Bis(pinacolato)diboron
[CAS# 73183-34-3]

Identification

• Classification: Chemical reagent >> Organic reagent >> Boric acid
• Name: Bis(pinacolato)diboron
• Synonyms: 4,4,4',4',5,5,5',5'-Octamethyl-2,2'-bi-1,3,2-dioxaborolane
• Molecular Formula: C₁₂H₂₄B₂O₄
• Molecular Weight: 253.94
• CAS Registry Number: 73183-34-3
• EC Number: 615-925-0
• SMILES: B1(OC(C(O1)(C)C)(C)C)B2OC(C(O2)(C)C)(C)C

Properties

• Melting point: 135-140 °C

Safety Data

• Hazard Symbols: GHS05;GHS07;GHS08 Danger
• Risk Statements: H302-H314-H315-H317-H319-H332-H335-H341
• Safety Statements: P203-P260-P261-P264-P264+P265-P270-P271-P272-P280-P301+P317-P301+P330+P331-P302+P352-P302+P361+P354-P304+P340-P305+P351+P338-P305+P354+P338-P316-P317-P318-P319-P321-P330-P332+P317-P333+P317-P337+P317-P362+P364-P363-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute toxicity	Acute Tox.	4	H302
Acute toxicity	Acute Tox.	4	H332
Skin sensitization	Skin Sens.	1	H317
Skin corrosion	Skin Corr.	1C	H314
Skin irritation	Skin Irrit.	2	H315
Germ cell mutagenicity	Muta.	2	H341
Eye irritation	Eye Irrit.	2A	H319
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Acute toxicity	Acute Tox.	4	H312
Skin corrosion	Skin Corr.	1	H314

Discovery and Applications

Bis(pinacolato)diboron is a widely studied chemical compound notable for its significance in organic synthesis and materials science. This compound, often abbreviated as BPin2, consists of two pinacolato ligands coordinated to a central boron atom. The development and application of Bis(pinacolato)diboron have contributed significantly to advances in boron chemistry and its use in various scientific fields.

The discovery of Bis(pinacolato)diboron can be traced back to the early 1970s when researchers were exploring the chemistry of boron compounds and their potential applications. The synthesis of Bis(pinacolato)diboron involves the reaction of boron trichloride with pinacol, resulting in the formation of this boron-containing molecule. The unique structure of Bis(pinacolato)diboron, with its two pinacolato groups attached to a central boron atom, gives it distinctive chemical properties that have made it valuable in multiple areas of research.

In organic synthesis, Bis(pinacolato)diboron is primarily used as a reagent in cross-coupling reactions, such as the Suzuki-Miyaura reaction. This reaction involves the coupling of an aryl or vinyl boronic acid with an aryl or vinyl halide in the presence of a palladium catalyst. The use of Bis(pinacolato)diboron in these reactions has proven advantageous due to its stability and ease of handling compared to other boron reagents. The compound facilitates the formation of carbon-carbon bonds, which is crucial in the synthesis of complex organic molecules, including pharmaceuticals, agrochemicals, and functional materials.

Bis(pinacolato)diboron also finds applications in materials science. The compound can be used to create boron-containing polymers and materials with specific electronic or optical properties. For example, the incorporation of Bis(pinacolato)diboron into polymer matrices can enhance the material's performance in electronic devices or sensors. The compound's ability to form stable boron-containing linkages makes it an important building block for designing advanced materials with tailored properties.

In medicinal chemistry, Bis(pinacolato)diboron has been utilized to develop new drugs and therapeutic agents. The compound's role in facilitating the synthesis of complex organic molecules has enabled researchers to create novel pharmaceuticals with potential therapeutic applications. Its use in drug discovery and development underscores its importance in advancing medical research and improving healthcare outcomes.

Overall, Bis(pinacolato)diboron is a versatile and valuable chemical compound with significant applications in organic synthesis, materials science, and medicinal chemistry. Its discovery and development have greatly contributed to the field of boron chemistry, enabling the creation of complex molecules and advanced materials with a wide range of applications.

References

2024. Photoelectrochemically driven iron-catalysed C(sp3)-H borylation of alkanes. Nature Synthesis, 3(3).
DOI: 10.1038/s44160-023-00480-7

2002. Palladium-Catalyzed Cross-Coupling Reaction of Bis(pinacolato)diboron with 1-Alkenyl Halides or Triflates: Convenient Synthesis of Unsymmetrical 1,3-Dienes via the Borylation-Coupling Sequence. Journal of the American Chemical Society, 124(25).
DOI: 10.1021/ja0202255

2002. Organoboron Compounds. Topics in Current Chemistry.
DOI: 10.1007/3-540-45313-x_2