The Ammonium Salt Route to Oligomeric Lanthanum Salt Complexes: Synthesis and X‐Ray Crystal Structure of La(NCS)₃· 4 HMPA

Lanthanoid and transition metal complexes can be prepared under extremely mild conditions and water‐free by the so‐called ammonium salt route. A mixture of metal powder and ammonium salt in toluene/hexamethyl‐phosphoric triamide (HMPA) was first treated ultrasonically and then heated to 90 °C. The resulting complexes, e.g., the title compound 1, are present as monomers in the crystal. The anhydrous complex salts should be suitable as precursors for the vapor phase deposition of metal oxide films. (Figure Presented.)