Acid-base indicator as well as preparation method and application thereof

A technology of acid-base indicator and reaction formula, which is applied in the direction of material analysis by observing the influence of chemical indicators, analysis by making materials undergo chemical reactions, triarylmethane dyes, etc., to achieve good stability, simple synthesis, color sensitive effect

Active Publication Date: 2018-03-23
SHANXI UNIV
View PDF5 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, there are certain limitations

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Acid-base indicator as well as preparation method and application thereof
  • Acid-base indicator as well as preparation method and application thereof
  • Acid-base indicator as well as preparation method and application thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] The preparation of embodiment 1 thymol phthalein

[0026] Mix 2.0mmol thymolphthalein and 2.0mmol urotropine (HMTA) into a 50ml three-neck flask, add 10ml (0.15mol) trifluoroacetic acid (TFA) under ice-bath conditions, and stir the solution for 30min before warming up to room temperature. Continue to heat the oil bath to 72°C for reflux reaction for 24h. After the reaction is stopped, excess TFA is removed by rotary evaporation. Add 50ml H 2 O, the stirred solution was heated to 60°C, filtered after 30 min, and dried to obtain a solid. The solid was further separated by column chromatography, using petroleum ether and dichloromethane at a ratio of 1:3 (v / v) as a developer, and finally dried by rotary evaporation to obtain a light yellow powder.

Embodiment 2

[0027] The preparation of embodiment 2 thymol phthalein

[0028] Mix 1.5mmol thymolphthalein and 2.0mmol urotropine (HMTA) into a 50ml three-neck flask, add 15ml (0.2mol) trifluoroacetic acid (TFA) under ice-bath conditions, and stir the solution for 30min before warming up to room temperature. Continue to heat the oil bath to 72°C for reflux reaction for 8h. After the reaction is stopped, excess TFA is removed by rotary evaporation. Add 30ml H 2 O, the stirred solution was heated to 60°C, filtered after 30 min, and dried to obtain a solid. The solid was further separated by column chromatography, using petroleum ether and dichloromethane at a ratio of 1:3 (v / v) as a developer, and finally dried by rotary evaporation to obtain a light yellow powder.

Embodiment 3

[0029] The preparation of embodiment 3 thymol phthalein

[0030] Mix 1.5mmol thymolphthalein and 1.0mmol urotropine (HMTA) into a 50ml three-neck flask, add 15ml (0.2mol) trifluoroacetic acid (TFA) under ice-bath conditions, and stir the solution for 30min before warming up to room temperature. Continue to heat the oil bath to 72° C. for reflux reaction for 12 h. After the reaction is stopped, excess TFA is removed by rotary evaporation. Add 50ml H 2 O, the stirred solution was heated to 60°C, filtered after 30 min, and dried to obtain a solid. The solid was further separated by column chromatography, using petroleum ether and dichloromethane at a ratio of 1:3 (v / v) as a developer, and finally dried by rotary evaporation to obtain a light yellow powder.

[0031] figure 1 is the color change of thymol phthalein in buffer solution at pH 1-14 (from left to right). figure 2 It is the color change diagram of thymol phthalein in pH buffer solution of 10.0, 10.2, 10.4, 10.6, 10....

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides an acid-base indicator named thymolphthalein aldehyde. A preparation method of that acid-base indicator comprises the following steps: 1) mixing 1.5-2.0 mmol of thymolphthaleinand 1.0-2.0 mmol of urotropine (HMTA) and adding the mixture to a 50ml three-neck bottle, adding 0.15-0.20 mol (10-15 ml) of trifluoroacetic acid under the ice-bath condition, stirring the solution for 30 min and then heating the solution to room temperature; 2) continuing oil bath heating to 72 DEG C for reflux reaction for 8-24 hours, stopping the reaction, and removing excess trifluoroacetic acid by rotary evaporation; 3) adding an appropriate amount of H2O, stirring the solution, heating the solution to 60 DEG C, performing filtering after 30 min, performing drying to obtain a solid, and further separating the solid by column chromatography to obtain faint yellow powder. The indicator is easy to synthesize, stable in structure and sensitive in color change, and the PH color change is in a range of 10.8-12.0.

Description

technical field [0001] The invention relates to an acid-base indicator, in particular to a phenolphthalein-based acid-base indicator and a preparation method and application thereof. Background technique [0002] Acid-base indicators are commonly used chemical reagents, among which phenolphthalein indicators are the most widely used acid-base indicators in reality. Phenolphthalein is one of the earliest acid-base indicators discovered, and thymephenolphthalein is an acid-base indicator with a structure similar to phenolphthalein. Its pH discoloration range is 9.4-10.6, and the color changes from colorless to blue, and the pH of the solution with pH greater than 10.6 cannot be distinguished. Therefore, it has certain limitations. [0003] Thymolphthalein has multiple benzene rings, and its structure can be changed through various reactions such as substitution, oxidation, and isomerization on the benzene rings, thereby expanding new properties and applications. The present...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C07D307/885G01N21/80C09B11/08
CPCC07D307/885C09B11/08G01N21/80
Inventor 丁媛媛侯玲杰孔祥宇范珍珍郭谨昌董川双少敏
Owner SHANXI UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap