Module I Oxidation Reactions - NPTel
Module I Oxidation Reactions - NPTel
Module I Oxidation Reactions - NPTel
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
NPTEL – Chemistry – Reagents and Organic reactions<br />
AcO<br />
O<br />
Na 2Cr 2O 4<br />
Ac2O, AcOH<br />
AcO<br />
Na 2Cr 2O 4<br />
Ac 2O, AcOH O<br />
Scheme 8<br />
CrO3 in acetic anhydride or acetic acid has been found to transform alkenes to<br />
epoxides (Scheme 9).<br />
Ph<br />
Ph<br />
CrO 3<br />
Ac 2O<br />
Scheme 9<br />
Joint initiative of IITs and IISc – Funded by MHRD Page 32 of 122<br />
Ph<br />
O<br />
Ph<br />
85%<br />
Alkenes can be oxidized by chromyl chloride at low temperature to afford<br />
carbonyl compounds (Scheme 10).<br />
CrO 2Cl 2<br />
CH 2Cl 2<br />
0-5 o C<br />
H<br />
H Zn/H2O CHO<br />
O O<br />
Cr<br />
Cl<br />
Cl<br />
Scheme 10<br />
1.3.8 <strong>Oxidation</strong> of Aromatic Side Chains<br />
The selective oxidation of alkyl chains attached to an aromatic ring can be<br />
carried out with CrO3 in acetic anhydride. Thus, p-nitrotoluene is converted into p-<br />
nitrobenzylidine diacetate, which on hydrolysis in the presence of acid gives p-<br />
nitrobenzaldehyde (Scheme 11).<br />
O<br />
O<br />
75%
Change language