(12,17-diethoxycarbonyl-11,18-dimethyl-2,3:6,7-dibutanocorrphycenato) copper(II)-12,17-diethoxycarbonyl-11,18-dimethyl-2:3,6:7-dibutanocorrphycene(3/ 97)

The corrphycene molecule of the title compound, [Cu(C ₃₆H _36- N ₄O ₄)] _0.034.0.966C ₃₆H ₃₈N ₄O ₄, has an essentially planar macrocyclic framwork with a slightly distorted trapezoidal N ₄ core; the r.m.s. deviation of the peripheral 20 C atoms and four N atoms is 0.054(3) Å. The surface area within the N ₄ ^- coordinating core (8.358 Å ²) is significantly smaller than that (8.503 Å ²) of the corresponding free-base porphyrin. Two intramolecular N-H··· N hydrogen bonds are observed. Detailed structure analysis clarified that the co-crystallization of the free-base corrphycene together with a quite minor component (ca 3%) of corrphycenato-Cu ^II occurred in the recrystallization process.