mu-1,5-Pentanediyldilithium

UsesUsed as constructing block agent: transformations of carboxyl groups and metal halides into cyclohexane and metallacyclohexane synthetic intermediates, and α,ο-bifunctional compounds; in presence of CuI ion, the reagent is transformed into an organobiscuprate.

Preparation1,5-Dilithiopentane was first prepared by direct reaction of 1,5-dibromopentane with Lithium metal at 0 °C in anhydrous ether. This method was later improved by using lithium metal (4 equiv) containing 1% Na with 1,5-dichloropentane (1 equiv). The optimum procedure uses a 12.5% excess of lithium and maintains the temperature at 0 °C (eq 1). Yields up to 90% can be obtained by this method, which may also serve to prepare lower analogs.