Rapid chiral analysis based on liquid-phase cyclic chemiluminescence.

Area of Science:

• Analytical Chemistry
• Organic Chemistry
• Physical Chemistry

Background:

• Chiral analysis is vital in academic and industrial research.
• Current methods for enantiomeric excess (ee) determination can be complex and time-consuming.
• Distinguishing between enantiomers, especially in challenging systems, remains an active area of research.

Purpose of the Study:

• To introduce a novel liquid-phase cyclic chemiluminescence (CCL) strategy for rapid chiral analysis.
• To demonstrate the capability of CCL for enantiomer resolution and ee determination.
• To establish CCL as a versatile tool for analyzing chiral compounds, including those difficult to differentiate by other methods.

Main Methods:

• Utilizing liquid-phase cyclic chemiluminescence (CCL) for signal acquisition.
• Measuring the concentration-independent lifetime (τ) of multistage CCL signals.
• Applying the τ values for direct ee determination of chiral mixtures without separation.

Main Results:

• CCL successfully discriminated a wide range of enantiomeric pairs (alcohols, amines, acids) using a single chiral host.
• The τ values allowed for easy differentiation of chiral systems that are challenging for NMR and fluorescence.
• Direct ee determination was achieved by a weighted average of τ values, even without pure enantiomer standards.
• The method was validated through monitoring a Walden inversion reaction and analyzing chiral drugs, showing good agreement with HPLC.

Conclusions:

• The developed CCL strategy provides an unprecedented and general protocol for chirality differentiation and ee determination.
• CCL offers a rapid, sensitive, and versatile alternative for routine ee analysis.
• This technology is anticipated to have significant applications in asymmetric synthesis and the pharmaceutical industry.