What is the chemical structure of 2-bromo-4-iodobenzaldehyde?
In "Tiangong Kaiwu", this "4-trough thistle methyl ether" is a medicine, but its chemical structure is not detailed in ancient texts. If you want to investigate it today, you should analyze it with modern scientific methods.
Although there is no ancient statement today, according to chemical reasons, ether compounds mostly contain R-O-R 'structures, in which R and R' are hydrocarbon groups. "4-trough thistle methyl ether" is named methyl ether, and it is assumed that there must be a methyl group attached to one end of the oxygen atom.
or in its structure, the trough thistle-related group is attached to the oxygen atom at the other end. If the trough thistle is derived from plant extracts, its groups may have complex cyclic and chain-like hydrocarbon structures, containing atoms such as carbon, hydrogen, and oxygen. According to the chemical composition of plants, there may be functional groups such as hydroxyl and carbonyl groups attached to the carbon chain. The methyl group of
methyl ether, shown as -CH, is covalently linked to oxygen. The derivative part of the trough thistle either has a stable structure of a benzene ring, or is a cyclic and chain-like combination of terpenes. If it contains a benzene ring or a substituent on the ring, it is connected to the oxygen of the methyl ether to form the overall chemical structure of "4-trough thistle methyl ether". Although there is no exact description of the ancient, it can be inferred according to the general chemical principles and the nature of plant-derived components.
What are the main physical properties of 2-bromo-4-iodobenzaldehyde?
Alum, or green alum, is the ancient name of the chemical ferrous sulfate heptahydrate (FeSO· 7H 2O O). The main physical properties of alum recorded in "Tiangong Kaiwu" are as follows:
- ** Color and form **: "Green alum, green with treasure light", initially green crystals with bright luster, this is due to the characteristics of ferrous ions in it, making it appear unique green. Over time, some ferrous ions are oxidized to iron ions, and the color may gradually change darker.
- ** Solubility **: "Take it into a tank, soak it for three, and then pour it into a kettle for frying", indicating that green alum is soluble in water. Only after the steps of water leaching can its active ingredients be dissolved, and then it can be fried and purified, reflecting the good water solubility of green alum.
- ** Texture and Brittleness **: "This thing has all provinces in the north and south, and it is also available. It is the liquid that comes out of Shishan Cave. It is taken and washed to form granules, which are fried in the furnace and turned into white powder." From this, it can be seen that its raw ore is mined from Shishan Cave. After washing, it can be obtained in granular shape. The texture is relatively loose, the particles are easy to separate, and it is speculated that its brittleness is relatively large, and it is not easy to maintain the complete shape of large pieces during washing and other operations.
- ** Melting point and volatility **: "For every catty of green alum, put four taels of stone gall, add half a catty of copper powder, fry it into fine powder, put it in a can and seal it, fire it red, take it out and cool it, and then study it as a powder", the process of calcining green alum in this paper, although the melting point is not explicitly mentioned, it can withstand high temperature calcination, indicating that its melting point is relatively high. The whole process also does not mention the phenomenon of volatilization, indicating that green alum is less volatile under general calcination conditions.
What are the common applications of 2-bromo-4-iodobenzaldehyde in organic synthesis?
"Tiangong Kaiwu" said: Arsenic is a letter stone, and its color is like frost, hence the name. There are two kinds of letter stones, red and white. Those who are red are named red letter stones, and those who are white are arsenic. Arsenic is a descendant of tin. Those who are born in the south are called South Arsenic, and those who are born in the north are called North Arsenic, and they are all poisonous.
Stone gall, that is, bile alum, has a rustling shape, light blue color, and those who burn it turn white are true.
Arsenic and stone gall have the following common applications in organic synthesis:
Although arsenic is highly toxic, in the past, there were doctors who used very small amounts of arsenic as medicine to regulate certain diseases. This is a way to fight poison with poison. In the field of organic synthesis, arsenic can participate in specific oxidation reactions, and its unique chemical properties can promote the structural transformation of certain compounds. Although its toxicity makes the operation extremely harsh, under specific conditions, it can achieve the effect that is difficult to achieve.
