title: Copper thiocyanato complexes and cocaine - a case of 'black cocaine'.
abstract: The chemical composition of a black powder confiscated by German customs was elucidated. Black powders are occasionally used as a 'transporter' for cocaine and are obviously especially designed to cloak the presence of the drug. The material consisting of cocaine, copper, iron, thiocyanate, and graphite was approached by analytical tools and chemical modelling. Graphite is added to the material probably with the intention of masking the typical infrared (IR) fingerprints of cocaine and can be clearly detected by powder X-ray diffraction (XRD) and Raman spectroscopy. Cu(2+) and NCS(-) ions, when carefully reacted with cocaine hydrochloride, form the novel compound (CocH)2 [Cu(NCS)4 ] (CocH(+)  = protonated cocaine), which has been characterised by single crystal XRD, IR, NMR, UV/Vis absorption and EPR spectroscopy. Based on some further experiments the assumed composition of the original black powder is discussed.
authors.affiliation: Centre of Education and Science of the Federal Revenue Administration, D-50765 Köln, Germany.
authors.forename: Tim
authors.initials: T
authors.lastname: Laussmann
authors.forename: Ireneus
authors.initials: I
authors.lastname: Grzesiak
authors.forename: Alexander
authors.initials: A
authors.lastname: Krest
authors.forename: Kathrin
authors.initials: K
authors.lastname: Stirnat
authors.forename: Sigrid
authors.initials: S
authors.lastname: Meier-Giebing
authors.forename: Uwe
authors.initials: U
authors.lastname: Ruschewitz
authors.forename: Axel
authors.initials: A
authors.lastname: Klein
mesh_terms: D003042:Cocaine / Q000032:analysis*; D056831:Coordination Complexes / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004578:Electron Spin Resonance Spectroscopy; D006108:Graphite / Q000737:chemistry; D013287:Illicit Drugs / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D033362:Powder Diffraction; D011208:Powders; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013861:Thiocyanates / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D056831:Coordination Complexes; D013287:Illicit Drugs; D011208:Powders; D013861:Thiocyanates; D006108:Graphite; D003300:Copper; D003042:Cocaine; C031760:thiocyanate
keywords: cocaine; copper; iron; masking; powder XRD; thiocyanate