The Oxidation of Citric Acid

Abstract

Although the analytical evidence indicated that CssHsoCh was a diketone, no derivatives of the carbonyl group were obtained. Furthermore, the reduction product did not give reactions of the hydroxyl group although four atoms of hydrogen were apparently added to the diketone. Summary 1. The polyine, tetraphenyl-di-(3-methyl-3-ethylpentinyl-l)-ethane has been prepared. It is oxidized by air, cleaved by 40% sodium amalgam, and rearranges spontaneously to give a more stable isomeric hydrocarbon, C42H46• 2. Some reactions of the rearranged hydrocarbon C42H46 have been studied in the hope of establishing its structure. Cleavage by sodium amalgam has furnished evidence that at least half of the molecule retains the original carbon skeleton.3. The question of final structure of the isomeric hydrocarbon C42H46 and the exact nature of the rearrangement by which it is formed must be left open until further evidence can be obtained.

One-pot hydrothermal synthesis of silver nanowires via citrate reduction

“…After the hydrothermal reaction, the system transformed from colorless transparent solution to grey-colored suspension, indicating the formation of Ag particles. The overall reaction can be described by the following equation [51]: chemicals were added). At low magnification (Fig.…”

Second harmonic generation response by gold nanoparticles at the polarized water/2-octanone interface: from dispersed to aggregated particles

“…The SH signal intensity exhibits a clear increase as w o φ is made more negative. Considering that the citrate-stabilized gold nanoparticles carry a net negative charge as a result of the citrate reduction preparation [17,18], this signal increase results from an increase in the number density of gold particles at the interface, provided that the hyperpolarizability is unchanged. The fact that the SHG signal is monotonous over the potential range explored indicates that the hyperpolarizability is indeed insensitive to the externally applied potential, since the applied field changes sign over this range.…”

Monodisperse sub-10nm gold nanoparticles by reversing the order of addition in Turkevich method – The role of chloroauric acid

“…Acetone dicarboxylic acid is a product of citrate oxidation that facilitates nucleation by acting as an organizer [18,19,48], thereby, eliminating the induction period for particle formation. Thermal oxidation of citrate by dissolved oxygen [49] at boiling conditions to form acetone dicarboxylic acid could plausibly explain the results obtained upon reversing the order of addition. To verify this, the following experiments were carried out at MR 20.8: (a) citrate solution was brought to boil for 10 min prior to its addition to chloroauric acid solution, (b) 23.75 mL of water was boiled and 0.25 mL of chloroauric acid was added followed by 1 mL of sodium citrate after 10 s (vide infra), and (c) 23.75 mL of water was brought to boil and 1 mL of citrate was added followed by 0.25 mL of chloroauric acid solution after 10 s. The particle size and reaction time ( Fig.…”