Microwave Assisted Synthesis of Molybdenum and Tungsten Tetracarbonyl Complexes with a Pyrazolylpyridine Ligand. Crystal structure of cis-[Mo(CO)4{ethyl[3-(2-pyridyl)-1-pyrazolyl]acetate}]

Abstract

We report the one-step syntheses in good yields of the complexes cis-[M(CO)4(pzpy)] {M = Mo, W; pzpy = ethyl[3-(2-pyridyl)-1-pyrazolyl]acetate} directlyfrom the corresponding M(CO)6 starting materials by using microwave-assisted heatingand reaction times of either 30 s (M = Mo) or 15 min (M = W). The structure of themolybdenum tetracarbonyl complex was determined by single crystal X-ray diffraction.The compound is monomeric and the molybdenum atom has a highly distorted octahedralgeometry. The close packing of the individual cis-[Mo(CO)4(pzpy)] species is essentiallydriven by the need to fill the space effectively, closely mediated by weak C–H···O andπ···π interactions.