2-Di-tert-butylphosphino-2,4,6-triisopropylbiphenyl丨CAS 564483-19-8

Overview

2-Di-tert-butylphosphino-2,4,6-triisopropylbiphenyl丨CAS 564483-19-8 known as tBuBrettPhos, is a bulky, electron-rich monophosphine ligand derived from a biaryl backbone. It is engineered for palladium-catalyzed cross-coupling reactions, especially where steric hindrance, low catalyst loading, or difficult substrates are involved. The large tert-butyl and isopropyl groups provide both steric protection and electronic modulation, making it exceptionally efficient in challenging transformations.

Applications

1. Palladium-Catalyzed C–N Coupling

Key ligand in Buchwald–Hartwig amination, especially for coupling:

Aryl chlorides

Sterically hindered amines

Electron-deficient or deactivated aryl halides

2. C–O and C–F Bond Formation

Effective in C–O cross-coupling (e.g., aryl ethers) and other bond constructions where standard ligands often fail.

3. Cross-Coupling of Aryl Tosylates and Mesylates

Useful in activating phenol derivatives (like tosylates) that are otherwise reluctant coupling partners.

4. Low Catalyst Loading Conditions

Maintains high activity even with sub-mol% Pd loadings, making it suitable for scale-up and industrial applications.

5. Difficult Substrate Scope

Compatible with heteroaryl halides, secondary amines, and other traditionally challenging coupling partners.

Benefits

✅ High Reactivity with Aryl Chlorides

Aryl chlorides are abundant and inexpensive but less reactive; this ligand enables their efficient use.

✅ Broad Substrate Tolerance

Enables coupling of sterically hindered, electron-poor, and heterocyclic substrates.

✅ Low Catalyst Loading

Maintains performance with very low amounts of Pd, reducing costs and simplifying purification.

✅ Improved Selectivity and Yield

Designed to minimize side reactions, improving isolated yields and product purity.

✅ Versatility Across Reaction Types

Performs well in C–N, C–O, and C–C coupling, broadening its utility in synthetic chemistry.

Summary

2-Di-tert-butylphosphino-2,4,6-triisopropylbiphenyl丨CAS 564483-19-8, also known as tBuBrettPhos, is a high-performance, sterically demanding monodentate phosphine ligand tailored for modern Pd-catalyzed cross-coupling reactions. It offers exceptional reactivity with challenging substrates and excels under mild, scalable conditions-making it indispensable for both academic and industrial synthesis.