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Updated: Jun 7, 2025

Preparation and Use of Carbonyl-decorated Carbenes in the Activation of White Phosphorus
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超越三重键:通过量身定制的超基素解锁二激活

Vilakkathala U Krishnapriya1,2, Cherumuttathu H Suresh2,3

  • 1Chemical Science and Technology Division, CSIR-National Institute of Interdisciplinary Science and Technology, Thiruvananthapuram - 695019, Kerala, India.

Dalton transactions (Cambridge, England : 2003)
|November 12, 2024
PubMed
概括

超基氨酸对无金属二 (N2) 激活具有前景. 理论研究表明,这些化合物可以促进N2转化为氨酸 (H2NNH2),提供可持续的固定途径.

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Preparation of 1° Amines: Gabriel Synthesis

Direct alkylation is not a suitable method for synthesizing amines because it produces polyalkylated products. Gabriel synthesis is the most preferred method to exclusively make primary amines. The method uses phthalimide, which contains a protected form of nitrogen that participates in alkylation only once to predominantly give primary amines.
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Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.
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All meta-directing substituents are deactivating groups. These substituents withdraw electrons from the aromatic ring, making the ring less reactive toward electrophilic substitution. For example, the nitration of nitrobenzene is 100,000 times slower than that of benzene because of the deactivating effect of the nitro group. The first step in an electrophilic aromatic substitution is the addition of an electrophile to form a resonance-stabilized carbocation. The energy diagrams for...
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