Tetrahydrofuran complexes with organolithium

This complex should be used when the organolithium is in solution in a hydrocarbon solvent. For organolithium reagents prepared in ether (see Note 4), the same complex may be used or, more conveniently, copper iodide (Cull can be used. The Cul purchased from Prolabo or Merck 4 Company, Inc. may be used directly. Other commercial sources of Cul (Fluka, Aldrich Chemical Company, Inc., Alfa Products, Morton/Thiokol, Inc.) furnish a salt which affords better results when purified. 1 mol of Cul is stirred for 12 hr with 500 ml of anhydrous tetrahydrofuran, then filtered on a sintered glass funnel ( 3), washed twice with 50 ml of anhydrous tetrahydrofuran, once with 50 ml of anhydrous ether and finally dried under reduced pressure (0.1 imO for 4 hr. 

White phosphorus also reacts with carbon nucleophiles in ether or tetrahydrofuran to give dark red solutions believed to be complex organophosphides (Rauhut and Semsel). Hydrolysis of a mixture obtained from reactions of white phosphorus with organolithium and organomagnesium compounds gives the primary phosphine as the major product, with small amounts of secondary and tertiary phosphines being formed under some conditions. 

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