Method C: In an N2 filled glovebox, 31.5 mg Ph2PH (29.5 μl, 0.170 mmol) was added dropwise at -30 °C to a scintillation vial containing a toluene solution of 15 mg (0.057 mmol) Cu(acac)2 and 11.5 mg (0.057 mmol) of P( t Bu)3. The solution allowed to warm to ambient temperature and stirred for 24 h. Then the solvent was removed under reduced pressure, the residue was taken up in pentane, filtered through a bed of Celite, and placed in a freezer at -30 °C. The resultant precipitate was dissolved in a minimum amount of THF ~ 1 mL and layered with three mL of pentane and placed in the freezer again. The 10.6 mg (53% yield) of solid was isolated by decanting the mother liquor, washing with cold pentane, and drying. The 1 H and 31 P NMR spectra of the compound obtained by this method matched methods A and B.