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TrimethylOrthoformate also known as the top three oxygen radicals hereinafter referred to as the original Methyl formate (Methyl orthoformate), a stimulating odour liquid is a colorless, flammable, and under the influence of water decomposition, Soluble in ethanol, ether, etc. It is an important organic synthesis intermediate, used in the synthesis of a variety of medicine, dyes and spices.
The general formula for primitive acids is RC(OH)3, and for primitive acids is RC(OR')3. The primitive acids are extremely unstable because all three hydroxyl groups are attached to one carbon atom. It has not been isolated, but the corresponding ester can exist stably.
The main purpose :
Trimethyl orthoformate is mainly used as an organic synthesis intermediate, widely used in pharmaceutical synthesis, such as the synthesis of vitamin B1, vitamin B, sulfadiazine, piroperic acid drugs, antibiotics, etc. Coatings used to prevent polyurethane or epoxy coatings due to hydration and hardening of the dehydrating agent; It can also be used in the synthesis of dyes and spices.
Manufacturing methods :
Orthoformic acid HC(OH)3 is a hypothetical compound that does not actually exist, so it is impossible to generate compounds such as trimethyl orthoformate through methyl orthoformate esterification reaction. The manufacturing technology of orthoformic acid is divided into the old method using chloroform as raw material and the new route using hydrocyanic acid as raw material. The technical route of ethyl chloroform as raw material is divided into two steps and one step. Two-step process is short, less investment, mature technology, but more waste, pollution to the environment. One-step technology is a clean production technology.
(1) Two-step technology: using chloroform and sodium methoxide as raw materials to synthesize trimethyl orthoformate. The first step is the reaction of methanol and sodium metal, or the reaction of methanol and sodium hydroxide can generate sodium methoxide. The reaction is as follows:
2CH3OH plus 2NA plus 2CH3ONA plus H2
CH3OH + NaOH - CH3ONa + H2O
The second step is the reaction of chloroform and sodium methoxide to produce trimethyl orthoformate. The reaction formula is as follows:
CHCl3 + 3 ch3ona - HC (OCH3) 3 + 3 nacl
The actual production process is carried out in the methanol solution of sodium methoxide and chloroform, the reaction is carried out at about 60℃, the pressure is 0.12~0.15MPa full reflux, the reaction product is cooled, centrifugal filtration of NaCl, distillation, cut 100~105℃ distillate, can get chloroform, the total yield of more than 97%. Purity 99.8% above trimethyl orthoformate products.
(2) one-step method technology: one-step method using chloroform, methanol, sodium hydroxide as raw materials, with tributyl benzyl ammonium chloride (PTC) as the phase transfer catalyst, that is, to achieve the transfer between solid and liquid phase, one step to generate trimethyl orthoformate, some industrial devices have adopted this technology for production.
(3) Hydrocyanic acid method: this method is to react with anhydrous methanol, hydrocyanic acid and hydrochloric acid, and then continue to react with methanol to produce trimethyl orthoformate. This method can make use of hydrocyanic acid byproducts of other products, which is the most advantageous, and has the characteristics of investment and saving. However, the process uses highly toxic hydrocyanic acid as raw material and requires refrigeration equipment, which requires higher requirements for equipment sealing and safety in the production process. The technology was adopted by Kay Fries Company in the United States to produce trimethyl orthoformate.