thiophene-3,4-diamine

The main use of mercury-3,4-dibromide is found in "Tiangong".
Mercury is an alloy of mercury and other gold. Mercury-3,4-dibromide, which was useful in smelting in the past. In ancient smelters, mercury was often used to trap gold. Gold can be dissolved in mercury to form mercury, which is collected and then added to retain mercury and gold, and this method is effective for extracting gold.

to-3,4-dibromide, which is also useful in dyeing and other industries. In ancient dyes, if you want to get the bright color, or use this. It can be used as a medium for dyeing, and the dye is firmly attached to the material, so that the dyeing effect is better, the color is long-lasting and not easy to fade. And in some materials, mercury-3,4-dibromide may also be used in them. In ancient times, manufacturers sought the sum of properties, or used it to integrate and increase efficiency. However, due to the toxicity of mercury, the use of mercury should also be cautious.
Therefore, mercury-3,4-dibromide plays a certain role in many aspects such as ancient smelting, dyeing, and dyeing. Due to the replacement, its use method and use may have been changed, but it has an unavoidable position in the development of past technologies.

The physical properties of 5,9-diethyl-3,4-diphenyl are as follows:
This substance is crystalline at room temperature, hard and brittle, and slippery to the touch. Its color is as white as snow, pure and free of variegated colors. Viewed under light, it often shines with a faint luster, as if it has a brilliant flow.
Its melting point is quite specific, about [X] degrees Celsius. When it reaches this temperature, the solid body gradually melts and turns into a flowing liquid. This process is smooth and orderly without drastic changes. The boiling point is around [X] degrees Celsius. At this temperature, the liquid boils and rises into a gaseous state. The density of
is slightly heavier than that of ordinary things, about [X] grams per cubic centimeter. When placed in the hand, its heavy state can be felt.
Solubility is also an important characteristic. It is extremely difficult to dissolve in water, just like mutual exclusion with water, and sinks to the bottom when entering water, and does not blend with water. However, in organic solvents such as ethanol and ether, it shows good solubility, can be slowly dispersed, and finally integrates with the solvent to form a uniform solution.
Its volatility is weak, and it is placed in an open environment at room temperature for a long time, with minimal mass loss. Smell it, it has little odor, no pungent feeling, and no special fragrance. And it has a certain stability. Under common environmental conditions, it is not easy to chemically react with components in the air such as oxygen and carbon dioxide, and can be stored for a long time without deterioration.

Alas! If you want to understand the chemical properties of pentyne-3,4-diene, you should study its structure and environment in detail.
Fupentyne-3,4-diene, with the complex structure of alkynyl and dienyl groups. The alkynyl group contains carbon-carbon three bonds, and its electron cloud density is high and electron-rich, so it is easy to be attacked by electrophilic reagents. In case of hydrogen halide, it can react with electrophilic addition. The halogen atom is added to the carbon of the three bonds to form an alkenyl halide first. If the amount of hydrogen halide is sufficient, it can be added again to obtain a saturated halogenated hydrocarbon.
And its dienyl part also has unique properties. The structure of the conjugated diene gives it a conjugation effect. This conjugated system allows the electron cloud to be delocalized and the molecular stability is increased. It can participate in the Diels-Alder reaction, and synergistically react with diene-friendly bodies, such as maleic anhydride, to form a six-membered cyclic compound. This is an important reaction for building a cyclic structure.
Furthermore, the terminal alkynyl hydrogen of pentyne-3,4-diene has a certain acidity. Due to the strong electronegativity of the three-bond carbon, the electron cloud of alkynyl hydrogen is biased towards carbon, and hydrogen is easy to leave in the form of protons. Therefore, it can react with strong bases, such as sodium amide, to form alkynyl negative ions. This negative ion can be used as a nucleophilic reagent to react with electrophilic reagents such as halogenated hydrocarbons to achieve carbon chain growth.
And because of its many unsaturated bonds, oxidation reaction is also an important chemical behavior. Under the action of appropriate oxidants, such as potassium permanganate, etc., carbon-carbon unsaturated bonds can be oxidized and broken to form corresponding carboxylic acids, carbon dioxide and other products. The specific products depend on the reaction conditions.
In conclusion, pentyne-3,4-diene has the chemical properties of both alkyne and diene due to its unique structure, which can provide rich possibilities for the construction of organic compounds with diverse structures in the field of organic synthesis. It is an important object of organic chemistry research.

To prepare o-bromo-3,4-dihydroxybenzaldehyde, the synthesis method is quite complicated, and it also requires exquisite skills. Today, the ancient method is described, I hope it will help.
First, you can start from phenols. Take a suitable phenol first, and introduce an acyl group through the acylation method to obtain the acylation of the phenol. This step requires careful selection of acylating reagents and reaction conditions to accurately integrate the acylation group. Commonly used acylating agents, such as acyl halides or acid anhydrides, react with phenols in the presence of suitable catalysts. Catalysts or Lewis acids, such as aluminum trichloride, are used to help the reaction proceed smoothly.
The next step is halogenation. Bromine atoms are introduced into the acylates of phenols to obtain bromine-containing intermediates. When halogenating, halogenating reagents such as bromine or N-bromosuccinimide (NBS) are selected. Bromine is active, and the reaction needs to be controlled by temperature and amount to prevent over-halogenation; NBS is relatively mild and easier to control. The choice of halogenation position depends on the reaction conditions and substrate structure. The introduction of ortho-sites often requires specific positioning groups to guide.
Furthermore, the obtained bromine-containing intermediate product is hydrolyzed and oxidized to obtain the target product o-bromo-3,4-dihydroxybenzaldehyde. The step of hydrolysis is to break the acyl group to form a hydroxyl group. It is necessary to choose suitable hydrolysis conditions, or use acid hydrolysis, or alkali hydrolysis, depending on the characteristics of the substrate. The method of oxidation is to oxidize a specific group to an aldehyde group, such as using a mild oxidizing agent, manganese dioxide or Dess-Martin reagent, etc., to precisely oxidize without damaging other structures.
Second, there is also a method of starting from the benzene ring. First, the benzene ring is constructed from suitable raw materials through multi-step reaction, and the desired substituent is pre-distributed on the ring, and then bromine atoms, aldehyde groups and hydroxyl groups are introduced in turn. Although this approach is complicated to start, the position and order of the substituents can be precisely controlled. For example, starting with a derivative of benzene, through electrophilic substitution reaction, the required groups are introduced one after another, and then the functional group is converted to obtain o-bromo-3,4-dihydroxybenzaldehyde. Each step of the reaction requires fine regulation of the reaction conditions, such as temperature, solvent, catalyst, etc., to ensure that the reaction proceeds in the expected direction and a high-purity product is obtained.

I look at the market, and the price of the product often varies according to the time, place, and quality. As for the price of the medicine "cilantro-3,4-diol", it is difficult to determine.
The market is bustling, with profits coming and going, and the price fluctuates like clouds. The price of this product may vary due to the difficulty of picking, the need for usage, and the change of time.
If this product is produced in a remote place, it is difficult to harvest, its transportation is difficult, or the method of processing is complicated, and it needs to be refined and refined, then its price will be high. Or when the epidemic is rampant, doctors rely on this medicine to cure diseases, and those who need it will also increase in price.
On the contrary, if the origin is widely distributed, the procurement and transportation are convenient, and there are few users, the price should be cheap.
However, there is no detailed information, so it is difficult to determine the range of its price. Although I want to tell you a fixed number, I can't. Only by visiting the merchants of various medicine shops and observing the supply and demand at all times can I get its approximate price.