Synthesis method of methylene methanedisulfonate

Abstract

The invention relates to the technical field of organic synthetic chemistry, and in particular, relates to a synthesis method of methylene methanedisulfonate. The synthesis method of methylene methanedisulfonate comprises the following steps: adding methyldisulfonic acid and dichloroethane into a reaction container, uniformly stirring, and adding phosphorus pentoxide; raising the temperature to 80-86 DEG C, adding paraformaldehyde and phosphorus pentoxide into the reaction container in batches at the same time, and carrying out reflux constant-temperature reaction for 1-3 h after feeding is completed; and after the reflux constant-temperature reaction is finished, standing for 0-3 min, pouring out supernatant liquid while the supernatant liquid is hot, cooling to room temperature, filtering the cooled supernatant, and draining to obtain white methylene methanedisulfonate. According to the synthesis method of methylene methanedisulfonate, the raw materials are easy to stir, the reactiontime is short, the reaction is sufficient, the yield is high, the technological process of the synthesis process is simple, operation is easy, subsequent treatment is simple, convenient and rapid, and the synthesis method is suitable for industrial large-scale production.

Description

technical field [0001] The invention relates to the technical field of organic synthesis chemistry, in particular to a method for synthesizing methylene disulfonate. Background technique [0002] Methylene disulfonate is a new type of electrolyte additive for lithium-ion batteries. Adding methylene disulfonate to the electrolyte of lithium-ion batteries can greatly improve the high-temperature cycle performance of lithium batteries and greatly prolong the life of lithium batteries. battery life. Especially in the power battery with lithium manganate as the positive electrode material, the addition of methylene disulfonate can well prevent the manganese melted out at high temperature from being adsorbed on the surface of the negative electrode, inhibit the increase in its impedance, and effectively improve its cycle time. characteristics, thereby greatly increasing its cycle life. [0003] At present, the synthetic method of methylene disulfonate prepared by methyl disulfon...

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Problems solved by technology

[0003] At present, the synthetic method of methylene disulfonate prepared by methyl disulfonic acid mainly contains the following several modes: (1) in the methylene disulfonate synthetic method disclosed in U.S. Patent Document US7829730B2, in a four-necked flask Adopt methyl disulfonic acid and paraformaldehyde as raw material in the medium, take phosphorus pentoxide as dehydrating agent, have produced the by-products such as viscous phosphoric acid, make stirring difficulty, reaction is insufficient, and yield is relatively low; (2) China Patent CN102344436B authorized announcement of a methylene disulfonate preparation method, including acylation reaction, cyclization reaction and separation and purification method, which uses methane disulfonic acid and paraformaldehyde as raw materials, while using chlorination Highly toxic reagents such as sulfoxide or phosphorus trichloride are used as acylating reagents, and this method needs multi-step operation, and the reaction time is long, and also can produce a large amount of highly toxic by-products; (3) the disclosed ball milling of Chinese patent application CN102464649A In the synthesis of methylene methanedisulfonate, the mixture of methanedisulfonic acid, phosphorus pentoxide and formaldehyde compound is ball-milled at 0-80°C for 10-50 minutes. This method has certain limitations on the amplification of the amount of feed (4) A kind of synthetic method of methylene disulfonate of Chinese patent CN106916138B authorized announcement, methyl disulfonic acid and paraformaldehyde and band water organic solvent benzene, toluene, 1,4-dioxane After being added to the reaction kettle, the organic solvent with water keeps the distillation and reflux cycle, and the water carried in the organic solvent is separated by a water separator during the cycle. This method also has certain limitations on the enlargement of the feeding amount.

[0004] In summary, the existing method for synthesizing methylene disulfonate from methanedisulfonic acid has deficiencies such as difficulty in reaction and stirring, the need for toxic reagents, certain limitations on the amplification of the amount of feed, and further improvement is needed.

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