which were tested in allylation of...
Synthesis of chiral diene systems via ring closing enyne metathesis and their applications in diels-alder reactions
Çayır, Merve; Tanyeli, Cihangir; Department of Chemistry (2010)
The main subject of this thesis is synthesis of chiral diene systems via Ring Closing Enyne Metathesis (RCEM). Furan and thiophene carbaldehydes were chosen as starting compounds. As a result of allylation and propargylation reaction of these aldehydes targeting racemic heteroaryl substituted homoallylic and homopropargylic alcohols were synthesized. Enantiomerically enriched alcohols were obtained by enzymatic resolution method with different enzymes (PS-II, Lipozyme) with the high enantiomeric excess valu...
Synthesis of novel chiral bisoxazoline ligands with a norbornadiene backbone: use in the copper-catalyzed enantioselective Henry reaction
Delikus, Rabia; Cakir, Emine; DEMİREL, NADİR; Balcı, Metin; KARATAŞ, BETÜL (The Scientific and Technological Research Council of Turkey, 2016-01-01)
Novel chiral bisoxazoline ligands based on norbornadiene were synthesized and used for the asymmetric Henry reaction. Various aromatic aldehydes were converted into chiral beta-nitro alcohols with high yields and moderate to acceptable enantioselectivities under the optimized reaction conditions.
Citation Formats
M. Işık, “Chiral 2-aminodmap/sulfonamides and squaramides as bifunctional acid/base organocatalysts in asymmetric catalysis,” Ph.D. - Doctoral Program, Middle East Technical University, 2011.