Dodecane thiols

These are oxidised by both Fe(III) and Cu(II) octanoates (denoted Oct) in nonpolar solvents at moderate temperatures . 80-90 % yields of the corresponding disulphide are obtained with Fe(III) and this oxidant was selected for kinetic study, the pattern of products with Cu(II) being more complex. The radical nature of the reaction was confirmed by trapping of the thiyi radicals with added olefins. Simple second-order kinetics were observed, for example, with l-dodecane thiol oxidation by Fe(Oct)3 in xylene at 55 °C (fcj = 0.24 l.mole . sec ). Reaction proceeds much more rapidly in more polar solvents such as dimethylformamide. The course of the oxidation is almost certainly... 

Figure 5.2 STM images ofthiols SAM on Au/mica illustrating the range of structural qualities, (a) high-quality SAM of dodecane thiol prepared from a solution of dodecane thiocyanate [111] and a low-quality aromatic SAM of methylbiphenyl butane thiol (MBP4) (b) [90].

Typical procedure A solution of (dodecane thiol, = Me(CH2) , 1 mL, 4.17 nunol), trimethyl phosphite (591 pL, 5.01 mmol) and terf-amine (lutidine 681 pL, 5.84 nunol) or calcium carbonate (1.4 mol equiv based on the thiol) in CH2CI2 (20 mL) was cooled to -42°C in an MeCN-solid CO2 bath, and TeCl4 (0.8 equiv) was added. The mixture was stirred at the same temperature for 5-10 min and then, after removal of the bath, stirring was continued at room temperature (1.5-3 h). Precipitates were filtered off and the filtrate was washed with water and dried (MgS04). The solvent was removed under reduced pressure and the phos-phorothioate (1.24 g, 96% yield) were isolated by column chromatography on silica gel. 

The ethers are formed by a Williamson ether synthesis (ROH, NaOH, DMF, 3 h, 70-93% yield) and are cleaved by photolysis at 350 nm in the presence of the radical scavengers sorbitol or dodecane thiol (IPA, 30-1440 min, 25-93% yield. ... 

Functionalization of nanorods with polyelectrolytes has been carried out by layer-by-layer deposition (92). First, CTAB-coated nanorods are prepared. Since these nanorods are positively charged, they can adsorb cationic and anionic poly electrolytes. Functionalization of nanorods with dyes is possible a fluorescent dye, 4-chloro-7-nitrobenzofurazan has been functionalized on the surface of Ti02 nanorods (93). Functionalization with a photoactive molecule such as ruthenium(II) tris(bipyridine) is also possible (94). A thiol derivative of the bipyridyl complex (Ru(bpy)3+-Cs-SH) in dodecane thiol is used for the functionalization of gold nanorods. Functionalization of block magnetic nanorods is very useful (95), for example, in the separation of proteins. Consider a triblock nanorod consisting of only two metals, Ni and Au. If the Au blocks are functionalized with a thiol (e.g. 11-amino-1 undecane thiol) followed by covalent attachment of nitrostreptavidin, then one can... 

Fig. 3 (A) Mass spectra of the crude mixture (a) and of isolated fractions (b-e) of dodecane thiol protected gold clusters. Inset shows the structures predicted from optimal cores of N = 459, 314, etc. gold atoms. Wiley-VCH publishing. Reproduced with permission. (B) Low resolution ESI mass spectra of the isolated clusters (1-9). (C) The high resolution spectra of the same. The trace shows the corresponding calculated spectra for AUn(SG)m clusters with the corresponding n-m values. ACS publishing. Reproduced with permission. ...

Minor peaks in the chromatogram were associated with end groups derived from benzoyl peroxide polymerisation initiator or dodecane thiol chain transfer agent reactions. End-group data were related to molecular weight data. 

Yamamoto, S. and H. Watarai, Surface-enhanced Raman spectroscopy of dodecane-thiol-bound silver nanoparticles at the liquid/liquid interface, Langmuir, Vol. 22,... 

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