107939-79-7Relevant academic research and scientific papers
Cycloaddition of alkynes to CpFe(CX)(CY)SR (CX, CY = CO, CS, CNCH3) to give RSFeC(=Y)C=C heterometallacycles
Ashby, Michael T.,Enemark, John H.
, p. 1318 - 1323 (2008/10/08)
CpFe(CO)2SC6H5 undergoes a cycloaddition reaction with dimethyl acetylenedicarboxylate (DMAD) to give the five-member heterometallacycle Cp(CO)FeS(C6H5)C(CO2CH3)=C(CO 2CH3)C=O that crystallizes in the monoclinic space group P21/n with a = 5.941 (1) ?, b = 18.246 (5) ?, c = 17.311 (5) ?, β = 96.50 (2)°, V = 1864.4 (9) ?3, and Z = 4. The structure was solved by direct methods followed by least-squares refinement using 2403 independent reflections to a final R value of 0.054 (Rw = 0.065). Compounds of the type CpFe(CX)(CY)SC6H5 have been prepared where CX and CY are pairwise combinations of carbonyl, thiocarbonyl, and methyl isocyanide ligands. These compounds also react with DMAD to yield five-member heterometallacycles. Competition between a carbonyl or a thiocarbonyl ligand with a methyl isocyanide ligand results in preferential incorporation of the isocyanide into the heterometallic ring. Competition between a carbonyl and a thiocarbonyl ligand results in an unprecedented attack on the carbonyl rather than the thiocarbonyl ligand. The regiochemistry of the cycloaddition products favors a concerted mechanism with a highly ordered transition state.
