Chromium complexes of three new ligands, Ph2PN(Me)(CH2)2-X [X = NMe2(PNN); PPh2 (PNP); Py (PNPy)], have been examined vis-à-vis their ability to promote ethylenetetramerization, (PNN)CrCl3(L) [L = THF (1); CH3CN (2)], (PNPy)CrCl3(L) [L = THF (3); CH3CN (4)], and (PNP)CrCl3(THF) (5). In the case of 2 and 4, it was possible to grow crystals suitable for X-ray diffraction. The reaction of 3 with Et3Al