CN-114524783-B - Methods for synthesizing N-methylpiperazine diphenol amides and related compositions

Abstract

Methods for synthesizing N-methylpiperazine diphenol amides are provided. The method includes contacting a diphenolic acid with N-methylpiperazine to form a reaction mixture, and heating the reaction mixture to form a reaction product comprising N-methylpiperazine diphenol amide. Related compositions are also provided.

Inventors

• P.J. McCrowski
• J.L.Li
• P. E. Hausen
• H.ZHOU

Assignees

• 思拓凡瑞典有限公司

Dates

Publication Date

20260508

Application Date

20150529

Priority Date

20140612

Claims (6)

1. 1. A method for synthesizing N-methylpiperazine diphenol amide comprising: and heating the reaction mixture at a temperature in the range of 140 ℃ to 180 ℃ for a duration in the range of 8 hours to 40 hours to form a reaction product comprising N-methylpiperazine diphenol amide, wherein the N-methylpiperazine diphenol amide has a purity of greater than 98%, wherein the molar ratio of N-methylpiperazine to diphenol acid is in the range of 3 to 4.
2. 2. The process of claim 1, comprising heating the reaction mixture at a temperature in the range of 160 ℃ to 180 ℃ for a duration in the range of 16 hours to 24 hours.
3. 3. The process of claim 1, further comprising separating N-methylpiperazine diphenol amide from the reaction product by crystallization.
4. 4. The method of claim 1, wherein the reaction product is free of diphenolic acid methyl ester.
5. 5. The process of claim 1, wherein the yield of N-methylpiperazine diphenol amide relative to diphenolic acid is greater than 80%.
6. 6. A method for synthesizing N-methylpiperazine diphenol amide comprising: contacting diphenolic acid with N-methylpiperazine in the absence of solvent to form a reaction mixture, and Heating the reaction mixture at a temperature in the range of 160 ℃ to 180 ℃ for a duration in the range of 16 hours to 24 hours to form a reaction product comprising N-methylpiperazine diphenol amide, Wherein the molar ratio of N-methylpiperazine to diphenolic acid is in the range of 3-4.

Description

Methods for synthesizing N-methylpiperazine diphenol amides and related compositions Background The present invention relates generally to a process for the synthesis of N-methylpiperazine diphenol amide. More particularly, the present invention relates to a method for the one-step synthesis of N-methylpiperazine diphenol amide and related compositions. A typical method for synthesizing N-methylpiperazine diphenol amide comprises a two-step reaction comprising converting diphenolic acid into diphenolic acid methyl ester, followed by reacting the ester with N-methylpiperazine. However, this method generally requires the addition of a solvent, which necessitates an additional step of solvent removal. In addition, the two-step process requires two separate steps to isolate and purify the reaction products (diphenolic acid methyl ester and N-methylpiperazine diphenol amide). Thus, typical two-step processes may not provide the desired efficiency (yield) and may not be cost effective. Thus, there is a need for a cost-effective and efficient method for synthesizing N-methylpiperazine diphenol amide. In addition, there is a need for a one-step process for the synthesis of N-methylpiperazine diphenol amide. Summary of The Invention Embodiments of the present invention are included to meet these and other needs. One embodiment is a process for the synthesis of N-methylpiperazine diphenol amide. The method includes contacting a diphenolic acid with N-methylpiperazine to form a reaction mixture, and heating the reaction mixture to form a reaction product comprising N-methylpiperazine diphenol amide. One embodiment is a process for the synthesis of N-methylpiperazine diphenol amide. The method comprises contacting a diphenolic acid with N-methylpiperazine under substantially solvent-free conditions to form a reaction mixture. The method further comprises heating the reaction mixture at a temperature in the range of about 160 ℃ to about 180 ℃ for a duration in the range of about 16 hours to about 40 hours to form a reaction product comprising N-methylpiperazine diphenol amide. One embodiment is a composition comprising N-methylpiperazine diphenol amide. The composition is formed by contacting a diphenol acid with N-methylpiperazine to form a reaction mixture, and heating the reaction mixture to form a reaction product comprising N-methylpiperazine diphenol amide. Detailed description of the preferred embodiments Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could vary with a permissible limit without resulting in a change in the basic function to which it is related. Accordingly, a value modified by one or more terms, such as "about" and "substantially," are not to be limited to the precise value specified. In some cases, the approximating language may correspond to the precision of an instrument for measuring the value. Unless the context or language indicates otherwise, range limitations may be combined and/or interchanged herein and throughout the specification and claims, such ranges are identified and include all the sub-ranges contained therein. In the following description and claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. The term "or" as used herein does not mean exclusive and refers to the presence of at least one of the recited components and includes situations in which a combination of the recited components may be present, unless the context clearly indicates otherwise. Methods for synthesizing N-methylpiperazine diphenol amides are provided. In particular, a one-step process for the synthesis of N-methylpiperazine diphenol amide is provided. The term "one-step process" as used herein means the direct conversion of diphenolic acid to N-methylpiperazine diphenol amide without an additional intermediate step of forming an ester, as shown in scheme 1:。 this is in contrast to the "two-step process" described in U.S. patent No. 7985339, assigned to GENERAL ELECTRIC Company. The method includes contacting a diphenolic acid with N-methylpiperazine to form a reaction mixture. In some embodiments, the molar ratio of N-methylpiperazine to diphenolic acid is in the range of about 1.5 to about 5. In some embodiments, the molar ratio of N-methylpiperazine to diphenolic acid is in the range of about 3 to about 5. In certain embodiments, the molar ratio of N-methylpiperazine to diphenolic acid is in the range of about 3 to about 4. In some embodiments, the diphenolic acid is contacted with the N-methylpiperazine under conditions substantially free of solvents. The term "substantially solvent-free conditions" as used herein means that the amount of solvent added during the step of contacting the diphenolic acid with the N-methylpiperazine is less than about 10% by weight of the total reaction mixture. In certain embodiments, the reaction mixture is formed