Synthesis of transition metal carbonyl complexes of heterocyclic ligands

Abstract

The complex [Mn2(PySMCO)6J 1 was prepared from reaction between [Mn2(CO)lOJ and pyridine-2-thiol (pySH) by refluxing in cyclohexane. The same complex was also prepared at room temperature in dichloromethane in presence of trimethylamino oxide. The crystal structure of the complex was determined by X-ray Crystallography. The reactions of 1 with a variety of phosphine ligands were carried out and the product complexes were characterized by elemental analysis (C, H,.N), IR, lH, 13CCH} and 31pCH} NMR and mass spectroscopy. The monomeric complexes jac-[Mn(pyS)(PHPh2)(CO)3J 2 , jac-[Mn(pyS)(PPh3)(CO)3J 3 and [Mn(pyS)(rrdppmMCO)2J 4 were prepared from the reactions of 1 with PHPh2, PPh3 and dppm (Ph2PCH2PPh2)respectively. H2y..,A'Ph, o PPh, o~oI/Il':\"~ iPh,S Ph,~H, (4) I ,2-bis-( diphenylphosphino )ethane, Ph2PCH2CH2PPh2 (dppe), gave the dimeric complex [MnzepySMT]I-dppe)(CO)sJ 5 in addition to the expected monomeric complex [Mn(pyS)- (T]2-dppe)(CO)2J6, but 1,3-bis(diphenylphosphino)propane, Ph2PCH2CH2CH2PPh2 (dppp) gave only the monomeric complex [Mn(pyS)(T]2-dppp)(CO)2J 7. (5) (6) (7) " In contrast to the reactions of these phosphine ligands with 1, the long chain phosphine ligand I,5-bis( diphenylphosphino )pentane, Ph2PCH2CH2CH2CH2CH2PPh2 (dpppe), reacted with 1 to give a highly insoluble polymer complex [Mn(pyS)(COMdpppe)]n 8. Ph2P - (CH2h - rhz rh2 - (CH2h---- t'HC~) >>t) ~J'~) > (8) The crystal structures of 4 and 7 were determined by X-ray crystallography. The complex 4 reacted with the labile complex [Os3(CO)11(MeCN)] to give the known complex [OS3(CO)1O(1l2-dppm)]9 which was characterized by infrared, IH and 31p{'H} NMR and mass spectroscopic methods. But a similar reaction of 4 with the labile complex [Re2(COMMeCN)] gave the Mn-Re cluster [Mn(pyS)(1l2-dppmMCOHRe2(CO~h] 10 which was characterized by infrared and 31peH}NMR spectroscopy. (9) In contrast to the reaction of pySH with [Mn2(CO)1O],pySH reacted with [C02(CO)s], both thermally and at room temperature, to give the monomeric complex mer-[Co(pyS)3] 11. The X-ray crystal structure of this complex was also determined.