CYCLOMANGANATED DERIVATIVES OF TRIPHENYLPHOSPHINE CHALCOGENIDES

Reaction of the triphenylphosphine chalcogenides Ph3P=E (E=O, S, Se) w ith PhCH2Mn(CO)(5) at 70-90 degrees C in hydrocarbon solvents gave the orthomanganated derivatives (OC)(4)MnC6H4P(E)Ph-2 in 41% (E = O), 90% (E = S) or 22% (E = Se) yields. The different yields are rationalised in terms of the preferred angles of coordination at the E atom and th e P=E bond stability. The new compounds were fully characterised inclu ding X-ray crystal structure determinations for the examples with E = S and Se. (OC)(4)MnC6H4P(S)Ph-2 reacted with P(OMe)(3) to replace two of the CO ligands without disrupting the Mn-S bond; an X-ray structure determination shows the two phosphite ligands are trans to each other , and have little effect on the geometry of the rest of the molecule.