In this study we have broadened the family of azophosphines 1-R by systematically varying the electronic nature of the N-aryl substituent. The changes in electronics yield clear trends in the NMR and UV-Vis spectroscopic measurements of these compounds, and also has a minor effect on the structure of the azophosphines as explored by single crystal X-ray diffraction and DFT studies. The azophosphine-selenides 3-R were synthesised and the 1 JP-Se coupling constant measured to assess the donor strength of the phosphine centre; these results showed that azophosphines in general are relatively weaker phosphine donors, but that the strength can be fine-tuned with the more electron-donating N-aryl substituents giving stronger azophosphine donors. This finding was also borne out in the coordination chemistry studies, where the stronger donors afforded the bidentate [Ru(p-cymene)(κ 2 P,N-(1-R))Cl][BPh4] (5-R) complexes more cleanly. Finally, we explored the Ru complexes 4-OMe and 5-OMe as catalysts in the transfer hydrogenation of acetophenone. Both catalysts could promote this transformation without the need for harsh external bases, and the bidentate complex 5-OMe was a much more efficient catalyst. These results show that azophosphines are valuable hybrid ligands that can be readily tuned and can promote important catalytic reactions. Work to explore the role of azophosphines and related ligands in catalysis is on-going in our laboratory.