Silyl-based alkyne-modifying linker for the preparation of C-terminal acetylene-derivatized protected peptides

Martin Strack1, Sina Langklotz, Julia E Bandow

  • 1Inorganic Chemistry 1, Bioinorganic Chemistry, Department of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstrasse 150, D-44780 Bochum, Germany.

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Introduction
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Preparation of Alkynes: Dehydrohalogenation

Introduction
Alkynes can be prepared by dehydrohalogenation of vicinal or geminal dihalides in the presence of a strong base like sodium amide in liquid ammonia. The reaction proceeds with the loss of two equivalents of hydrogen halide (HX) via two successive E2 elimination reactions.
Acidity of 1-Alkynes02:42

Acidity of 1-Alkynes


The acidic strength of hydrocarbons follows the order: Alkynes > Alkenes > Alkanes. The strength of an acid is commonly expressed in units of pKa — the lower the pKa, the stronger the acid. Among the hydrocarbons, terminal alkynes have lower pKa values and are, therefore, more acidic. For example, the pKa values for ethane, ethene, and acetylene are 51, 44, and 25, respectively, as shown here.
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Alkylation of β-Ketoester Enolates: Acetoacetic Ester Synthesis

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