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AT基对阳离子与 (9-甲基-A) (((1-甲基-T) 基对阳离子对比

Dunja Radisic1, Kit H Bowen, Iwona Dabkowska

  • 1Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA.

Journal of the American Chemical Society
|April 28, 2005
PubMed
概括

阳性腺-丁基对经历了无障碍的质子转移,改变了它们的结构. 甲基化阻止了这种转移,稳定了Watson-Crick或Hoogsteen配置中的基对.

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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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π Molecular Orbitals of the Allyl Cation and Anion

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Basicity of Heterocyclic Aromatic Amines

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