Synthesis of monomercurated N-protected pyrroles and the use of these compounds as pyrrolyl group transfer reagents to ruthenium and osmium. Crystal structures of (2-C4H3NCCH3)HgCl, (2-C4H3NCCH3)2Hg and

Article abstract of DOI:10.1016/0022-328X(94)05213-U

N-Acetylpyrrole and N-phenylsulfonylpyrrole are each selectively mercurated in the 2-position on treatment with mercuric chloride.The resulting organomercuric chlorides are symmetrized to the corresponding diorganomercury derivatives (2-C4H3NCCH3)2Hg (2) and (2-C4H3NSOPh)2Hg (4) by the action of sodium iodide.The crystal structures of (2-C4H3NCCH3)HgCl (1) and (2-C4H3NCCH3)2Hg (2) have been determined.The acetyl oxygen atom interacts weakly with the mercury centre in both cases, but more strongly in 1 than 2.Treatment of the hydrido complexes MHCl(CO)(PPh3)3 (M = Ru, Os) with the diorganomercurial 2 or 4 affords in good yield the 2-pyrrolyl complexes M(2-C4H3NCCH3)Cl(CO)(PPh3)2 or , respectively.In each case the pyrrolyl group is coordinated in a bidentate fashion through C-2 and an oxygen atom of the N-substituent.The chloride ion in (7) is labile, and upon treatment with AgSbF6 and CO, the cationic complex is formed.Treatment of 7 with AgSbF6 and sodium dimethyldithiocarbamate gives the neutral monophosphine complex (10), the crystal structure of which has been determined.Keywords: Mercury; Ruthenium; Osmium; Pyrrole; Crystal structure