A series of self-assembled monolayers (SAMs) formed on Au(111) from partially fluorinated alkanethiols (PFAT) with variable length of the fluorocarbon chain, viz. F(CF 2 ) n (CH 2 ) 11 SH (FnH11SH, n = 6, 8, and 10), was studied by high resolution X-ray photoelectron spectroscopy, infrared reflection absorption spectroscopy, and near edge X-ray absorption fine structure spectroscopy. The SAMs were found to be highly ordered and densely packed. The packing density was governed by the bulky fluorocarbon segments which adopted a helical conformation typical of this entity. With decreasing length of the fluorocarbon segment, progressive deterioration of the orientational order accompanied by a slight decrease in the packing density was observed in the fluorocarbon part of the FnH11SH SAMs. The conformation of the fluorocarbon segment was persistent through the series, with probably only a minor deterioration for n = 8 and 6. The hydrocarbon segments of the monolayers were, however, unaffected by the deterioration of the orientational order in the fluorocarbon part. They persistently exhibited all trans planar conformation, typical of densely packed assemblies of these moieties, while their orientation, given by the characteristic tilt and twist angles, mimicked that of the nonsubstituted alkanethiolate SAMs on Au(111). This behavior is explained by the effect of the bending potential which predefines the orientation of the hydrocarbon segments even if they are separated beyond the equilibrium spacing by the bulky fluorocarbon moieties.

The reaction of methyl‐4,6‐O‐(naphthyl‐2′‐methylidene)‐α‐D‐glucopyranoside (α‐MeNGH2) with trichloridopentamethylcyclopentadienyltitanium [Cp*TiCl3] and triethylamine in toluene reveals the dinuclear complex [(Cp*TiCl)‐μ‐(α‐MeNG)]2 (2). Complex 2 was characterized by elemental analysis, 1H and 13C NMR spectroscopy, circular dichroism, as well as single‐crystal structure analysis. Compared to the complex with the β‐anomer of the ligand in [(Cp*TiCl)‐μ‐(β‐MeNG)]2 (1), it is obvious that the absolute configuration of the Ti atoms in 2 have changed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Despite their advantageous properties, monosaccharide-derived ligands have rarely been applied in the synthesis of organometallic compounds and thus little is known about their coordination capabilities. Most of the established monosaccharide-metal complexes are based on late transition metals such as Rh, Pd and Pt [1]. Among early transition metals, monosaccharide complexes containing Ti and Zr are of importance [2]. Although the information pertaining to their metal-ligand binding sites is scarce, both late and early transition metal complexes of modified monosaccharides have been successfully applied as chiral reagents and catalysts in stereoselective synthesis [3]. Synthesis of Organotitanium Carbohydrate CompoundsWithin this research topic we are interested in the ability of pyranosides to coordinate to varying titanium precursors and the use of the resulting complexes in stereoselective synthesis. In particular we are investigating the 2-and 3-positions of pyranosides as coordination sites for organometallic complexes of the early transition metal Ti. The torsion angle between the oxygen functions of C2 and C3 of the pyranosidato ligand may determine whether a mononuclear chelate complex or a dinuclear compound with a bridging coordination between two Ti atoms is formed.Our interest in the coordination chemistry of Ti when reacted with carbohydrate ligands has led to previously reported reactions [4,5]. The reaction of methyl-4,6-Obenzylidene-b-D-glucopyranoside (b-MeBnGluH 2 ) with the organotitanium complex Cp à TiCl 3 in the presence of triethylamine gave the dinuclear titanium complex (T-4-R; T-4-R)bis[chlorido(h 5 -pentamethylcyclopentadienyl)][m-(methyl-4,6-O-benzylidene-b-D-glucopyranosidato-1kO 2 , 2kO 3 )][m-(methyl-4,6-O-benzylidene-b-D-glucopyranosiActivating Unreactive Substrates: The Role of Secondary Interactions. Edited

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