Benzene, 2,3-Difluoro-1-Iodo-4-Methyl-

The main use of this product, 2,3-diene-1-alkyne-4-methylnaphthalene, is not explicitly mentioned in "Tiangong Kaiwu", but it can be inferred from the relevant process and material use.
In ancient chemical processes, many substances have specific uses due to their unique chemical properties. This compound contains diene, alkyne and naphthalene structures, or plays a role in ancient dyeing processes. Ancient dyeing often relied on natural and synthetic dyes. This compound has a complex structure and can be converted into dye intermediates through specific treatment to add color to fabrics. Its unique unsaturated bonds may participate in chemical reactions, helping to produce brightly colored and firm dyes.
Furthermore, the production of ancient spices may also be related to it. Complex organic structures often have a special smell. This compound can be extracted, prepared, or can be used as a fragrance component. In incense, making sachets, etc., it adds aroma to life.
In addition, in the field of ancient medicine, although there is no exact record, the ancient people have continued to explore the medicinal uses of natural substances. Some organic compounds with specific structures may have pharmacological activities. This compound may have been tried for the treatment of certain diseases or to relieve symptoms. However, due to technical and cognitive limitations, its medicinal effect and safety have not been deeply studied.
Although "Tiangong Kaiwu" does not specifically describe the use of this product, it is speculated from the common requirements of ancient crafts and material structure characteristics, or it may be used in dyeing, fragrances, medicine, etc.

Abamectin is a good medicine for repelling insects, and it has great functions in farming and mulberry animal husbandry. Its physical properties have their own unique characteristics.
Looking at its shape, under room temperature, it is mostly in the shape of white to light yellow crystalline powder. It is delicate and uniform, and the texture is soft to touch, like fine sand, but it has the characteristics of crystals. It is slightly shiny under light, like a faint star, shining with agility.
When it comes to odor, methylaminobamectin has a slight odor, a fine smell, and a slight but not greasy taste. It is not pungent or rich. If it is absent, it does not disturb people's sense of smell. When used, it will not cause discomfort due to strong odor.
Besides its solubility, this substance has different performance in organic solvents. In solvents such as acetone, methanol, and acetonitrile, it has a certain solubility and can be fused with it, just like water emulsion, evenly dispersed. However, the solubility of water is relatively weak, and it is difficult to dissolve in water, just like the difficulty of oil and water, it is suspended or precipitated after entering water. This characteristic also determines that in practical application, it needs to be dispersed by organic solvents in order to be more effective.
Its melting point is also one of the important physical properties. The melting point of aminoabamectin is relatively high, and it needs a specific temperature to make it from solid to liquid. This characteristic makes it possible to maintain a stable solid state in ordinary environments, making it easy to store and transport, and it is not easy to change its shape due to temperature fluctuations, ensuring the stability of its quality.
And the density of aminoabamectin is moderate, neither frivolous nor heavy and difficult to move. The moderate density makes it easier to accurately control the dosage when formulating and applying the preparation, and to exert the best effect. It is very convenient in agricultural operations.

Among the many knowledge involved in "Tiangong Kaiji", it is necessary to discuss the chemical stability of methyl ethers in detail.
Substances such as methyl ethers have certain characteristics of intramolecular carbon-oxygen bonding in terms of their structure. In common chemical environments, methyl ethers exhibit a relatively stable state. This stability comes from their chemical bond energy distribution. The carbon-oxygen single bond has a certain strength, and the presence of methyl groups protects the ether bond in terms of steric resistance.
Under general chemical reaction conditions, methyl ethers are difficult to decompose or transform spontaneously. For example, at room temperature and without specific catalysts, strong oxidants, etc., it can maintain its own structural integrity. In many organic reaction systems, methyl ether often exists as a relatively stable structural unit. When participating in the reaction, it mostly changes other active groups under specific conditions, while its own ether bond is relatively stable.
However, it should be understood that methyl ether is not absolutely stable. When faced with extreme chemical conditions such as high temperature, strong acidity, and strong alkalinity, its stability will be challenged. In a strong acid environment, protons may bind to the oxygen atom of the ether bond, thereby weakening the carbon-oxygen bond, which in turn triggers the break of the ether bond and the hydrolysis of the ether. Similarly, under the action of strong bases and some specific reagents, methyl ether may also undergo specific conversion reactions. In general, the chemical properties of methyl ether are stable under normal chemical environments and general reaction conditions, but under extreme or special chemical conditions, its stability will be broken and corresponding chemical changes will occur.

