Kalipada Kundu

Some pyridine-2-thiolato and 6-methylpyridine-2-thiolato complexes of manganese: crystal structure of [Mn2(μ-pyS)2(CO)6] (pyS = pyridine-2-thiolato ligand)

Abstract The complexes [Mn 2 (μ-pyS) 2 (CO) 6 ] ( 1 ) and [Mn 2 (μ-MepyS) 2 (CO) 6 ] ( 2 ), where pySH = pyridine-2-thiol and MepySH = 6-methylpyridine-2-thiol, have been made by reaction of Mn 2 (CO) 10 with the appropriate pyridinethiol in refluxing hexane. In these complexes pyS and MepyS act as both six electron donor chelating and bridging groups which form four-membered N,S chelate rings at one metal centre and bridge to the other metal atom through sulphur. Complex 2 reacts with PPh 3 and Ph 2 PCH 2 PPh 2 (dppm) in refluxing cyclohexane to give [Mn(MepyS)(PPh 3 (CO) 3 ] ( 3 ) and [Mn(MepyS)( η 1 -dppm) 2 (CO) 2 ] ( 4 ) respectively. The crystal structure of 1 was determined.

Reactions of [Mn2(μ-pyS)2(CO)6] (pySH=pyridine-2-thiol) with triphenylphosphine (PPh3), diphenylphosphine (PHPh2) and bis(diphenylphosphino)methane (dppm): X-ray crystal structure of [Mn(pyS)(η1-dppm)2(CO)2]

The dimeric complex [Mn2(μ-pyS)2(CO)6] (1) reacted with 2 M equivalents of both PPh3 and PHPh2 to give the respective monomeric phosphine complexes [Mn(pyS)(L)(CO)3][L = PPh3 (2) and PHPh2 (3)]; with 4 M equivalents of dppm, it yielded the complex [Mn(pyS)(η1-dppm)2(CO)2](4). An X-ray structure determination of 4 shows that it crystallizes in the monoclinic space group P21/n with a = 11.027(3), b = 24.984(7), c = 18.379(5) Å, β = 99.870(8)°, V = 4988(2) Å3, and Z = 4. The complex has an octahedral geometry with the chelating pyS ligand and two CO groups occupying the equatorial sites and the two monodentate dppm ligands lying in the trans positions.

Reaction between [Ru3(CO)10(μ-dppm)] (dppm = Ph2PCH2PPh2) and Te2(C6H4OEt-4)2: X-ray crystal structure of [Ru2(CO)6{μ-C6H4PPh(CH2)PPh}]

Treatment of [Ru3(CO)10(μ-dppm)] (1) with the ditelluride Te2(C6H4OEt-4)2 in refluxing toluene afforded the new aryltellurol bridged complex [Ru2(CO)4(μ-TeC6H4OEt-4)2 (μ-dppm)] (2) together with three known complexes [Ru4(CO)8(μ-CO)(μ4-Te)2(μ-dppm)] (3), [Ru2(CO)6{μ-CH2PPh(C6H4)PPh}] (4), and [Ru2(CO)6{μ-C6H4PPh(CH2)PPh}] (5). All the four complexes were characterized by spectroscopic methods, including an X-ray structure determination for 5. Complex 5 crystallizes in the monoclinic space group P21/c with a = 13.650(2), b = 9.995(2), c = 18.929(3) Å, β = 97.49(2)°, V = 2560.4(8) Å3, and Z = 4. In this complex the two ruthenium atoms are bridged by the phosphino-phosphide ligand C6H4PPh(CH2)PPh which is attached to one Ru by the C6H4 group and a P atom while to the other Ru by both the two P atoms. Both the ruthenium atoms show distorted octahedral geometry. The Ru—Ru bond length is 2.8719(7) Å.

Reactions of [Mn2(μ-pyS)2(CO)6] with bidentate N-donor ligands: Crystal structure of [Mn(η1-pyS)(bipy)(CO)3] (bipy = 2,2′-bipyridyl, pySH = pyridine-2-thiol)

The dimeric complex [Mn2(μ-pyS)2(CO)6] (1) reacted with 2 equivalents of 2,2′-bipyridyl (bipy), 1,10-phenanthroline (phen), and ethylenediamine (en) to give the corresponding monomeric complexes [Mn(η1-pyS)(bipy)(CO)3] (2), [Mn(η1-pyS)(phen)(CO)3] (3), and [Mn(η 1-pyS)(en)(CO)3] (4). The pyS ligand in these complexes acts as a monodentate, two-electron donor ligand, which coordinates to manganese through the sulfur atom. This is confirmed by an X-ray structure determination of 2, which contains two structural isomers in the asymmetric unit. Crystals of this compound are the monoclinic, space group P21/c, a = 21.593(4), b = 10.463(2), c = 16.385(3) Å, β = 102.468(13)°, V = 3614.5(12) Å3, and Z = 8. The three CO groups are facially distributed in both isomers, but the relative positions of the pyS and bipy ligands are different.

Reactions of [Mn2(μ-pyS)2(CO)6] with bidentate phosphines: X-ray structure of [Mn(η2-pyS) (η2-dppp)(CO)2] [dppp = Ph2P(CH2)3PPh2, pySH = pyridine-2-thiol]

The dimeric complex [Mn2(μ-pyS)2(CO)6] (1) reacted with 2 molar equivalents of Ph2P(CH2)3PPh2 (dppp) and Ph2P(CH2)2PPh2 (dppe) to give the respective monomeric chelate complexes [Mn(η2-pyS)(η2-dppp)(CO)2] (2) and [Mn(η2-pyS)(η2-dppe)(CO)2] (3). In contrast, with 2 molar equivalents of Ph2P(CH2)5PPh2 (dpppe), 1 gave the highly insoluble polymeric complex [Mn(η2-pyS)(μ-dpppe)(CO)2]n (4). An X-ray structure determination shows that 2 crystallizes in the monoclinic space group P21/n with a = 10.721(2) Å, b = 19.712(5) Å, c = 14.846(4) Å, β = 109.06(2)°, V = 2965.5(14) Å3, and Z = 4. The complex has a distorted octahedral geometry with the dppp ligand, one CO group and the N atom of the chelating pyS ligand occupying equatorial sites, and one CO group and the S atom of the pyS ligand lying in the axial positions.