1559T_ch17-304-32211/3/0510:48Page318 EQA 318.Chapter 17 ALDEHYDES AND KETONES:THE CARBONYL GROUF 9 (c)(CH)CHOCCH,CH(CH)(CH)CHCOCH CH(CH HOCHCH-OH PCC.CH.Ck OH C.C CH:OH (b)Careful!R H HOCH.CHOH,H Now go to work on the rest. O O B B (c) (CH3)2CHOCCH2CH(CH3)2 (CH3)2CHCOCH2CH(CH3)2 O O B B (d) (e) C6H5OCCH3 C6H5COCH3 50. (a) Approach: You need a reaction between CH3MgI and a ketone carbonyl group, so the aldehyde will have to be protected. (b) Careful! Better protect the aldehyde again, or it will die when you apply any of several methods to get rid of the alcohol. Here’s one: Now go to work on the rest. H
, H2O H MgBr O O H C O H 2. Mg, (CH3CH2)2O 1. PBr3 HOCH2CH2OH, H
H OH H OH O O C H O H 2. H
, H2O 1. CH3MgI, (CH3CH2)2O CH3 OH O O O H C O H HOCH2CH2OH, H
C O H H OH PCC, CH2Cl2 O O H H OH O O O O 318 • Chapter 17 ALDEHYDES AND KETONES: THE CARBONYL GROUP 1559T_ch17_304-322 11/3/05 10:48 Page 318