Cyclic β-hydroxy-α-nitrosulfone isomers readily interconvert via open-chain aldehyde forms.

Area of Science:

• Organic Chemistry
• Supramolecular Chemistry
• Stereochemistry

Background:

• Cyclic β-hydroxy-α-nitrosulfones represent a class of compounds with potential for diverse chemical transformations.
• Understanding their isomerization mechanisms is crucial for synthetic applications and predicting their stability.

Purpose of the Study:

• To synthesize structurally diverse cyclic β-hydroxy-α-nitrosulfones.
• To investigate the isomerisation reactions and mechanisms of these compounds.
• To elucidate the role of open-chain aldehyde forms in the isomer interconversion.

Main Methods:

• Michael condensation reactions followed by cyclisation.
• Purification techniques including chromatography and recrystallization.
• Spectroscopic analysis (NMR, X-ray crystallography) for structural elucidation.
• Investigation of isomerisation under various conditions (silica gel, basic/neutral solutions, different solvents).

Main Results:

• Synthesis of two distinct cyclic β-hydroxy-α-nitrosulfones.
• Demonstration of facile isomer equilibration via open-chain aldehyde intermediates under mild conditions.
• Identification of multiple diastereomers and constitutional isomers, including cyclic hemiacetals.
• Observation of solvent-dependent isomerisation and base-catalyzed ring-opening/dehydration.

Conclusions:

• Cyclic β-hydroxy-α-nitrosulfones are conformationally flexible and prone to isomerisation.
• Open-chain aldehyde forms are key intermediates in the interconversion of cyclic isomers.
• The study provides insights into the reactivity and stability of nitrosulfone derivatives.