Crystal structure of sparteinium tetrachlorocuprate monohydrate-packing polymorph

A new polymorph of sparteinium tetrachlorocuprate monohydrate [(C₁₅H₂₈N₂)CuCl₄·H₂O] is reported. The structure of the analyzed crystal was solved in the orthorhombic P2₁2₁2₁ space group with the following unit cell parameters at 295 K: a = 9.7722(2) Å; b = 13.4582(3) Å; c = 15.1582(3) Å. The various types of hydrogen bonding interactions existing in the crystal structure of this salt were compared with the data of the previously reported polymorph. XRPD measurement proved that our salt consists of a pure phase of the new polymorph. Cooling down the salt to ca. 230 K caused its color to change from orange-brown to yellow. DSC experiments revealed that during the cooling an endothermic process takes place corresponding to the mentioned color change of the salt. Graphical abstract:

.