Copper-catalyzed asymmetric conjugate addition of diethylzinc to substituted chalcones using a chiral phosphine ligand

Doğan, Özdemir
Polat, Savas
Tecimer, M. Ali
A series of chiral phosphine PFAM and phosphine oxide POFAM ligands were studied for the copper-catalyzed asymmetric diethylzinc addition to enones. One of these ligands, PFAM2, was an efficient catalyst with a variety of enones to give conjugate addition products in up to 96% yield and 92% ee.


alpha-Tricalcium phosphate hydrolysis to hydroxyapatite at and near physiological temperature
Durucan, Caner (2000-06-01)
The kinetics of hydroxyapatite (HAp) formation by direct hydrolysis of alpha-tricalcium phosphate (alpha-TCP) [alpha-Ca-3(PO4)(2)] have been investigated. Transformation kinetics were examined for reactions at 37 degrees C, 45 degrees C and 56 degrees C by isothermal calorimetric analysis. Setting times and morphologies of the resultant HAp were found to be strongly dependent on reaction temperature. XRD analysis accompanied by FTIR confirmed that phase pure calcium-deficient hydroxyapatite (CDHAp) [Ca10-x(...
Potassium permanganate/ carboxylic acid/ organic solvent: a powerful reagent for c-c bond formation, aryl coupling reactions and enone oxidation ipso-nitration of arylboronic acids with silver nitrite/ tmscl
Fındık, Hamide; Demir, Ayhan Sıtkı; Department of Chemistry (2009)
The first part of the thesis presents the KMnO4/ carboxylic acid/ organic solvent which is a powerful reagent for C-C bond formation, aryl coupling reactions and enone oxidation. The a¢-acetoxylation of enones and the a-acetoxylation of aromatic ketones were carried out with potassium permanganate and acetic acid, in which acetoxylation products were obtained in 74-96% yields. The same reaction was carried out with carboxylic acids other than acetic acid, which furnished corresponding acyloxy ketones with t...
Metal triflates-catalyzed conjugate addition of homochiral Pyrroles to alpha,beta-unsaturated esters
Unaleroglu, C; Temelli, B; Demir, Ayhan Sıtkı (Georg Thieme Verlag KG, 2004-10-18)
The Friedel-Crafts reaction of homochiral pyrrole derivatives with alpha,beta-unsaturated esters catalyzed by metal triflates furnished conjugate addition products. The best yields were obtained by using yttrium triflate and methyl 4-phenyl-2-oxobut-3-enoate (2a). The addition worked regioselectively at C-5 of pyrrole. The diastereoisomers were separated by column chromatography.
Cobalt Metallopeptide Electrocatalyst for the Selective Reduction of Nitrite to Ammonium
Guo, Yixing; Stroka, Jesse R.; Kandemir, Banu; Dickerson, Claire E.; Bren, Kara L. (American Chemical Society (ACS), 2018-12-12)
A cobalt-tripeptide complex (CoGGH) is developed as an electrocatalyst for the selective six-electron, eight-proton reduction of nitrite to ammonium in aqueous buffer near neutral pH. The onset potential for nitrite reduction occurs at -0.65 V vs Ag/AgCl (1 M KCl). Controlled potential electrolysis at -0.90 V generates ammonium with a faradaic efficiency of 90 +/- 3% and a turnover number of 3550 +/- 420 over 5.5 h. CoGGH also catalyzes the reduction of the proposed intermediates nitric oxide and hydroxylam...
Gold-Catalyzed Oxime-Oxime Rearrangement
Guven, Sinem; Ozer, Merve Sinem; Kaya, Serap; Menges, Nurettin; BALCI, METİN (2015-06-05)
The gold-catalyzed reaction of pyrrole and indole oximes having a propargyl group attached to the nitrogen atom was studied. The selective 6-endo-dig mode of cyclization was observed for the terminal alkynes giving rise to the formation of pyrazine N-oxides in the presence of a gold catalyst. However, the reaction with substituted alkyne transferred the oxime functionality intramolecularly from one carbon atom to another via the 7-endo-dig cyclization process. This transformation is unprecedented in the lit...
Citation Formats
Ö. Doğan, S. Polat, and M. A. Tecimer, “Copper-catalyzed asymmetric conjugate addition of diethylzinc to substituted chalcones using a chiral phosphine ligand,” TETRAHEDRON-ASYMMETRY, pp. 1601–1604, 2011, Accessed: 00, 2020. [Online]. Available: