Molybdenum and rhenium carbonyl complexes containing thiolato ligands

The reaction of fac-[M(OTf)(CO)3(N–N)](M = Mn, Re; N–N = 2,2′-bipyridine, 1,10-phenanthroline) complexes with in situ generated LiSEt afforded immediately, in THF at low temperature, the corresponding mononuclear terminal thiolato complexes fac-[M(SEt)(CO)3(N–N)](1-2a,b). Using an analogous synthetic strategy, tungsten and molybdenum (II) alkyl- and arylthiolatos of formula cis-[M(SR)(η3-allyl)(CO)2(N–N)] (3-6a,b) have been obtained. Preliminary reactions of the more reactive molybdenum thiolato complexes towards dimethylacetylenedicarboxylate led to Z-alkenyl products (7a,b), resulting from the insertion of the organic unsaturated electrophile into the Mo–S bond. For each new type of compound, one representative has been characterized in the solid state by X-ray diffraction.
Financial support from Ministerio de Economía y Competitividad/FEDER (grant CTQ2015-70231-P), Ministerio de Ciencia, Innovacion y Universidades (grant PGC2018-097366-B-100), and Principado de Asturias (grant GRUPIN14-103, and Severo Ochoa predoctoral fellowship to S. F.) is gratefully acknowledged. S. Z. participated in this work during her stay at Universidad de Oviedo as an Erasmus exchange student from University of Heidelberg.