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

2014-07-30
Okumus, Seda
Tanyeli, Cihangir
Demir, Ayhan Sıtkı
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).
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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.