Pyridinium chlorochromate, 304,

PCC IS pyridinium chlorochromate PDC is pyridinium dichromate Both are used in dichloromethane ... 

Different reagents react with different bonds in the same molecule. PCC represents pyridinium chlorochromate. 

Pyridinium chloride, N-(4-pyridyl)-hydrochloride quaternization, 2, 175 reactions with amines, 2, 241 Pyridinium chlorochromates as oxidizing agents, 2, 170 reactions, 2, 34 Pyridinium dichromate as oxidizing agent, 2, 170 Pyridinium l-dicyanomethylide... 

Et3NH ClCi03, CICH2CH2CI, 2 h, it, 60-90% yield. This reagent was reported to work better than PCC (pyridinium chlorochromate). 

Oxidation of tim5-4-(2,2,2-tnfluoro-l-hydroxy 1 tnfluoromethylethyl)cyclo-hexanol with pyridinium chlorochromate results m the correspondmg cyclic ketone whereas oxidation with nitnc acid m the presence of a catalyst causes ring cleavage [50] (equation 46)... 

Conditions that do pennit the easy isolation of aldehydes in good yield by oxidation of primaiy alcohols employ vaiious Cr(VI) species as the oxidant in anhydrous media. Two such reagents ar e pyridinium chlorochromate (PCC), C5H5NH ClCi03, and pyridinium dichromate (PDC), (C5H5NH)2 Ci207 both are used in dichloromethane. 

This group is stable to 3 AHCl, 100° 3 ANaOH, 100° H2, 1200 psi O3, MeOH, —78° RaNi, 100° LiAlH4 Jones reagent and pyridinium chlorochromate (PCC). It has also been used for protection of the anomeric hydroxyl during oligosaccharide synthesis. ... 

Pyridinium chlorochromate. In this case, the alcohol that is cleaved is simultaneously oxidized to give a ketone. ... 

Secondary alcohols are oxidized easily and in high yield to give ketones. For large-scale oxidations, an inexpensive reagent such as Na2Cr207 aqueous acetic acid might be used. For a more sensitive or costly alcohol, however, pyridinium chlorochromate is often used because the reaction is milder and occurs at lower temperatures. 

Perhaps the most important reaction of alcohols is their oxidation to carbonyl compounds. Primary alcohols yield either aldehydes or carboxylic acids, secondary alcohols yield ketones, but tertiary alcohols are not normally oxidized. Pyridinium chlorochromate (PCC) in dichloromethane is often used for oxidizing primary alcohols to aldehydes and secondary alcohols to ketones. A solution of Cr03 in aqueous acid is frequently used for oxidizing primary alcohols to carboxylic acids and secondary alcohols to ketones. 

Draw the structure of the carbonyl compound(s) from which each of th< following alcohols might have been prepared, and show the products yen. would obtain by treatment of each alcohol with (i) Na metal, (ii) SOCl2, anc (iii) pyridinium chlorochromate. 

Q Primary alcohols can be oxidized to give aldehydes (Section 17.7). The reaction is often carried out using pyridinium chlorochromate (PCC) in dichloro-methane solvent at room temperature. 

What product would you obtain by reduction of digitoxigenin (Problem 27.39) with LiAl.H4 By oxidation with pyridinium chlorochromate ... 

Pauling, Linus Carl, 12 PCC, see Pyridinium chlorochromate PCR, see Polymerase chain reaction, 1117-1118... 

The C2-symmetric epoxide 23 (Scheme 7) reacts smoothly with carbon nucleophiles. For example, treatment of 23 with lithium dimethylcuprate proceeds with inversion of configuration, resulting in the formation of alcohol 28. An important consequence of the C2 symmetry of 23 is that the attack of the organometallic reagent upon either one of the two epoxide carbons produces the same product. After simultaneous hydrogenolysis of the two benzyl ethers in 28, protection of the 1,2-diol as an acetonide ring can be easily achieved by the use of 2,2-dimethoxypropane and camphor-sulfonic acid (CSA). It is necessary to briefly expose the crude product from the latter reaction to methanol and CSA so that the mixed acyclic ketal can be cleaved (see 29—>30). Oxidation of alcohol 30 with pyridinium chlorochromate (PCC) provides alde-... 

This protecting group is stable to n-BuLi (THF, — 25°C), s-BuLi (Et20, -25 °C), LDA, saturated ammonium chloride solution, water, MeOH, sodium hydrogen carbonate solution (2m), pyridinium dichromate/ dichloromethane, and, surprisingly, KF.2H20/THF/H20. It is unstable to 0.1 M HC1, 1m KOH, 75% aqueous AcOH, NaBH4, and pyridinium chlorochromate/dichloromethane. 

N-Methyl-2-pyrrolidinone 2 KHSO5 KHSO4 K2SO4 Polymeric backbone Pyridinium chlorochromate Pyridinium dichromate Polyethylene glycol... 

Pyridinium chlorochromate Pyridinium dichromate Polyethylene glycol... 

One such example is pyridinium chlorochromate, or PCC for short, which is prepared in the following way ... 

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