4-tert-Butylthiophenol: A Valuable Aromatic Thiol for Organic and Material Chemistry

Introduction

4-tert-Butylthiophenol is a specialized aromatic thiol widely used in organic synthesis, materials science, and surface modification. This compound is known for its unique sulfur functionality combined with a sterically hindered tert-butyl group, making it a versatile reagent and intermediate in chemical industries.

Chemical Identity

• Chemical Name: 4-tert-Butylbenzenethiol

• Synonyms: p-tert-Butylthiophenol, 4-(tert-Butyl)thiophenol

• Molecular Formula: C10H14S

• Molecular Weight: 166.28 g/mol

• CAS Number: 98-29-3

• Appearance: Colorless to pale yellow liquid with a distinct thiol odor

• Solubility: Insoluble in water; soluble in organic solvents like ethanol, diethyl ether, and benzene

Structure and Reactivity

The compound contains:

• A thiol (-SH) group at the para-position of a benzene ring

• A tert-butyl group (-C(CH₃)₃) that provides steric bulk and hydrophobicity

This structure makes 4-tert-butylthiophenol an excellent nucleophile, especially in reactions where selective functionalization of surfaces or molecules is desired.

Applications of 4-tert-Butylthiophenol

1. Ligand in Metal Coordination Chemistry

The thiol group readily binds to transition metals such as gold, silver, and copper, making it a key component in:

• Self-Assembled Monolayers (SAMs) on gold surfaces

• Design of metal-organic frameworks (MOFs)

• Catalytic systems where sulfur-metal interactions are crucial

2. Surface Functionalization and Nanotechnology

4-tert-Butylthiophenol is commonly used to modify the surface properties of metals, especially:

• Gold nanoparticles and electrodes for sensor applications

• Corrosion-resistant coatings

• Functional thin films for electronic and biomedical devices

The tert-butyl group provides hydrophobicity and steric control, making it suitable for engineering surface wettability and reactivity.

3. Organic Synthesis Intermediate

It serves as a valuable intermediate in the synthesis of:

• Pharmaceutical compounds

• Polymers

• Agrochemicals

• Functional aromatic sulfides and sulfoxides

Its reactivity enables formation of C–S bonds via substitution and oxidation reactions, useful for tailoring molecular frameworks.

4. Precursor for Disulfide and Thioether Synthesis

Through controlled oxidation or alkylation, 4-tert-butylthiophenol can be converted into:

• Disulfides (R–S–S–R)

• Thioethers (R–S–R’)

• Sulfonic acids or sulfoxides for medicinal and polymer chemistry

Handling and Safety

• Toxicity: Harmful if inhaled or ingested; can cause irritation to skin and eyes

• Odor: Strong thiol odor; use in well-ventilated area or fume hood

• Storage: Keep in a cool, dry, and tightly closed container away from oxidizers

• Protective Equipment: Gloves, lab coat, safety goggles, and appropriate respiratory protection

Refer to the Material Safety Data Sheet (MSDS) for detailed handling instructions.

Packaging and Availability

4-tert-Butylthiophenol is available in:

• Analytical & research grades (1g, 5g, 25g)

• Industrial-scale quantities (100g, 1kg, 5kg)

• Custom purity specifications upon request

Supplied with COA, MSDS, and TDS. Custom packaging for moisture-sensitive or air-sensitive use available.

Conclusion

4-tert-Butylthiophenol is a high-value aromatic thiol with applications ranging from nanotechnology and catalysis to drug synthesis and surface chemistry. Its reactivity, stability, and tunable properties make it a preferred choice for chemists and material scientists.

✅ Summary:

• Strong metal-binding thiol group

• Excellent for gold surface modification

• Precursor to disulfides, thioethers, and sulfonic acids

• Widely used in materials science and organic synthesis

• Available in both research and industrial grades

Chemical Properties & Reactivity

4-tert-Butylthiophenol is a substituted benzenethiol, combining a strongly nucleophilic thiol group (-SH) with a bulky tert-butyl group at the para position. The presence of the bulky tert-butyl moiety adds:

• Steric hindrance, reducing over-oxidation of the thiol

• Enhanced lipophilicity (fat solubility)

• Improved thermal and oxidative stability

Key Functional Groups:

• Thiol (-SH): Highly reactive, forms strong covalent bonds with soft metals (Au, Ag, Cu)

• tert-Butyl (-C(CH₃)₃): Inert bulky group that modifies reactivity and solubility

🧪 Synthetic Pathways

4-tert-Butylthiophenol can be synthesized via several methods:

1. Thiolation of 4-tert-butylphenol

A nucleophilic substitution where thiol reagents replace hydroxyl or halogen groups in para-substituted aromatic rings.

2. Reduction of 4-tert-Butylbenzenesulfonyl Chloride

• Reagents like LiAlH₄, NaBH₄, or hydrogenation catalysts are used

• Provides high-purity thiophenol derivatives

3. Grignard Method

Reaction of 4-tert-butylphenylmagnesium bromide with sulfur, followed by acid work-up to introduce the thiol.

These processes are scalable and suitable for industrial-scale production, especially for materials and fine chemicals manufacturing.

🧬 Advanced Applications

1. SAMs on Gold Surfaces

4-tert-Butylthiophenol is often used in forming Self-Assembled Monolayers (SAMs), which are:

• Monolayers formed via thiol-metal chemisorption

• Used in biosensors, nanoelectronics, and microfluidic devices

• Help in tuning surface energy, biocompatibility, or hydrophobicity

2. Corrosion Resistance & Surface Coatings

Its use in anti-corrosion coatings improves:

• Adhesion of organic coatings on metal substrates

• Hydrophobic surface protection

• Enhanced performance of electrochemical devices

3. Ligand in Catalysis

As a soft ligand, 4-tert-butylthiophenol forms stable complexes with Pd, Pt, Au, and Ru, used in:

• Cross-coupling reactions (Suzuki, Heck, etc.)

• Olefin metathesis and polymerization catalysts

• Nanocatalysts for green chemistry

4. Optical & Electronic Applications

Its derivatives are explored in:

• OLED materials and photoresists

• Conductive self-assembled layers for nano-fabrication

🌍 Market Demand & Industrial Relevance

Industries Using 4-tert-Butylthiophenol:

Due to its versatile functional group chemistry, demand is growing across:

• Specialty chemical manufacturers

• Contract Research Organizations (CROs)

• Materials and polymer labs

🧯 Toxicity, Storage, and Handling

Refer to MSDS for specific thresholds and personal protective equipment (PPE) requirements.

🧾 Product Forms and Packaging Options

Available in:

• Lab-scale quantities: 1g, 5g, 25g vials

• Bulk industrial: 100g, 500g, 1kg, 5kg drums

• Custom concentrations for formulation and process chemistry

Supplied with:

• Certificate of Analysis (COA)

• Material Safety Data Sheet (MSDS)

• TDS (Technical Data Sheet)

• Purity: typically ≥98%, available in ≥99.5% on request