Structural consequences of the prohibition of hydrogen bonding in copper-guanidine systems.
The synthesis and structure of copper(I) complexes supported by N-substituted bicyclic guanidines is described. The N-methyl-substituted bicyclic guanidine 1,3,4,6,7,8-hexahydro-1-methyl-2H-pyrimido[1,2-a]pyrimidine (hppMe) reacted with copper(I) chloride to afford the ion-pair [Cu(hppMe)(2)][CuCl(2)] (1), a rare example of a compound containing an unsupported Cu...Cu interaction. The analogous reaction with CuI, however, afforded the molecular mu,mu-dihalo-bridged dimer [CuI(hppMe)](2) (2). Inclusion of a trimethylsilyl substituent at nitrogen provided a sufficiently sterically encumbered environment to support a two coordinate copper center in CuCl(hppSiMe(3)) (3). Compounds 1-3 have been fully characterized, including single-crystal X-ray diffraction studies.
Department of Chemistry, University of Sussex, Falmer, Brighton BN1 9QJ, U.K.
Sarah H
SH
Oakley
Martyn P
MP
Coles
Peter B
PB
Hitchcock
D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D019791:Guanidine / Q000737:chemistry*; D006860:Hydrogen Bonding; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D012821:Silanes / Q000138:chemical synthesis / Q000737:chemistry
D008024:Ligands; D009942:Organometallic Compounds; D012821:Silanes; D003300:Copper; D019791:Guanidine