Two crystal structures of copper(II) complexes and adducts based on the neutral N1,N1-dimethyl-N2-(pyridin-2-ylmeth­yl)ethane-1,2-di­amine ligand

Abstract

Two crystal structures of copper(II) complexes with a tridentate ligand are reported, new [Cu(N^N^N)(H₂O)Cl][Cu(N^N^N)Cl₂][CuCl₄] and already known [Cu(N^N^N)(NCS)₂]·0.3 H₂O, (N^N^N = N¹,N¹-dimethyl-N²-(pyridin-2-ylmeth­yl)ethane-1,2-di­amine), which exhibit a considerable range of inter­molecular inter­actions and notable packing patterns that are being discussed.

From the reaction of copper(II) chloride dihydrate with N¹,N¹-dimethyl-N²-(pyridin-2-ylmeth­yl)ethane-1,2-di­amine (denoted N^N^N) a new species comprising three distinct complexes crystallized, namely, aqua­chlorido­[N¹,N¹-dimethyl-N²-(pyridin-2-ylmeth­yl)ethane-1,2-di­amine-κ³N,N′,N′′]copper(II)chlorido­[N¹,N¹-dimethyl-N²-(pyridin-2-ylmeth­yl)ethane-1,2-di­amine-κ³N,N′,N′′]copper(II) tetra­chlorido­cuprate(II), [CuCl(C₁₀H₁₇N₃)(H₂O)][CuCl(C₁₀H₁₇N₃)][CuCl₄] or [Cu(N^N^N)(H₂O)Cl][Cu(N^N^N)Cl₂][CuCl₄], the latter two of which form an adduct. This complex was reacted with ammonium thio­cyanate to form [Cu(N^N^N)(NCS)₂], which crystallized with two independent mol­ecules and a partial water in the asymmetric unit very similarly to the already reported structure of this compound. Both crystal structures show a rather complex set of inter­molecular inter­actions including hydrogen bonding and what may be described as chalcogen bonding, pnictogen bonding and/or coinage bonding. The mol­ecular structures, intra­molecular inter­actions and packing patterns are discussed in detail and the more unusual ones are set into the context of structures available in the literature.