A methanolic solution of Cu(OAc)2.H2O (0.199 g, 1 mmol) was
added to a methanol solution of Heptu (1.038 g, 2 mmol) with continuous
stirring for 30 min. The resulting solution was filtered and
the filtrate was kept for 5 days, whereupon orange crystals of complex 2 suitable for X-ray structural investigation were obtained.