Asymetric synthesis of 1,4-diamine based chiral ligand and organocatalyst and their applications

Ortaylı, Oytun
Novel 1,4-chiral diamine ligand possessing a trans-9,10-dihydro-9,10-ethanoanthracene backbone was synthesized. The synthetic plan involves first LiAlH4 reduction of the Diels-Alder adduct obtained by reaction of dimenthyl fumarate and anthracene, which is followed by reacting the corresponding alcohol and subsequent attachment of mesylate and triflate units to get good leaving groups which are available substances for introducing nitrogen units via SN2 type reactions. Consequently, by using dimesyl ester and ditriflate esters five catalysts 27, 29, 30, 33 and 38 were synthesized. The first four catalysts 27, 29, 30 and 33 were used in transfer hydrogenation reactions with transition metal whereas catalyst 38 used as an organocatalyst in direct aldol reaction between acetone and p-nitrobenzaldehyde.


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...
Asymmetric synthesis of 1,4-amino alcohol ligands with a norbornene backbone for use in the asymmetric diethylzinc addition to benzaldehyde
Tanyeli, Cihangir (Elsevier BV, 2005-06-06)
The asymmetric synthesis of cis-1,4-amino alcohols with a norbornene backbone was performed starting with (2S,3R)(-)-cis-hemiester 2 (98% ee). Chemoselective amination with NH4OH and HMPTA followed by LAH reduction afforded 5 and 7. respectively. Amido ester 6 was transformed into chiral ligand 9 with Grignard reaction followed by LAH reduction. The chiral ligands 5. 7. and 9 were subjected to asymmetric diethylzinc addition to examine their effectiveness as chiral catalysts. Among these, c chiral ligand 7 ...
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.
Synthesis of novel norephedrine-based chiral ligands with multiple stereogenic centers and their application in enantioselective addition of diethylzinc to aldehyde and chalcone
Unaleroglu, C; Aydin, AE; Demir, Ayhan Sıtkı (Elsevier BV, 2006-03-06)
Novel norephedrine-based chiral ligands with multiple stereogenic centers were conveniently prepared from norephedrine and N-substituted pyrrole. These novel chiral ligands were used to catalyze the enantioselective addition of diethylzinc to aldehydes and to chalcone in high yields and with good to high enantioselectivities. The absolute configuration of products was found to be affected by the stereogenic centers on the norephedrine part of the novel chiral ligands.
Chemoenzymatic synthesis of 2-ethyl-5-hydroxy-3- methoxy-cyclopent-2-enone
Dalfidan, Çağla; Demir, Ayhan Sıtkı; Department of Chemistry (2005)
Chiral hydroxylated cyclopentane derivatives are important precursors for biologically active compounds. Synthesis of these types of compounds in optically pure form found increased interest in pharmaceutical chemistry. 2-ethyl-cyclopentane-1.3-dione was acetoxylated using manganese III acetate at preferred positions. Enzyme catalyzed enantioselective hydrolysis or enantioselective acetoxylation of hydrolyzed acetoxy derivatives gives the corresponding hydroxylated diketones in optically pure form.
Citation Formats
O. Ortaylı, “Asymetric synthesis of 1,4-diamine based chiral ligand and organocatalyst and their applications,” M.S. - Master of Science, Middle East Technical University, 2010.