Bispinacolatodiboron

Bispinacolatodiboron, more commonly known as bis(pinacolato)diboron or B2pin2, is an organoboron compound characterized by two boron centers connected by a B–B bond, each boron chelated by a pinacolato ligand. The molecule is symmetric and is widely described as two Bpin units linked together. It is a stable, often air-tolerant solid that serves as a versatile boron source in organic synthesis.

In chemical synthesis, B2pin2 is used to install boron groups into organic substrates through various borylation reactions. It is the standard boron donor in many transition-metal-catalyzed processes, including Suzuki–Miyaura cross-couplings, hydroborations, and radical borylations. These reactions enable the formation of alkyl-, alkenyl-, and aryl-boronates (RBpin) under relatively mild conditions and with broad tolerance for functional groups. B2pin2 is valued for its stability, easy handling, and compatibility with a wide range of catalysts and reaction conditions, contributing to its prominence in modern boron chemistry.

Availability and preparation are straightforward: B2pin2 is commercially available and is also prepared via established procedures from diboron sources and pinacol. Its robust nature and ease of use have made it a standard reagent in laboratories performing boron-based transformations.

Safety and handling follow general chemical precautions for boron reagents: use in a well-ventilated area, avoid inhalation, and store in a dry place. See also organoboron chemistry and pinacolboron reagents.