Asymmetric aldol addition of alpha-azido ketones to ethyl pyruvate mediated by a cinchona-based bifunctional urea catalyst

Date

2014-07-30

Author

Okumus, Seda
Tanyeli, Cihangir
Demir, Ayhan Sıtkı

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

300
views

0
downloads

The first asymmetric synthesis of ethyl 4-aryl-3-azido-2-hydroxy-2-methyl-4-oxobutanoates via a cinchona organocatalyst induced aldol addition of alpha-azido ketones to ethyl pyruvate has been developed. The coupling reaction under optimized conditions was carried out to furnish tetrafunctionalized synthons with enantioselectivities of up to 91:9 and enriched diastereoselectivities of up to 95:5 (syn:anti).

Subject Keywords

Organic Chemistry, Biochemistry, Drug Discovery

URI

https://hdl.handle.net/11511/47300

Journal

TETRAHEDRON LETTERS

DOI

https://doi.org/10.1016/j.tetlet.2014.06.018

Collections

Department of Chemistry, Article

Suggestions

OpenMETU
Core

Distyryl-boradiazaindacenes: facile synthesis of novel near IR emitting fluorophores Dost, Zeynep; Atilgan, Serdar; Akkaya, Engin U. (Elsevier BV, 2006-09-04) Boradiazaindacenes with methyl substituents at 3 and 5 positions were for the first time shown to undergo efficient double condensation reactions with an aromatic aldehyde yielding a series of extended conjugation dyes. These new fluorophores have absorption maxima in the range of 650-660 nm. The dyes reported here have large quantum yields with 20 nm Stokes' shifted emission peaks. The straightforward synthesis of such red shifted BODIPY derivatives is important in relation to the synthesis of novel and us...
Reinvestigation of the synthetic and mechanistic aspects of Mn(III) acetate mediated oxidation of enones Demir, Ayhan Sıtkı; Reis, O; Igdir, AC (Elsevier BV, 2004-04-05) Mn(OAc)(3) mediated alpha'-acetoxylation of alpha,beta-unsaturated enones is reinvestigated from a synthetic and mechanistic point of view and an improved procedure based on the use of acetic acid as a co-solvent is presented. Excellent results were obtained for a variety of structurally diverse and synthetically important enones under the optimized conditions.
Intermolecular heterocyclization of alkynones with 2-mercaptoacetaldehyde under metal-free conditions: synthesis of 2,3-disubstituted thiophenes Vatansever, Erol Can; Kilic, Kubra; Ozer, Merve Sinem; KOZA, GANİ; Menges, Nurettin; Balcı, Metin (Elsevier BV, 2015-09-30) A concise and regioselective approach for the synthesis of 2,3-disubstituted thiophene derivatives has been developed. The synthetic strategy relies on the reaction of an in situ generated 2-mercaptoacetaldehyde with various alkynones. Furthermore, we calculated the energy gap between the HOMO and the LUMO orbitals of all compounds and observed that the introduction of a strong electron-withdrawing group decreased the HOMO-LUMO energy gap.
Divergent synthesis of polysubstituted isoxazoles, isoxazoline N-oxides, and dihydroisoxazoles by a one-pot cascade reaction Rouf, Abdul; ŞAHİN, Ertan; Tanyeli, Cihangir (Elsevier BV, 2017-01-26) An efficient one-pot synthesis of a new class of 3,4,5-trisubstituted isoxazoline N-oxides/isoxazoles and dihydroisoxazoles is developed by a green approach from aromatic and aliphatic aldehydes by controlling the reaction conditions. Aldehydes were reacted with ethyl nitroacetate in the presence of DABCO as a catalyst under ultrasonication. In aromatic aldehydes, isoxazoline N-oxides were obtained exclusively when the reaction was carried out at 40 degrees C, but raising the temperature to 80 degrees C iso...
Manganese(III) acetate based tandem oxidation of various α and β-alkoxy α,β-unsaturated ketones Tanyeli, Cihangir; Sezen, Bengü (Elsevier BV, 2002-12-09) We described the unusual results of manganese(III) acetate based tandem oxidation of various alpha and beta-alkoxy alpha,beta-unsaturated ketones to afford the corresponding alpha'-acetoxy-alpha'-phenyl substituted oxidation products in good yields. The tandem oxidation to monoacetoxylation ratio can be tuned by the amount of manganese(III) acetate.

Citation Formats

S. Okumus, C. Tanyeli, and A. S. Demir, “Asymmetric aldol addition of alpha-azido ketones to ethyl pyruvate mediated by a cinchona-based bifunctional urea catalyst,” TETRAHEDRON LETTERS, pp. 4302–4305, 2014, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47300.