Di-tert-butylphenylphosphine
[CAS# 32673-25-9]

Identification

• Classification: Pharmaceutical intermediate >> OLED material intermediate
• Name: Di-tert-butylphenylphosphine
• Synonyms: NSC 244300; Phenyldi(tert-butyl)phosphine
• Molecular Formula: C₁₄H₂₃P
• Molecular Weight: 222.31
• CAS Registry Number: 32673-25-9
• EC Number: 625-553-0
• SMILES: CC(C)(C)P(C1=CC=CC=C1)C(C)(C)C

Properties

• Solubility: Insoluble (8.9E^-4 g/L) (25 °C), Calc.^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software V11.02 (©1994-2013 ACD/Labs)

Safety Data

• Hazard Symbols: GHS02;GHS07 Danger
• Risk Statements: H250-H315-H319-H335-H413
• Safety Statements: P210-P222-P231-P233-P261-P264-P264+P265-P271-P273-P280-P302+P335+P334-P302+P352-P304+P340-P305+P351+P338-P319-P321-P332+P317-P337+P317-P362+P364-P370+P378-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335
Pyrophoric liquids	Pyr. Liq.	1	H250
Chronic hazardous to the aquatic environment	Aquatic Chronic	4	H413

• Transport Information: UN 2845 4.2/PG 1

Discovery and Applications

Di-tert-butylphenylphosphine is an important organophosphorus compound known for its applications in catalysis and materials science. Di-tert-butylphenylphosphine was originally synthesized as part of a study of sterically hindered phosphines, which are known to affect reaction kinetics and selectivity. The compound is prepared by reacting phenylphosphine with tert-butyl halide under alkaline conditions. Typically, phenylphosphine is deprotonated to form a phosphide anion, which is then reacted with tert-butyl halide to introduce the tert-butyl group.

The resulting structure features a phosphorus atom bonded to a phenyl group and two tert-butyl groups, making it a phosphine ligand with significant steric bulk. This structure imparts unique electronic and steric properties that are essential for its use in catalysis.

Di-tert-butylphenylphosphine is a colorless liquid or solid, depending on its purity and storage conditions. Its chemical formula is C14H23P, and it exhibits significant steric hindrance due to the bulky tert-butyl group. This steric bulk affects its reactivity and interaction with metal centers in catalytic systems.

One of the main applications of di-tert-butylphenylphosphine is homogeneous catalysis. It is used as a ligand in transition metal complexes for a variety of catalytic processes, including hydrogenations, cross-couplings, and hydroformylation reactions. The steric bulk of the tert-butyl group provides a unique environment around the metal center, improving selectivity and efficiency in the catalytic cycle.

In cross-coupling reactions, such as the Suzuki-Miyaura and Heck reactions, the di-tert-butylphenylphosphine ligand helps stabilize the palladium complex, facilitating carbon-carbon bond formation. This stabilization is essential for the efficient synthesis of complex organic molecules, including pharmaceuticals and agrochemicals.

Di-tert-butylphenylphosphine has also been studied in asymmetric catalysis, where it helps create a chiral environment around the metal center. This is particularly important in the synthesis of enantiomerically pure compounds, which are essential in the pharmaceutical industry for the production of drugs with specific biological activities.

In materials science, di-tert-butylphenylphosphine is used in the synthesis of functional polymers. It can act as a ligand in polymerization catalysts, influencing the structure and properties of the polymer. Polymers synthesized using this phosphine often exhibit improved mechanical properties and thermal stability, making them suitable for high-performance applications.

The compound is also used to develop coordination polymers and metal-organic frameworks (MOFs). These materials, which consist of metal ions and organic ligands (such as di-tert-butylphenylphosphine), are used for gas storage, separation, and catalysis due to their porous structure and high surface area.

References

2019. The emergence of Pd-mediated reversible oxidative addition in cross coupling, carbohalogenation and carbonylation reactions. Nature Catalysis, 2(10).
DOI: 10.1038/s41929-019-0361-0

1997. Di- tert -butyl(N-pyrrolyl)phosphane,-sulfide, and-selenide, studied by multinuclear magnetic resonance. Fresenius' Journal of Analytical Chemistry, 357(3).
DOI: 10.1007/s002160050198

1976. Conformations of certain dialkylarylphosphines and their oxides. Bulletin of the Academy of Sciences of the USSR, Division of chemical science, 25(10).
DOI: 10.1007/bf02659523