Overview
Ethers can also be prepared from alkenes through acid-catalyzed addition of alcohols and alkoxymercuration–demercuration.
Preparation of Ethers by Acid-Catalyzed Addition of Alcohol to Alkenes
The acid-catalyzed addition of alcohol to an alkene involves treating the alkene with an excess of alcohol in the presence of an acid catalyst to form an ether under suitable conditions. The hydrogen will add to the less substituted carbon so that the nucleophile can attack the more...

In 1931, physicist Ernst Ruska—building on the idea that magnetic fields can direct an electron beam just as lenses can direct a beam of light in an optical microscope—developed the first prototype of the electron microscope. This development led to the development of the field of electron microscopy. In the transmission electron microscope (TEM), electrons are produced by a hot tungsten element and accelerated by a potential difference in an electron gun, which gives them up to 400...

Elimination reactions of alkyl halides can yield one or more alkenes depending on the specific regiochemical and stereochemical considerations. While the regiochemistry of the reaction governs the location of the double bond in the product, the stereochemical requirements often influence the geometry.
When a substrate with two different β hydrogens undergoes an E2 elimination, the presence of a strong base can yield two regioisomeric alkenes. The more-substituted alkene is the major...

The synthesis of phenol from benzene via cumene and cumene hydroperoxide is called the Hock process. First, a Friedel–Crafts alkylation reaction of benzene with propene gives cumene. Then cumene forms cumene hydroperoxide via a radical chain reaction. In the chain initiation step, the benzylic hydrogen is abstracted to give a benzylic radical. In the chain propagation step, the benzylic radical reacts with an oxygen diradical to form a cumene hydroperoxide radical. The cumene...

The Barium Swallow Study, or a Barium Esophagogram, is a diagnostic imaging method used to visualize the upper gastrointestinal (GI) tract, including the esophagus, stomach, and small intestine. It employs barium sulfate, a radiopaque contrast material, to provide clear images of the upper digestive system, helping to identify abnormalities, diseases, or structural issues.
Purpose and Procedure
Patients undergoing this procedure ingest a liquid containing barium sulfate with a chalky...

The esophagus, a muscular conduit linking the pharynx and stomach, measures roughly 10 inches (25.4 cm) and sits behind the trachea. It remains collapsed when not swallowing. The esophagus follows a predominantly straight path through the thoracic mediastinum and enters the abdominal cavity through a diaphragmatic opening known as the esophageal hiatus.
The movement of edibles from the pharynx into the esophagus is facilitated by the upper esophageal sphincter, which is formed primarily by the...