Question

5. While the carbonyl stretching frequency for simple aldeydes. Ketones is about 1710 cm, the carbony stretching frequency for esters is about A) 1660 cm B) 1700 cm C) 1735 cm D) 1800 cm E) 2200 cm-1 6. The 'H NMR spectrum of an unknown acid has the following peaks: (ppm) = 12.71 (1H, s). 8.04 (2H, d), 7.30 (2H, d), 2.41 (3H, s) c) ОН 7. What type of product results when 3-pentanone reacts with dimethylamine? A) enolate B) enol C ) amide D) imine (E) enamine 8. The a-halogenation of cyclohexanone (A) is catalyzed by base B) is slowed by the presence of acid c) requires one equivalent of base D) requires one equivalent of acid E) is catalyzed by the sodium halide salt

Answer 1

5. Carbonge stretching forequency of estars occur at 173sum' • 6. y he beans given are ; 2.41131, d), 7.30(2H,d), 810412H,d), 12.111 11,3) If we add all the protons, total no of protons = 3+2+2+1=8 .. Thus, the options les and (d) are odso probable . Now since the aromatic protons show symmetric to signals in a protons and 7.30 and a protons at 8.04, it means that compound is symmetrically substituted. Hence, option (as is ruled out. if we Finally, focuss on the most proton, down field it characteristic is of the carbonylic acid . proton . Aldehyde proton resonates at dua-10 bpm. Hence; option (d in the right answer. The structure vinote id : . 12.7113) HK . HBC 8.04(d, deshielded • He due to rOq H group) - 7.30 ld, shielded 2:41 (3) due to ettz group) 7. enamine is the answer. 8. &- halogenation of cyclohexanone is catalyzed by base. bare stable carb union . X: halogen