Anions acetate

Asymmetric Heck reaction of the conjugated diene 184 and subsequent acetate anion capture of the rr-allylpalladium intermediate afforded 185 in 80% ee. which was converted into the key intermediate 186 for the capnelle-... 

The intramolecular insertion of a conjugated diene into 7r-allylpalladium, initially formed in 789, generates another rr-allyl complex 790, which is trapped with acetate anion to give a new allylic acetate 791. No further reaction of the allylic acetate with alkene takes place[489]. 

Electrostatic potential map for acetate anion shows most negatively-charged regions (in red) and less negatively-charged regions (in blue). 

The platinum electrode was modified with an iodine adlayer of the specified symmetry. ) AC = acetate anion. 

Example applies the composite model of bonding to the acetate anion. 

The acetate anion (CH3 CO2 ) forms when acetic acid, the acid present in vinegar, is treated with hydroxide ion CH3 CO2 H -1- OH" -> CH3 CO2 + H2 O Use the four guidelines of the composite model of bonding to describe the bonding of this anion. Sketch the a bonding system and the occupied 7t... 

The acetate anion has 24 valence electrons, leading to a Lewis structure with two resonance forms ... 

In the acetate anion, the two oxygen atoms are equivalent, so we expect that the orbital descriptions about each O atom should be identical. You can verily that they are, and experiments further verily this the two carbon-oxygen bond lengths in acetate are identical. 

As one example, dissolving sodium acetate in a solution of acetic acid produces a buffer solution in which both acetic acid and acetate anions are major species. Example describes an acetic acid-acetate buffer solution. 

The original solution contains water and acetic acid molecules. Adding sodium acetate introduces two new major species, acetate anions and sodium cations. Thus, the resulting buffer solution has four major species H2 O, Na , CH3 CO2, and CH3 CO2 H. 

Acetic acid is a weak acid, acetate anion is a weak base, water can act as an acid or a base, and Na+ is a spectator ion. These species are reactants in three acid-base equilibria ... 

A third approach to buffer solutions is to add strong acid to a solution of a weak base. This produces a buffer solution if the amount of strong acid is about half the amount of weak base. Continuing with our examples of acetic acid-acetate buffers, if a solution of hydrochloric acid is added to a solution of sodium acetate, then hydronium ions react quantitatively with acetate anions ... 

The question asks if this is a buffer solution. A buffer solution contains both a weak acid and its conjugate base as major species. Thus, to answer the question, we must calculate the concentrations of acetate anions and acetic acid in the solution. We use a compressed version of the seven-step method to obtain these concentrations. 

HCl H3 O " and Cl Sodium acetate CH3 CO2 andNa Because the hydronium ion is a strong acid and the acetate anion is a weak base, mixing the solutions results in near-quantitative reaction between these two ions ... 

We need to calculate initial conditions for the stoichiometric point. Recall that the added base has reacted to form acetate anions ... 

Figure 18-10 shows that the pH of an acetic acid solution is attenuated by added acetate anion. As acetate concentration increases, the equilibrium position shifts in the direction of more acetic acid and less H3 O. ... 

Delgado JM, Orts JM, Rodes A. 2005. ATR-SEIRAS study of the adsorption of acetate anions at chemically deposited silver thin film electrodes. Langmuir 21 8809-8816. 

Catalytically active species derived from 4. Spectrophotometric titration of the backbone ligand of the sngar discriminating dinuclear copper(ll) complex N, N-bis[(2-pyridylmethyl)-l,3-diaminopropan-2-olato] (//-acetato) dicoppeftll) perchlorate (Cu2(bpdpo), 4) in the presence of two equivalents of copper(ll) ions with sodium hydroxide indicates successive replacement of the bridging acetate anion bound in the sohd state with two hydroxyl ions and two water molecnles in alkaline aqneons solntion (eqs. 2 and 3) (20-22). Two species, [Cu2(L h)(OH)] (4a) and [Cn2(L h)(OH)2] (4b), are thus observed in a pH-dependent equihbrium (20). 

What we might expect as a pathway for this reaction would be simple Sn2 displacement (p. 98) of the good leaving group— brosylate anion—by acetate anion ... 

Figure 3.9 Calculated electrostatic potential maps for acetate anion and ethoxide anion. Although both molecules carry the same -1 net charge, acetate stabilizes the charge better by dispersing it over both oxygens.

The negative charge in acetate anion is evenly distributed over the two oxygens. 

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