Tebuconazole Crystal Form 2 Solubility Stability
Solution Overview
Problem
Existing tebuconazole crystal forms have low solubility and stability under high temperature, high humidity, and light conditions, limiting their application and requiring the development of a polymorph with improved properties for use as a systemic fungicide.
Innovation Solution
A new crystal form (crystal form 2) of tebuconazole with specific X-ray powder diffraction patterns and thermal stability, characterized by high purity and non-hygroscopicity, is developed through a simple preparation method suitable for large-scale production, which includes crystallization using solvents like methylcyclohexane and activated carbon, and is formulated into a pesticide composition for effective disease control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If crystal form 1 is prepared according to the original compound patent DE 3733755, then the compound can be produced, but the solubility is low
Solution Approach 1:
The patent applies parameter changes by modifying the crystallization conditions, specifically using a mixed solvent system (first solvent and second solvent) with different polarity characteristics. This changes the physical-chemical parameters of the crystallization process, resulting in crystal form 2 which has both improved solubility and maintained stability compared to crystal form 1
Solution Approach 2:
The patent employs composite materials principle by creating a polymorph (crystal form 2) with composite crystal structure that combines the advantages of both high solubility and high stability. The new crystal form represents a composite state of the molecule in a specific spatial arrangement that optimizes both solubility and stability properties
2Quantity of substance
If a new polymorph with high solubility is developed, then the solubility is improved, but the preparation method complexity increases
Solution Approach 1:
The patent extracts the key critical parameter for obtaining crystal form 2, which is the use of a mixed solvent system comprising a first solvent and a second solvent in specific volume ratios. By identifying and extracting this essential element, the complex crystallization process is simplified into a controllable procedure with defined parameters
Solution Approach 2:
The patent simplifies the preparation method by establishing specific parameter ranges: volume ratio of first to second solvent (1:4 to 4:1), temperature range (20-80°C), and pH range (2-10). These defined parameters transform a potentially complex process into a straightforward, reproducible procedure
3Quantity of substance
If the crystal form is optimized for solubility, then the solubility increases, but the stability under high temperature, high humidity and light conditions may deteriorate
Solution Approach 1:
The patent creates crystal form 2 as a composite polymorph that integrates both high solubility and high stability properties into a single crystal structure. This composite crystal form achieves the dual objective of improved solubility while maintaining excellent stability under high temperature, high humidity, and light conditions
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The new crystal form 2 exhibits superior solubility, stability, and biological activity, making it suitable for preventing and controlling plant diseases, and is easier to process into water-dispersible granules with improved disintegration performance.
Implementation Method 1
a method for preparing the crystal, which comprises the steps of: (a) providing a solution of the compound of formula I in a first solvent; and (b) crystallizing above solution to form the crystal according to the first aspect of the present invention, which is crystal form 2
Implementation Method 2
the X-ray powder diffraction pattern of which includes 3 or more 2θ values selected from the group consisting of 17.1±0.2°, 17.4±0.2°, 20.7±0.2°, 24.3±0.2°, 26.7±0.2°, and 27.5±0.2°
Data Source
AI summary
A tebuconazole polymorph and a preparation method therefor are described. In particular, a polymorph of (RS)-1-(4-chloropheny)-4,4-dimethyl-3-(1H-1,2,4-triazol-1-ylmethyl) pentan-3-ol, a preparation method therefor and use thereof are provided. The tebuconazole polymorph has a high purity and excellent crystallization properties, is stable under high humidity, high temperature and light conditions, has excellent solubility, and has high processing properties for formulations, high biological activities and good sterilization effects. The preparation method is simple, has stable processes, and can be implemented on a large scale. The polymorph can greatly improve the quality control and industrial application of tebuconazole-containing pesticides.