Subido por Aaron Lemoine

Synthesis of (C6H5)PCH2CH2P(C6H5)2 in Liquid Ammonia

Supporting Information
Synthesis of (C6H5)PCH2CH2P(C6H5)2 in Liquid Ammonia
Aaron Lemoine
I. General Information/Materials and Methods
II. Synthesis of 1,2-bis(diphenylphosphino)ethane [DPPE]
III. 1,2-Bis(diphenylphosphino)ethane nickel(II) chloride [NiCl2(DPPE)]
General Information: Both 1H and 31P NMR spectra were recorded using a 400 MHz Varian
Unity. Chemical shifts for the 1H NMR spectra were reported relative to the deuterated
chloroform (CDCl3), which was determined to have a chemical shift of 7.24. Chemical shifts for
the 31P spectra were reported relative to H3PO4 with a chemical shift of 0.
Method and Materials: The DPPE utilized in the second half of the experiment was synthesized
using the previous period. For the DPPE synthesis all reagents were obtained from Sigma
Aldrich and solvents were obtained from Fisher Science. For the synthesis of Ni(DPPE)Cl2 the
NiCl2 was obtained from Sigma Aldrich and the diethyl ether from Fisher Scientific. NMR
spectra were recorded using a 400 MHz Varian Unity at the NMR laboratory at Roger Adam’s
Laboratory, Champaign IL.
Synthesis of 1,2-bis(diphenylphosphino)ethane[DPPE]: To a 500 mL three neck round bottom
flask a dry ice condenser is attached, followed by addition of a glass stir bar, after which the
flask was filled with 200 mL of liquid ammonia. After filling the condenser one quarter full with
ethanol and dry ice .11g of sodium was added to the reaction flask. To this deep blue colored
solution 13.14 g of triphenylphosphine were added over the course of five portions resulting in
the conversion from blue to orange color. The flask was then gently stirred and 4.92 g of NH4Br
was added to the reaction mixture along with a solution consisting of 2.48g of 1,2-dichloroethane
in 20 mL of ether. After letting the flask sit for one week, 100 mL of water and75 mL of
dichloromethane were added to the reaction flask. The contents of the flask were then transferred
to a separator funnel, where the organic phase was allowed to drain into a 250 mL round bottom
flask containing 100 mL of ethanol. The resulting solution was then placed in the rotary
evaporator for approximately 30 minutes. After filtering off the excess solvent 7.934 grams of
white crystalline solid were recovered. 1H NMR (400 MHz, CDCl3, δ): 7.31(d, 20H, CH),
3.72(q, N.A), 2.1(s, 4H, CH2), 1.59(s, H2O) 1.25(t, CH3). 31P NMR (400 MHz, CDCl3, δ): 11.59(s, R3P). Despite the large amount of solvent peaks present in the sample, the remaining
peaks are in good accordance with the literature data for DPPE.1
Synthesis of 1,2-Bis(diphenylphosphino)ethane nickel(II) chloride [NiCl2(DPPE)]
To a 200 mL beaker a .323g of NiCl2 in 50 mL of ethanol solution was added along with .527g
of the previously synthesized DPPE. The mixture was then stirred for a brief period until it
became dark orange. Vacuum filtration was then used to isolate the product, leaving behind .45g
of dark orange powder. 1H NMR (400 MHz, CDCl3, δ): 7.99(s, 4.42H), 7.33(t, 20.42H), 2.13(s,
4H, CH2), 1.63(s, CH2). 31P NMR (400 MHz, CDCl3, δ): 58.30(s,Ni(dppe)Cl2) -1.66(s,
Me3PBH3), -11.64(s, DPPE). The spectra data overall fit reasonably well with the literature data2,
but some problems were noted during the 31P analysis. The spectra appeared to show large
amounts of noise and peaks corresponding to leftover DPPE, indicating an incomplete reaction,
possibly due to time constraints.
Whiteker, G. T. Encyclopedia of Reagents for Organic Synthesis 2001.
Oberhauser, W.; Bachmann, C.; Stampfl, T.; Haid, R.; Brüggeller, P. Polyhedron 2827.