Crystal structure of a supra­molecular lithium complex of p-tert-butyl­calix[4]arene

Crystals of a supra­molecular lithium complex with a calix[4]arene derivative, namely tetra­methano­llithium 5,11,17,23-tetra-tert-butyl-25,26,27-trihy­droxy-28-oxidocalix[4]arene methanol monosolvate, [Li(CH3OH)4](C44H55O4)·CH3OH or [Li(CH3OH)4]+·(calix[4]arene−)]·CH3OH (where calix[4]arene− represents a mono-anion species because of deprotonation of one H atom of the calixarene hy­droxy groups), were obtained from p-tert-butyl­calix[4]arene reacted with LiH in tetra­hydro­furan, followed by recrystallization from methanol. The asymmetric unit comprises one mono-anionic calixarene mol­ecule, one Li+ cation coordinated to four methanol mol­ecules, and one methanol mol­ecule included in the calixarene cavity. The calixarene mol­ecule maintains a cone conformation by intra­molecular hydrogen bonding between one phenoxide (–O−) and three pendent calixarene hy­droxy groups (–OH). The coordinated methanol mol­ecules around the metal cation play a significant role in forming the supra­molecular assembly. The crystal structure of this assembly is stabilized by three sets of inter­molecular inter­actions: (i) hydrogen bonds involving the –OH and –O− moieties of the calixarene mol­ecules, the –OH groups of the coordinated methanol mol­ecules, and the –OH group of the methanol mol­ecule included in the calixarene cavity; (ii) C—H⋯π inter­actions between the calixarene mol­ecules and/or the coordinated methanol mol­ecules; (iii) O—H⋯π inter­actions between the calixarene mol­ecule and the included methanol mol­ecule.