Borohydride

Borohydride is a group of special chemical parts called anions.

You can find these parts in many different salts. The most important ones are lithium borohydride and sodium borohydride. These salts are very useful in the world of chemistry. They act as reducing agents in organic synthesis. This means they help change other chemicals during a reaction. Scientists find them very interesting for many different tasks.

To understand how they work, we look at their shape. The boron part has a tetrahedral structure. This means it looks like a four-sided pyramid.

The way these parts react depends on their neighbors. Some groups make the center more nucleophilic, which helps it react. This happens when electron-releasing ethyl groups are attached. Other parts, like cyano groups, make it a weaker reductant. The countercation also changes how much power the reagent has.

We can look back at when these were first found. Hermann Irving Schlesinger and Herbert C. Brown described them. They did this in the year 1940. They first made lithium borohydride from a substance called diborane. Today, scientists use different ways to make them. One current method uses trimethyl borate and sodium hydride. This shows how our knowledge of these parts has grown over time.

There are many real-world uses for these salts. Sodium borohydride is made on a huge scale. In 2002, people made about 5000 tons of it every year.

It helps turn sulfur dioxide into sodium dithionite. This is used to bleach wood pulp. It also helps make medicines like vitamin A and atropine. It even helps create many different flavors and aromas.

Borohydrides can also help us with new ideas. They have a very high hydrogen content. This makes them interesting for hydrogen storage.

Some parts can also change when they get hot. They turn into metal borides through a process called chemical vapor deposition. This is a way to make thin films. These films are very hard and strong. They can even resist wear and corrosion.