A convenient synthesis of long-chain 4-substituted benzyloxycarbonyl alkanethiols for the formation of self assembled monolayers on metal substrates

Abstract

New 4-substituted benzyl esters of 16-mercaptohexadecanoic acid were prepared by developing a practicable synthetic procedure and using readily available starting materials. The compounds synthesized have been characterized by NMR, MS, IR spectra and elemental analysis. The mercapto derivatives are precursors for the formation of self-assembled monolayers on metal substrates.

Formation of N-acylureas on the surface of TEMPO-oxidized cellulose nanofibril with carbodiimide in DMF

“…The weight recovery ratio was [97%, and most of the recovery loss was caused by repeated washing and purification processes using centrifugation. The absorption band around 1,720 cm -1 due to stretching vibration of free carboxyl C=O groups mostly disappeared, and new bands at 1,698, 1,658 and 1,536 cm -1 due to C=ON, C=ONH and N-HCO groups, respectively, (DeTer and Silverstein 1965;Angelova et al 2005;Buchanan et al 2007) appeared for the reaction product. The bands at 2,750-3,000 cm -1 were ascribed to C-H stretching vibration of isopropyl groups.…”

“…3. Although a small signal around 175 ppm due to carboxyl carbons of TOCN-COOH remained after the reaction, two new signals at 155 and 169 ppm due to two carbonyl carbons of Nacylurea groups appeared in the spectrum of the reaction product (Angelova et al 2005;Buchanan et al 2007). The signals in the range of 20-50 ppm were ascribed to -CH 3 and -CH carbons of isopropyl moiety of the N-acylurea groups.…”

“…Because the reaction product was washed thoroughly with 0.01 M HCl, it was not plausible that carboxyl groups of TOC formed ammonium salts with DIC-derived compounds. On the other hand, it is likely from the FT-IR spectrum that the reaction product had N-acylurea groups, which are possible to be formed from carboxyl groups by reaction with carbodiimide and stably present in the product (DeTer and Silverstein 1965; Angelova et al 2005;Buchanan et al 2007).…”

Orientation Analysis of ω-Substituted Long-Chain Alkanethiols Self-Assembled on Au Substrate

“…The synthesis of model compounds 1 and 2 (Figure ) has been published previously . Gold substrates (200 nm gold with a titanium intermediate layer on glass) were purchased from Ssens (The Netherlands).…”

Thiol modified mycolic acids

“…This is typical for the carbon adjacent to sulfur in sulfides. [Anklam, 1990;Thuo, 2011;Angelova, 2005] Scheme 5: (i) excess diazomethane; (ii) acetic anhydride, pyridine, toluene; (iii) DL-dithiothreitol In the same way, the disulfide could be split to free thiol (30) without protection of the alcohol and acid groups. The 1 H NMR spectrum of this again showed a quartet at δ 2.52 for the methylene group adjacent to sulphur.…”