Question

Please give a detailed but short analysis as to why Acetophenone under went these reactions with these conditions.

Chemical Data: a. Reaction of the unknown with 2,4- dinitrophenylhydrazine: an orange hydrazone precipitate was observed. b. Reaction of the unknown with Tollens' reagent: no silver mirror was observed. c. Reaction of the unknown with Permanganate: no color change was observed. d. Reaction of the unknown with Chromic Acid reagent: no green precipitate was observed. e. Reaction of the unknown with Fehling's reagent: no color change was observed. f. Reaction of the unknown with Schiff's reagent: no color change was observed. g. Reaction of the unknown in the lodoform reaction: a yellow precipitate was observed.

Answer 1

Auswer Str. of acetophenon CH 3 P CH3 Acetophenon contains Kelone o functional which is a aromatic Ketone. group. Ketone and aldehyde giver 2,4 - DNP Test. Since acelophenone is a aromatic ketone it gives positive 2,4 - DNP test. so Phy NOL ET NO2 Xo+HN-HN Etoh Pha "=N-NH Y NO2 et orange hydrazone NO2 PPT (6 Tollen's reagent only give positive test for alder function group. Since acetophenon does not Contain any aldehyde functional group so negative test of side chain unsaturation is present then only give the cat colour charge of alkaline permanganate Som pink to colourless. As acetophenon does not Contain unsat side chain Unsaturation (e=e) so negative test. a Chrowic acid test is positive for 10 20 alcohol and aldehyde where these are bonusted to oxidized to and Chrowie acid (er 6+) itself reduced to e3+ which change the color. Since acetophenon is a ketone (aromatic) so it gives negative test. e since Phyo does not contains any aldehyde CH3 group so no color change with Fehling's reaght, Page 1 See Next page

Schiff reagent is a winderd nucleophile, it does not react with aromatic ketone. As acetophenon is an aromatic Ketone so does not ive any positive test on no color change with Schiff reaget. In presence of Nad Aant and excess I2 the methyl Ketones are converted to its acid (sodium salt) and yellow ppt of CHL Haq) e Excessing put onă + Ett CHIZ L Naolt yellow pptr As acetophenon is a positive iodo form page 2 methyl Kelone test. so it gives