DIRECT TRANSFORMATION OF DIALKYL SULFATES INTO ALKYLLITHIUM REAGENTS BY A NAPHTHALENE-CATALYZED LITHIATION

The lithiation of primary and secondary dialkyl sulfates with an excess of lithium powder in the presence of a catalytic amount of naphthalene (4 mol %) in THF at -78 degrees C leads to the corresponding alkyllithium reagents (1:2 molar ratio) which react with different electrophiles, mainly carbonyl compounds, to yield after hydrolysis, the expected coupling products. This methodology represents an indirect way to transform alcohols into organolithium compounds through the corresponding dialkyl sulfates. When the same procedure is applied to five or six member cyclic sulfates (derived from 1,2- or 1,3-diols) only products arising from a beta- or gamma-elimination process (giving olefins or cyclopropanes), respectively, are obtained.