Reactions of Manganese and Rhenium Vinylidene Complexes with Hydrophosphoryl Compounds

We studied the reactions of manganese and rhenium phenylvinylidenes Cp­(CO)₂MCC­(H)­Ph (<b>Mn1</b> M = Mn; <b>Re1</b> M = Re) with HP­(O)­R₂ (R = C₆F₅, Ph, and OEt) and HP­(S)­Ph₂, which resulted in the selective formation of η²-<i>E</i>-phosphorylalkene complexes Cp­(CO)₂M­{η²-<i>E</i>-H­[R₂(O)­P]­CC­(H)­Ph} (<b>Mn2</b>, <b>Re2</b> R = C₆F₅; <b>Mn3</b>, <b>Re3</b> R = Ph; and <b>Mn6</b>, <b>Re6</b> R = OEt) and Cp­(CO)₂M­{η²-<i>E</i>-H­[Ph₂(S)­P]­CC­(H)­Ph} (<b>Mn5</b>, <b>Re5</b>). The DFT/B3LYP­(6-31G*) analysis showed the model reactions of <b>Mn1</b> with HP­(O)­Me₂ and HP­(O) (OMe)₂ to proceed via the initial transition state Cp­(CO)₂{Ph­(H)­CC}­Mn···HO–PR₂ (<b>TS1</b>) where the minor <b>PA</b> form HO–PR₂ is hydrogen-bonded to the metal, followed by stereoselective (<i>trans</i>- to the phenyl group) addition of the <b>PA</b> phosphorus atom to the C_α-vinylidene atom, which defines both the rate of the process and the anti-Markovnikov structure of the reaction product. The reactions can proceed at a relatively low content of the reactive <b>PA</b> form