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Updated: Jan 31, 2026

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Published on: May 4, 2018
Asymmetric and Geometry-Selective α-Alkenylation of α-Amino Acids
Hossay Abas1, Josep Mas-Roselló1, Mostafa Mahmoud Amer1
1School of Chemistry, Cantock's Close, Bristol, BS8 1TS, UK.
Abstract:
Both E- and Z-N'-alkenyl urea derivatives of imidazolidinones may be formed selectively from enantiopure α-amino acids. Generation of their enolate derivatives in the presence of K+ and [18]crown-6 induces intramolecular migration of the alkenyl group from N' to Cα with retention of double bond geometry. DFT calculations indicate a partially concerted substitution mechanism. Hydrolysis of the enantiopure products under acid conditions reveals quaternary α-alkenyl amino acids with stereodivergent control of both absolute configuration and double bond geometry.
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