Abbreviations B2pin2 | ||
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Bis(pinacolato)diboron is covalent compound containing two boron atoms and two pinacolato ligands. It has the formula [(CH3)4C2O2B]2; the pinacol groups are sometimes abbreviated as "pin", so the structure is sometimes represented as B2pin2. It is a colourless solid that is soluble in organic solvents. It is a commercially available reagent for making pinacol boronic esters for organic synthesis. Unlike some other diboron compounds, B2pin2 is not moisture-sensative and can be handled in air.
Contents
Preparation and structure
This compound may be prepared by reacting tetrakis(dimethylamino)diboron with pinacol in acidic conditions. The B-B bond distance is 1.711(6) Å.
Reactions
The B-B bond adds across alkenes and alkynes to give the 1,2-diborylated alkanes and alkenes. Using various organorhodium or organoiridium catalysts, it can also be installed onto saturated hydrocarbons:
CH3(CH2)6CH3 + [pinB]2 → pinBH + CH3(CH2)7BpinThese reactions proceed via boryl complexes.