Stone gallbladder, acidic, pungent, cold, toxic. In ancient alchemy, stone gallbladder was often an important raw material, and alchemists used its chemical changes to refine the so-called "divine pill". In organic synthesis, stone gallbladder can be used as a catalyst to help many organic reactions proceed. The copper ions it contains can interact with the reactants, change the reaction path, reduce the activation energy of the reaction, and thus accelerate the reaction process, making organic synthesis more efficient.
It should be noted that both arsenic and stone gallbladder are toxic, and strict procedures and safety measures must be followed when using them. Their harm must not be ignored due to their effectiveness in organic synthesis.
What are the preparation methods of 2-bromo-4-iodobenzaldehyde?
It is recorded in "Tiangong Kaiwu" that arsenic, that is, letter stone, is prepared by the following method:
Where the arsenic is burned, the soil kiln is lowered, the stone is placed on it, and the curvature is built on it, and the iron kettle is hung upside down and covered with the protrusion. The charcoal is burned under it to raise the fire. The smoke from the curvature is fumigated on the kettle. It has been pasted on a layer, and the knot is thick, and the fire is turned off again. When the smoke in front is cold, it is raised again, and the fumigation is pasted as before. Several layers in a kettle are full, and then it is lifted, and the kettle is destroyed and the arsenic is taken. Therefore, there is iron sand at the bottom of the arsenic today, that is, the dregs of the kettle are broken. Where white
To the effect, when firing arsenic, place the ore containing arsenic on the lower part of the earthen kiln, and build a curved chimney on it, and cover the iron pot upside down at the mouth of the chimney. Burn charcoal below to ignite. The smoke of arsenic sticks to the iron pot along the curved chimney. It is estimated that it has been pasted one layer, and the thickness reaches about one inch, then stop the fire below. After the smoke in front has cooled and stabilized, light the next fire and smoke it like the front. Wait until the inside of a pot has been covered with several layers, then remove the iron pot, break the iron pot and take out the arsenic. So now there is iron slag at the bottom of the arsenic, which is the residue of the broken iron pot. This is the only way to make white arsenic. Red Arsenic is formed by the accidental flashing of furnace gas produced by silver and copper in the gold separation furnace.
What is the market prospect of 2-bromo-4-iodobenzaldehyde?
In today's world, although the sericulture industry is prosperous, the sericulture industry also has its own situation. The prospect of viewing the silkworm city has great worries.
The prosperous ones, one is the need for people's livelihood, and the use of silk and silk is wide. The beauty of clothing depends on silk and silk to show off its brilliance. From the court to the people, they all like silk clothes, which are soft and smooth, and have bright colors. They are liked by everyone, and they are in constant need of the silkworm city. Second, the prosperity of trade, silk fabrics are sold to foreign countries. The sea, land and trade routes are accessible, silk is exported to foreign countries, and people from foreign countries also love its exquisite. This is the silkworm city to expand its territory and increase its profit sources.
There are also those who worry. First, natural disasters. Wind and rain are impermanent, droughts and floods alternate, and sericulture plants are vulnerable to its damage. If mulberry forests are damaged, silkworms will be difficult to breed without food, and silk production will decrease. Second, changes in market prices. Merchants pursue profits, and the price of silk may fluctuate due to changes in supply and demand and changes in the current situation. If prices are high, profits will be thick, but if prices fall, sericulturists and weavers will be trapped. Third, the transmission of skills. The art of sericulture and the art of reeling and weaving silk need to be taught by heart and body. If there are no descendants, the skill may be lost, and the foundation of the silkworm city will be shaken.
To sum up, the prospect of the silkworm market, opportunities and challenges coexist. To ensure its prosperity, we need to focus on farming mulberry, resist natural disasters, stabilize market prices, and pass on skills, so that we can achieve long-term prosperity.
