Hydridic Rhenium Nitrosyl Complexes with Pincer-Type PNP Ligands

The hydride complexes ReHBr(NO)[HN(C2H4PR2)2] (R = Pri, 1a; But, 1b) were synthesized by reactions
of [NEt4]2[Re(NO)Br5] with the pincer-type ligands HN(C2H4PR2)2. Treatment of 1a and 1b with ButOK
led to their dehydrobromination, resulting in the amido hydrides ReH(NO)[N(C2H4PR2)2] (2a,b),
respectively. The dihydride trans-ReH2(NO)[HN(C2H4PPri2)2] (3a) was obtained by stirring an ether
solution of 2a under hydrogen. Similarly, partial conversion of 2b was achieved under hydrogen to give
trans-ReH2(NO)[HN(C2H4PBut2)2] (3b). The structure and properties of complexes 1−3 were studied by
DFT calculations. Complexes 2a and 3a demonstrated low activity for transfer hydrogenation of
acetophenone and cyclohexanone due to instability in 2-propanol.