An attempt to synthesize a complex between copper(I) cyanide and thioacetamide (ta) by a direct combination in aqueous solution, surprisingly, produced instead Cu-4(S2O3)(2)(ta)(10). ta (1), a complex lacking cyanide but including thiosulfate. We know of no precedent for the production of thiosulfate from an aqueous solution of ta. Using a new synthetic approach, a complex of CuCN and ta was subsequently prepared-(CuCN)(ta), 2. In the new method, which has been found to be widely applicable to water-soluble ligands, CuCN is made "available" for coordination by dissolving it in aqueous sodium thiosulfate. Complex 1 crystallizes in the triclinic space group <(P)over bar 1> (No. 2) with unit cell dimensions a 10.139(3) Angstrom, b = 12.230(4) Angstrom, c = 12.665(4) Angstrom, alpha 85.20(2)degrees, beta 67.32(2)degrees, gamma = 68.47(2)degrees, V = 1345(2) Angstrom(3), and Z = 2. Complex 2 crystallizes in the orthorhombic space group Pna2(1) (No. 33) with unit cell dimensions a = 6.993(9) Angstrom, b = 8.744(3) Angstrom, c = 9.372(6) Angstrom, V = 573(1) Angstrom(3), and Z = 4. Some possible pathways for the production of thiosulfate are discussed.