Crystal structure of a host–guest complex between mephedrone hydro­chloride and a tetra­phospho­nate cavitand

A new supra­molecular complex (I) between the tetra­phospho­nate cavitand Tiiii[C(3)H(7),CH(3),C(6)H(5)] [systematic name: 2,8,14,20-tetra­propyl-5,11,17,23-tetra­methyl-6,10:12,16:18,22:24,4-tetra­kis­(phenyl­phospho­nato-O,O′)resorcin[4]arene] and mephedrone hydro­choride {C(11)H(16)NO(+)·Cl(−); systematic name: meth­yl[1-(4-methyl­phen­yl)-1-oxopropan-2-yl]aza­nium chloride} has been obtained and characterized both in solution and in the solid state. The complex of general formula (C(11)H(16)NO)@Tiiii[C(3)H(7),CH(3),C(6)H(5)]Cl·CH(3)OH or C(11)H(16)NO(+)·Cl(−)·C(68)H(68)O(12)P(4)·CH(3)OH, crystallizes in the monoclinic space group P2(1)/c with one lattice methanol mol­ecule per cavitand, disordered over two positions with occupancy factors of 0.665 (6) and 0.335 (6). The mephedrone guest inter­acts with the P=O groups at the upper rim of the cavitand through two charge-assisted N—H⋯O hydrogen bonds, while the methyl group directly bound to the amino moiety is stabilized inside the π basic cavity via cation⋯π inter­actions. The chloride counter-anion is located between the alkyl legs of the cavitand, forming C—H⋯Cl inter­actions with the aromatic and methyl­enic H atoms of the lower rim. The chloride anion is also responsible for the formation of a supra­molecular chain along the b-axis direction through C—H⋯Cl inter­actions involving the phenyl substituent of one phospho­nate group. C—H⋯O and C—H⋯π inter­actions between the guest and adjacent cavitands contribute to the formation of the crystal structure.