Abstract : The phosphinine, the phosphorus analog of the pyridine, features strong pi-accepting properties. Thus they are very good ligands for stabilisation of electron rich complexes. This peculiar caracteristic is the backbone of the PhD thesis presented here. It seemed indeed interesting to study in details the behaviour of the phosphinine towards reduction in a broad sense, which means electron supply, but also attack with an electron rich group like a nucleophile. Three axes of study have been followed: the electronic reduction of phosphinine containing molecules, the nucleophilic addition on the phosphinine and the use of phosphinine as ligand for gold nanoparticles. The first part of this work deals with phosphinine reduction and related works on other molecules (containing or not phosphorus atoms). Species containing bonding interactions with an incomplete number of electrons were synthetised and characterised. Then, electron rich complexes of biphosphinine and diphosphabutadiene were studied from a theoretical and experimental point of view. Secondly, results obtained on phosphinine anion chemistry are presented. We studied their coordination chemistry and isolated complexes of eta2 or eta5 type. These anions were also exploited for synthesis of the first phosphininium cation known to date. Eventually, the phosphinine was used for gold nanoparticles stabilisation. Particles thus obtained feature original properties utilised for sensing application or for the synthesis of Janus type nanoparticles.