CAS No. 29943-42-8: Exploring Tetrahydro-4H-Pyran-4-One — Structure, Properties, and Applications

Tetrahydro-4H-pyran-4-one (CAS No. 29943-42-8) is an important organic compound used in synthetic chemistry, flavor chemistry, fragrance formulation, and pharmaceutical research. Owing to its reactive functional groups and stable ring structure, it serves as a versatile intermediate in numerous chemical pathways.

This blog provides a clear overview of its characteristics, synthesis relevance, and key applications.

What Is Tetrahydro-4H-Pyran-4-One?

Tetrahydro-4H-pyran-4-one is a six-membered heterocyclic compound composed of five carbon atoms and one oxygen atom. Structurally, it is a partially saturated pyran derivative with a ketone group at the 4-position, giving it distinctive chemical reactivity.

Basic Chemical Information

• CAS Number: 29943-42-8
  
  

• Molecular Formula: C₅H₈O₂
  
  

• Molecular Weight: 100.12 g/mol
  
  

• Chemical Class: Heterocyclic ketones / oxygen-containing cyclic compounds
  
  

Physical & Chemical Properties

Tetrahydro-4H-pyran-4-one exhibits properties typical of small cyclic ketones, making it useful in controlled organic transformations.

Key Properties

• Appearance: Clear to pale yellow liquid
  
  

• Odor: Mild, sweet, sometimes described as caramel-like
  
  

• Solubility: Miscible with most organic solvents; moderately soluble in water
  
  

• Boiling Point: Typically around 170–175 °C
  
  

• Reactivity:
  
  

• Ketone group allows nucleophilic addition reactions
  
  

• Ring structure supports hydrogenation, reduction, and acetal formation
  
  

• Can act as a building block in multi-step organic synthesis
  
  

These properties contribute to its value as an intermediate compound.

How It Is Used in Chemistry

1. Intermediate in Organic Synthesis

Tetrahydro-4H-pyran-4-one acts as a precursor to various oxygenated heterocycles, protective groups, and functionalized pyran derivatives. Its reactivity makes it important in the synthesis of:

• natural product analogs
  
  

• pharmaceutical intermediates
  
  

• agrochemical compounds
  
  

2. Flavor & Fragrance Chemistry

Thanks to its mild sweet notes, the compound can participate in the creation of:

• caramel-like aromas
  
  

• sweet or fruity flavor accents
  
  

• Maillard reaction analogs used in flavor development
  
  

Although not always used directly as a flavor additive, it frequently serves as a starting material for aroma compounds.

3. Pharmaceutical Research

The pyran framework is widespread in bioactive molecules. Tetrahydro-4H-pyran-4-one contributes to:

• synthesis of drug candidates
  
  

• heterocycle diversification
  
  

• formation of functional building blocks for medicinal chemistry
  
  

4. Material Science & Polymer Chemistry

Its structure allows integration into specialty polymers or advanced materials where oxygen-containing rings contribute to specific functional properties.

Why This Compound Is Important

Tetrahydro-4H-pyran-4-one stands out due to its balance of stability and reactivity. The ketone position enables versatile functional transformations, while the cyclic structure provides rigidity and defined stereochemistry—features valued in synthetic strategies.

Chemists appreciate it for:

• predictable reaction pathways
  
  

• usefulness in multi-step synthesis
  
  

• compatibility with diverse catalytic conditions
  
  

Whether used in academic research or industrial chemistry, it remains a valuable heterocyclic building block.

Safety & Handling Overview

As with many organic chemicals, standard laboratory safety procedures apply:

• Use in a well-ventilated area
  
  

• Wear appropriate protective equipment (gloves, goggles, lab coat)
  
  

• Store in tightly sealed containers away from strong oxidizing agents
  
  

Consult a material safety data sheet (MSDS) for full guidelines relevant to specific lab settings.

Conclusion

Tetrahydro-4H-pyran-4-one (CAS 29943-42-8) is a versatile and valuable compound in modern chemistry. Its structural simplicity paired with functional versatility makes it a go-to intermediate for researchers exploring heterocyclic chemistry, flavor science, pharmaceutical development, and related fields.

Its role as a building block continues to expand as new applications for oxygenated heterocycles emerge.