There are many methods for the synthesis of 2-methyl-3-butyne-1-alcohol, which are described in ancient methods to help.
First, acetylene and acetone can be used as starting materials. Under appropriate conditions, acetylene reacts with alkali metals to form acetylene metal salts, which have strong nucleophilicity. The carbonyl carbon in acetone is electrophilic, and when the two meet, the acetylene metal salt performs nucleophilic addition to the carbonyl group of acetone to obtain an intermediate containing the structure of acetylene alcohol. After appropriate reduction steps, some functional groups of the addition product can be adjusted to the structure of the target product 2-methyl-3-butyne-1-alcohol. In this process, suitable reducing agents and reaction conditions are required to obtain products with higher yield and purity.
Second, propargyne and formaldehyde are used as raw materials. The acetylene bond of propargyne has a certain reactivity, and under the action of a specific catalyst, a nucleophilic addition reaction occurs with formaldehyde. Due to the high electron cloud density on the acetylene bond, it attacks the carbonyl carbon of formaldehyde, forming a new carbon-carbon bond, resulting in an intermediate containing hydroxyl and alkynyl groups. After reasonable reaction steps, such as protection and deprotection of some groups, functional group conversion, etc., the intermediate can be gradually converted into 2-methyl-3-butyne-1-ol. This route requires strict control of the reaction conditions of each step to ensure that the reaction proceeds in the expected direction.
Third, the reaction of halogenated hydrocarbons and alkynides can be used. First prepare suitable halogenated hydrocarbons, such as halogenated hydrocarbons containing methyl groups and halogenated atoms, and at the same time prepare sodium alkynide and other alkynides. The halogen atom of the halogenated hydrocarbon has good departure property, and the alkynyl anion of the alkynide is a strong nucleophilic reagent. The nucleophilic substitution reaction occurs between the two to form a carbon-carbon bond, and the carbon skeleton of the target product is constructed. Subsequent conversion of appropriate functional groups, such as the introduction of hydroxyl groups, finally obtains 2-methyl-3-butyne-1-ol. This method requires high purity and reaction conditions of the halogenated hydrocarbon and the alkynide to ensure the smooth progress of the reaction and the quality of the product.

Sad husband! The precautions related to aminonaphthalene during storage and transportation are really urgent and must not be ignored.
The first to bear the brunt, aminonaphthalene is toxic, and during storage and transportation, it is necessary to beware of its leakage, which can cause poisoning to people and the environment. Therefore, the storage place should be selected in a cool and ventilated warehouse, away from fire and heat sources, and must be separated from oxidants, acids, and edible chemicals. Do not mix storage.
Furthermore, the packaging should not be ignored. The packaging must be tightly sealed to ensure that there is no risk of leakage. During transportation, vehicles should be equipped with corresponding varieties and quantities of fire equipment and leakage emergency treatment equipment. Summer transportation should be carried out in the morning and evening to avoid high temperature periods to prevent aminonaphthalene from being unstable due to excessive temperature.
The loading and unloading during transportation should also be handled with caution. It should be handled lightly, and should not be dropped or pressed heavily to avoid damage to the packaging. In the unfortunate event of a leak, emergency personnel must wear a full mask and protective clothing. Quickly evacuate the personnel in the leaked contaminated area to a safe area, prohibit unrelated personnel from entering, and cut off the fire source. In the case of a small amount of leakage, absorb it with sand, vermiculite or other inert materials; in the case of a large amount of leakage, build a dike or dig a pit for containment, transfer it to a tanker or a special collector with a pump, and recycle it or transport it to a waste treatment site for disposal.
In summary, during the storage and transportation of aminonaphthalene, it is necessary to adhere to strict regulations and operate cautiously to ensure safety.