Date of this Version
Patent Number: 5,211,889
A soluble highly reactive form of calcium, prepared from Ca(II) salts and a reducing agent in ethereal, polyethereal, or hydrocarbon solvents, is presented. This form of calcium can be used in the preparation of organocalcium reagents. The organocalcium reagents resulting from the reaction of the soluble highly reactive calcium with organic compounds containing either halide, cyanide, a 1,3-diene, or a polyunsaturated functionality, are stable, useful reagents for organic synthesis. The organocalcium halide reagents undergo Grignard-type reactions. They also undergo reactions with Cu(I) salts to form organocalcium cuprate reagents. The organocalcium cuprate reagents undergo a variety of cross-coupling reactions. The soluble highly reactive calcium reacts with 1,3-dienes to yield the corresponding 2-butene-1,4-diylcalcium complexes. These bis organocalcium reagents can undergo dialkylation reactions with a,c)-alkylene dihalides and dichlorosilanes to form the corresponding 3-, 5-, and 6-membered ring derivatives. The soluble highly reactive calcium also reacts with organic dihalides to form mono- or dior-ganocalcium compounds which can be converted into a wide variety of polymers.