Title: Bis(pinacolato)diborane
CAS Registry Number: 73183-34-3
CAS Name: 4,4,4¢,4¢,5,5,5¢,5¢-Octamethyl-2,2¢-bi-1,3,2-dioxaborolane
Additional Names: Miyaura's reagent; pinacol diborane; 4,4,5,5-tetramethyl-1,3,2-dioxaborolan-1-yl-4¢,4¢,5¢,5¢-tetramethyl-1¢,3¢,2¢-dioxaborolan; B2pin2
Molecular Formula: C12H24B2O4
Molecular Weight: 253.94
Percent Composition: C 56.76%, H 9.53%, B 8.51%, O 25.20%
Literature References: Boron source for organic syntheses. Prepn and crystal structure: H. Nöth, Z. Naturforsch. 39b, 1463 (1984). Synthesis: T. Ishiyama et al., Org. Synth. 77, 176 (2000). NMR spectroscopic data: W. Biffar et al., Ber. 113, 333 (1980). First use as boron source in Pt-catalyzed diboration of alkynes: T. Ishiyama et al., J. Am. Chem. Soc. 115, 11018 (1993). Stereospecific synthesis via cross coupling with aromatic amine: C. Malan, C. Morin, J. Org. Chem. 63, 8019 (1998). Rh-catalyzed activation of the C-H bond: Y. Kondo et al., J. Am. Chem. Soc. 124, 1164 (2002). Brief review: X. Liu, Synlett 2003, 2442-2443.
Properties: Colorless plates, mp 138°. Crystalline form can be handled in air and stored in capped bottle.
Melting point: mp 138°
Use: As a boron source in Pt-mediated diborations, coupling reactions; in Rh-or Ir-mediated borylations of alkanes and arenes, and in carbenoid chemistry. |