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An examination of several catalytic reactions among the group 15 elements is presented. The connections between the chemistry of the pnictogens can sometimes be challenging, but aspects of metal–pnictogen reactivity are the key. The connecting reactivity comes from metal-catalyzed transformations such as dehydrocoupling and hydrofunctionalization. Pivotal mechanistic insights from E–N heterodehydrocoupling have informed the development of highly active catalysts for these reactions. Metal–amido nucleophilicity is often at the core of this reactivity, which diverges from phosphine and arsine dehydrocoupling. Nucleophilicity connects to the earliest understanding of hydrophosphination catalysis, but more recent catalysts are leveraging enhanced insertion activity through photolysis. This photocatalysis extends to hydroarsination, which may also have more metal–arsenido nucleophilicity than anticipated. However, metal-catalyzed arsinidene chemistry foreshadowed related phosphinidene chemistry by years. This examination shows the potential for greater influence of individual discoveries and understanding to leverage new advances between these elements, and it also suggests that the chemistry of heavier elements may have more influence on what is possible with lighter elements.
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This content will become publicly available on December 27, 2025
Dehydrocoupling: A General Route to Bonds Between P-Block Elements
Dehydrocoupling is a unique reaction to p-block elements that allows for the formation of bonds between these main group elements with loss of hydrogen. The transformation is highly atom economical, and hydrogen is a relatively benign byproduct that also provides the thermodynamic driving force for the reaction. For these reactions, couplings between most of the p-block elements are known. In the instance when bonds between the same elements are formed, then this reaction primarily applies to elements in the third period (3p) and heavier. For reactions between different elements, most any combination of p-block elements is possible. These reactions are known to make small molecules and polymers. Catalysts for this reaction include metal compounds (i.e., organometallic catalysts), Lewis acids, and frustrated Lewis pairs, and the mechanisms of dehydrocoupling are highly varied, representing much of the spectrum of catalysis.
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- Award ID(s):
- 2348198
- PAR ID:
- 10596135
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- The Chemical educator
- ISSN:
- 1430-4171
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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