Tuning peripheral π-stacking motifs in {Cr(tpy)2}3 + domains (tpy = 2,2′:6′,2″-terpyridine)

• Stepwise synthesis of homoleptic [Cr(4′-X-tpy)2]3 + complex
• Introduction of 4′-naphth-2-yl domains and impact on packing interactions
• X-ray crystal structures of isostructural [Cr(4′-(naphth-2-yl)-tpy)2][PF6]3 and [Co(4′-(naphth-2-yl)-tpy)2][PF6]3 complexes

The homoleptic complexes [Cr(1)2][PF6]3 and [Co(1)2][PF6]3 (1 = 4′-(naphth-2-yl)-2,2′:6′,2″-terpyridine) have been prepared and structurally characterized. The packing interactions in both complexes are identical, consisting of a combination of naphthyl…naphthyl π-stacking interactions and double naphthyl…pyridine embraces generating chains of cations with alternating long and short M…M contacts.

In the solid state, the isostructural complexes [Cr(1)2][PF6]3 and [Co(1)2][PF6]3 (1 = 4′-(naphth-2-yl)-2,2′:6′,2″-terpyridine) exhibit packing interactions which combine naphthyl…naphthyl π-stacking interactions and double naphthyl…pyridine embraces generating chains of cations with alternating long and short M…M contacts.Figure optionsDownload as PowerPoint slide