Scalable Chroman Synthesis Without Pyrophoric Reagents
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for synthesizing 2-methyl-5-((2R,4S)-2-((((R)-1-(naphthalen-1-yl)ethyl)amino)methyl)chroman-4-yl)benzoic acid and its derivatives involve the use of pyrophoric reagents and complex chromatography, making them hazardous and unsuitable for large-scale production, and result in the formation of unwanted impurities.
Innovation Solution
A synthesis process that avoids pyrophoric reagents and chromatography by using mild reducing agents like sodium bis(2-methoxyethoxy)aluminium hydride and ammonium formate, and employs recrystallization techniques to achieve high purity, enabling industrial-scale production with less than 0.2% impurity levels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If pyrophoric reagents are used for synthesis, then reaction efficiency is improved, but safety hazards increase and infrastructure costs increase
Solution Approach 1:
The patent replaces pyrophoric reagents with inexpensive, non-pyrophoric reducing agents such as sodium borohydride and aluminum isopropoxide. These reagents are safer, do not require specialized infrastructure, and can be handled under normal laboratory conditions, thereby eliminating safety hazards while maintaining reaction efficiency
Solution Approach 2:
The patent changes the chemical parameters of the reducing agents from pyrophoric to non-pyrophoric substances. This parameter change allows the reaction to proceed efficiently without the need for specialized safety infrastructure, thus resolving the contradiction between productivity and safety
2Manufacturing precision
If chromatography purification is used, then compound purity is improved, but process complexity and costs increase
Solution Approach 1:
The patent extracts and eliminates the chromatography purification step from the synthesis process. Instead, it employs simple filtration and recrystallization techniques that achieve the required purity levels without the complexity and costs associated with chromatography, thus resolving the contradiction between manufacturing precision and device complexity
Solution Approach 2:
The patent replaces expensive, complex chromatography systems with simple, inexpensive filtration and recrystallization procedures. These simpler methods achieve comparable purity results without requiring sophisticated equipment or extensive operational complexity
3Speed
If harsh hydrogenation conditions are used, then reaction speed is improved, but unwanted impurities increase
Solution Approach 1:
The patent changes the reaction conditions from harsh hydrogenation to milder reducing conditions using reagents like sodium borohydride and aluminum isopropoxide. These milder conditions maintain adequate reaction speed while significantly reducing the formation of unwanted impurities, thereby resolving the contradiction between speed and manufacturing precision
Solution Approach 2:
The patent introduces mild reducing agents as intermediaries that facilitate the reduction reaction without causing the side reactions and impurity formation associated with harsh hydrogenation conditions. These intermediary reagents enable controlled reaction progression with minimal impurity generation
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 process achieves high-purity compounds suitable for industrial-scale production without hazardous reagents, reducing infrastructure costs and impurity levels, while eliminating the need for exogenous hydrogen gas, thus enhancing safety and efficiency.
Implementation Method 1
reducing the amide group of compound-5 using sodium bis(2-methoxyethoxy)aluminium hydride in toluene to give compound-6
Implementation Method 2
reducing compound-1 using Pd/C and ammonium formate to give compound-2
Implementation Method 3
reducing compound-1 using Pd/C and ammonium formate to give compound-2
Implementation Method 4
employs recrystallization techniques to achieve high purity
Data Source
AI summary
A process for manufacturing substituted chroman compounds in an economically scalable manner, without the use of pyrophoric reagents. Also disclosed herein are chroman compound synthesis routes that do not include column chromatography purification steps. The disclosure also relates to the intermediates used in the synthesis. In particular, the disclosure relates to the synthesis of the Calcium sensing receptor (CaSR) modulating agent 2-methyl-5-((2R,4S)-2-((((R)-1-(naphthalen-1-yl)ethyl)amino)methyl)chroman-4-yl)benzoic acid, its intermediates and pharmaceutically acceptable salts thereof.