This paper reports the synthesis, structure, and properties of a series of PNP pincer complexes of osmium OsH3Cl[HN(C2H4PiPr2)2] (1), OsH3[N(C2H4PiPr2)2] (2), OsH4[HN(C2H4PiPr2)2] (3), and OsH2(PMe3)[HN(C2H4PiPr2)2] (4). The tetrahydride 3operates as an efficient catalyst at 0.1 mol% loading for the reactions of amination and dehydrogenative coupling of primary alcohols, producing secondary amines and symmetrical esters, respectively. The catalyst 3is distinguished by outstanding stability, and it can be used in an aqueous environment at temperatures as high as 200 °C. [ABSTRACT FROM AUTHOR]