Preparation and protonation reactions of aryl complexes of manganese and rhenium

Aryl M(κ1-Ar)(CO)nP5−n [M = Mn, Re; Ar = C6H5, 4-CH3C6H4; n = 2, 3; P = P(OEt)3, PPh(OEt)2, PPh2OEt] and Re(κ1-C6H5)(CO)3[Ph2PO(CH2)3OPPh2] complexes were prepared by allowing hydrides MH(CO)nP5−n to react first with triflic acid and then with the appropriate aryl lithium (LiAr) compounds. The complexes were characterized spectroscopically (IR and 1H, 31P, 13C NMR) and by the X-ray crystal structure determination of Re(κ1-C6H5)(CO)3[Ph2PO(CH2)3OPPh2] derivative. Protonation reaction of the aryl complexes with HBF4 · Et2O lead to free hydrocarbons Ar–H and the unsaturated [M(CO)nP5−n]+ cations, separated as solids in the case of [Re(CO)3P2]BF4 derivatives.

Graphical abstractThe preparation of aryl complexes M(η1-Ar)(CO)nP5−n of manganese and rhenium is presented. The structural parameters of the Re(η1-C6H5)(CO)3[Ph2PO(CH2)2OPPh2] derivative was also determined. The protonation of the aryl complexes with Brønsted acid was studied and led to free hydrocarbons and the unsaturated [M(CO)nP5−n]+ cations.Figure optionsDownload full-size imageDownload as PowerPoint slide