| Abstract: | Polyol Metal Complexes.471) Crystalline D ‐Mannose‐Copper Complexes from Fehling Solutions Blue, unstable crystals of K3Cu5(β‐D ‐Manp)4H—13] · α‐D ‐Manp · 16.5 H2O ( 1 ), which contain a pentanuclear cupric complex of the reducing sugar D ‐mannose in its β‐pyranose form (β‐D ‐Manp), have been obtained from ice‐cold aqueous alkaline solutions. The homoleptic pentacuprate contains bridging mannopyranose ligands, which are charged 4— and 2.5—. Addition of ethylenediamine (en) to such Fehling solutions yields N, N′‐Bis(β‐D ‐mannopyranosyl)‐ethylenediamine (L) as a condensation product of the diamine and mannopyranose. Crystals of (en)2Cu7(β‐D ‐Manp1, 2, 3, 4H—4)2(L2, 3, 4H—3)2] · 26.6 H2O ( 2 ) could be isolated. The heptanuclear cupric complex is a structural derivative of the homoleptic mannose complex. |
