Self-assembled xanthate-transition metal polyether macrocycles and cryptands Paul D. Beer a, *, Andrew R. Cowley b , John C. Jeffery c , Rowena L. Paul a , Wallace W.H. Wong a a Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK b Chemical Crystallography Laboratory, 9 Parks Road, Oxford, OX1 3PD, UK c School of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, UK Received 6 August 2002; accepted 9 October 2002 Abstract The synthesis of novel dinuclear nickel(II) /xanthate polyether macrocycles and dinuclear cobalt(III)  /xanthate polyether cryptands is reported. The assemblies have been characterised by a range of spectroscopic techniques and in one case by X-ray crystal structure determination. Electrospray mass spectrometry provided evidence that the dinuclear nickel(II)  /xanthate macrocycles form adducts with Group I metal cations and methyl viologen (MV 2 ). The dinuclear cobalt(III) /xanthate cryptands also form adducts with Group I metal cations but did not interact with MV 2 . # 2003 Elsevier Science Ltd. All rights reserved. Keywords: Cryptands; Polyether macrocycles; Xanthate; Methyl viologen 1. Introduction The synthesis of two- and three-dimensional macro- cyclic and cage-like host molecules using metal directed self-assembly is a current area of intense research activity [1]. Through prudent choice of metal ion and multidentate ligand components, the resulting self- assembled polymetallic structures can be designed to exhibit unique electronic and magnetic properties, and have the potential to bind guest substrates [1,2]. Presently the field is dominated by square planar platinum(II) metals in combination with various oligo- pyridine ligands, [1c,3] copper(I), nickel(II), silver(I), iron(II) helical structures of oligobipyridyls [3] and pseudo-octahedral titanium(IV), aluminium(III), iro- n(III), gallium(III) complexes of oligocatecholate li- gands leading to triple helicates [3] and tetrahedral clusters [4]. Using the dithiocarbamate ligand as a self- assembling structural motif for the first time, we have recently synthesised novel nano-sized resorcarene-based transition metal polymetallic assemblies [5] which bind C 60 [6] and copper(II)  /dithiocarbamate macrocycles capable of selectively sensing anionic guest species using electrochemical techniques [7]. This paper describes the synthesis of novel dinuclear macrocycles and cryptands based on metal  /xanthate ligand interactions. The co- ordination chemistry of the xanthate (dithiocarbonate) ligand is well established, [8] however, to our knowledge this ligand has not been exploited in the field of metal directed self-assembly. We report here the incorporation of the xanthate ligand into various polyether linkages, and by using metal directed self-assembly, the synthesis of new dinuclear nickel(II)  /xanthate polyether macro- cycles and dinuclear cobalt(III)  /xanthate polyether cryptands. 2. Results and discussion 2.1. Syntheses The polyether bis-xanthate salts were prepared in almost quantitative yields via reaction of the appro- * Corresponding author. Tel.:  /44-1865-272632; fax:  /44-1865- 272690. E-mail address: paul.beer@chem.ox.uk (P.D. Beer). Polyhedron 22 (2003) 795  /801 www.elsevier.com/locate/poly 0277-5387/03/$ - see front matter # 2003 Elsevier Science Ltd. All rights reserved. doi:10.1016/S0277-5387(02)01412-2