The elements are listed in ways that emphasize certain relationships. There are families, periods, and groups. There are some similarities between the elements within these groupings.
The periodic table has diagonal relationships between two elements that have the same chemical properties. Carbon and phosphorus are examples.
In cases where element-element multiple bonding is present, such as diphosphorus (P 2 ) in which two phosphorus atoms are joined by a weak triple bond, the diagonal relationship between carbon and phosphorus has long been recognized.
The expectation is that the diphosphorus molecule should mimic the attributes of the hydrocarbon acetylene. Both diphosphorus and acetylene have pi-bonds, a type of covalent bond found in molecule with multiple bonding.
A coordination complex consists of a metallic ion surrounded by bound molecule or ion. hemoglobin and chlorophyll are vital to life on earth. Industrial applications use them as catalysts a lot.
Although acetylene has well-documented coordination chemistry with single transition metals, coordination complexes that feature diphosphorus bound to a single metal center have remained elusive.
Researchers at the University of California San Diego, the University of Rochester and the Ohio State University reported binding diphosphorus to a single metal center. The work is in the March 25 issue of Science.
Unlike acetylene, diphosphorus is very unstable and reactive. When created in free form, diphosphorus reacts quickly with the substances present. The nature of diphosphorus is to combine with other elements. It is difficult to study or manipulate.
Synthetic routes have been established to form complexes. The most popular method is to separate the P 4 molecule from the white phosphorus. White phosphorus was a main component in many of the bombs used in World War II.
The work presented here provides a synthetic strategy to access mononuclear complexes in laboratory settings.
The metal ion iron was used in the experiment because it provided a good coordination platform that allowed binding of small molecule in an efficient way. In binding diphosphorus to an iron ion, they were able to stitch together the two phosphorus atoms in a way that circumvented the free release of diphosphorus, providing much sought-after stability.
Wang, who is the first author on the paper and performed the synthetic work, said that it is remarkable how stable the free diphosphorus molecule becomes upon coordinating to the sterically encumbered mononuclear iron center.
Researchers used X-ray crystallography to determine the precise 3D structure of the molecule and Mossbauer spectroscopy to observe changes in the bonding interactions between the iron ion and the diphosphorus. The researchers were able to show that the iron center's properties were influenced by diphosphorus and an acetylene molecule.
If diphosphorus can exist in a form that is relatively stable and reactive, scientists will be able to attach it to something called click chemistry. Click chemistry does not describe a single reaction, but describes a way of generating substances by joining small modular units. This could lead to new areas of discovery in synthetic chemistry for the preparation of pharmaceutical compounds.
The importance of using fundamental concepts learned in first-year chemistry in guiding new discoveries is demonstrated by this work.
More information: Shuai Wang et al, Side-on coordination of diphosphorus to a mononuclear iron center, Science (2022). DOI: 10.1126/science.abn7100 Journal information: Science Citation: Unstable molecule clicks with synthetic strategy (2022, March 25) retrieved 25 March 2022 from https://phys.org/news/2022-03-unstable-molecule-clicks-synthetic-strategy.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
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