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In organic chemistry, the Arndt–Eistert reaction is the conversion of a carboxylic acid to its homologue. It is named for the German chemists Fritz Arndt (1885–1969) and Bernd Eistert (1902–1978). The method entails treating an acid chlorides with diazomethane. It is a popular method of producing β-amino acids from α-amino acids. [1]
Hydrothermal synthesis can be defined as a method of synthesis of single crystals that depends on the solubility of minerals in hot water under high pressure. The crystal growth is performed in an apparatus consisting of a steel pressure vessel called an autoclave, in which a nutrient is supplied along with water. A temperature gradient is ...
The total number of radicals delivered to the system by the initiator during the course of the polymerization is low compared to the number of RAFT agent molecules, meaning that the R group initiated polymer chains from the re-initiation step form the majority of the chains in the system, rather than initiator fragment bearing chains formed in ...
The classic example of a dehydration reaction is the Fischer esterification, which involves treating a carboxylic acid with an alcohol to give an ester RCO 2 H + R′OH ⇌ RCO 2 R′ + H 2 O. Often such reactions require the presence of a dehydrating agent, i.e. a substance that reacts with water.
Alkoxides are ideal chemical precursors for sol–gel synthesis because they react readily with water. The reaction is called hydrolysis, because a hydroxyl ion becomes attached to the silicon atom as follows: Si(OR) 4 + H 2 O → HO−Si(OR) 3 + R−OH. Depending on the amount of water and catalyst present, hydrolysis may proceed to completion ...
Toxic heavy metals are often present in surface water as a result of natural processes, such as the weathering of metal-containing rocks, or due to human activity, such as mining and smelting. [2] Only the ionic forms of most metals are soluble in water. These ionic forms have a high chemical affinity for the surfaces of most sediment particles ...
The development scale can be small (ml/hour) for idea verification using a chip system and in the range of a couple of liters per hour for scalable systems like the flow miniplant technology. Chip systems are mainly used for a liquid-liquid application while flow miniplant systems can deal with solids or viscous material.
Referring to achievements that have been recognized in textbooks, cryptands enabled the synthesis of the alkalides and electrides. For example, addition of 2,2,2-cryptand to a solution of sodium in ammonia affords the salt [Na(2,2,2-crypt)] + e − , isolated a blue-black paramagnetic solid.