The NiCl2•2H2O-Li-arene (cat.) combination as reducing system part 5 -: Reduction of sulfonates and aromatic compounds with the NiCl2•2H2O-Li-arene (cat.) combination

A series of alkyl mesylates, dimesylates and alkyl or aryl triflates have been reduced to the corresponding hydrocarbons with nickel(II) chloride dihydrate, an excess of lithium powder and a catalytic amount of DTBB (10 mol%) in THF at room temperature. This methodology applied to enol triflates allowed the preparation of olefins or alkanes depending on the amount of the Ni(II) salt used. The reduction of different aromatic or heteroaromatic compounds under the above mentioned conditions leads to the partial or total reduction of the starting materials, the process being a reasonable alternative to the well-known Birch reaction. The use of the deuterium oxide-containing nickel(II) salt allows the simple preparation of deuterated products. (C) 1999 Elsevier Science Ltd. All rights reserved.