Oxidative Esterification of Internal Olefins Using Palladium Catalyst
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods struggle to produce ester compounds with an α,β-unsaturated bond from internal or cyclic olefins at high yields, as these olefins have low reactivity and often result in incomplete esterification and isomerization, leaving unreacted internal or cyclic olefins behind.
Innovation Solution
A process involving the use of a palladium catalyst, a base, and molecular oxygen in an amide-based solvent allows for the oxidative esterification of internal or cyclic olefins, effectively bonding a carboxyl group to carbon atoms with double bonds or allylic positions, thereby producing ester compounds with α,β-unsaturated bonds at higher yields.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional esterification methods are used with internal or cyclic olefins, then the reaction proceeds, but the yield of ester compound with α,β-unsaturated bond is low and unreacted olefin remains
Solution Approach 1:
The invention changes the reaction parameters by introducing molecular oxygen as an oxidant and using a specific palladium catalyst system with base catalyst. This transforms the reaction mechanism to enable efficient oxidative esterification of internal and cyclic olefins, achieving high yields and complete conversion while maintaining the α,β-unsaturated bond structure.
2Productivity
If terminal olefins are used as raw material, then esterification proceeds efficiently, but internal olefins and cyclic olefins remain unreacted when used as raw material
Solution Approach 1:
The invention develops a universal esterification method that works effectively with all types of olefins including terminal, internal, and cyclic olefins. The palladium catalyst system with molecular oxygen and base creates a versatile reaction condition that can process any olefin substrate, making the method applicable to a broad range of raw materials rather than being limited to terminal olefins only.
3Ease of manufacture
If internal olefins or cyclic olefins are used, then reactivity is low, but with conventional methods only terminal olefin esterification occurs
Solution Approach 1:
The invention introduces molecular oxygen as an intermediary oxidant that enables the reaction of unreactive internal and cyclic olefins. The oxygen activates the olefin through oxidative mechanism, allowing the palladium catalyst to facilitate esterification even with low-reactivity substrates, thereby achieving complete conversion without requiring highly reactive terminal olefins.
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
This process efficiently converts internal or cyclic olefins into α,β-unsaturated ester compounds with higher yields, utilizing a palladium catalyst and molecular oxygen in an amide-based solvent to overcome reactivity issues and isomerization, enabling the effective use of previously unreactive internal and cyclic olefins.
Implementation Method 1
reacting an internal olefin or a cyclic olefin having one carbon-carbon double bond or more at a position other than terminals of a molecule thereof with a carboxylic acid in an amide-based solvent in the presence of a palladium catalyst, a base, and molecular oxygen, thereby bonding a carboxyl group of the carboxylic acid to at least one of carbon atoms constituting the carbon-carbon double bond and carbon atoms at allylic positions of the internal olefin or the cyclic olefin
Implementation Method 2
in the presence of a palladium catalyst, a base, and molecular oxygen
Data Source
AI summary
A process for producing an unsaturated bond-containing ester compound includes reacting an internal olefin or a cyclic olefin having one carbon-carbon double bond or more at a position other than terminals of a molecule thereof (the internal olefin and the cyclic olefin may each contain a hetero atom) with a carboxylic acid in an amide-based solvent represented by a formula (1) in the presence of a palladium catalyst, a base, and molecular oxygen, to obtain an ester compound having an unsaturated bond.