in benzene-d6 byproducts: ((CH3)3C6H2)2C2N2H2PBr; dissolution of Mes2C2N2H2PC5H5 and Mn(CO)5Br in C6D6 under Ar; not isolated, NMR anal.;

in benzene-d6 byproducts: ((CH3)3C6H2)2C2N2H2PCl; dissolution of FeCl2 and Mes2C2N2H2PC5H5 in C6D6 under Ar; not isolated, NMR anal.;