15597.eh12.220-24611/0a/052:19Page229 EQA Solutions o Problems229 dCH,cH0 H CH o. 0 (mainly),via g(OCCH) All products are formed as racemic mixtures (+enantiomer) g 风 Note the anti-Markovnikov regiochemistry for hydroboration. 37.A brief analysis of possible choices is provided for each problem oH月 (a)Need Markovnikov hydration of (CH)CHCH-CH or anti-Markovnikov hydration o H OH (CH3)2C=CHCH3.Either can be done. GG-0 CHC-CCCUCCHOC CHCHCH,CICH,CHCHOCHCH)Solutions to Problems • 229 (c) (d) (e) All products are formed as racemic mixtures. (f ) (g) Note the anti-Markovnikov regiochemistry for hydroboration. 37. A brief analysis of possible choices is provided for each problem. OH H g g (a) Need Markovnikov hydration of (CH3)2CHCHPCH2, or anti-Markovnikov hydration of (b) Need addition to propene of “Cl
” and “(CH3)2CHO.” Cl2 is the source of “Cl
”, and (CH3)2CHOH provides the nucleophile. Cl2, (CH3)2CHOH solvent CH2 CHCH3 ClCH2CH(CH3)OCH(CH3)2 1. Hg(OAc)2, H2O 2. NaBH4, NaOH, H2O (CH3)2C (CH3)2CHCH (CH3)2CHCHOHCH3 H OH CHCH3. Either can be done. CH2 1. BH3, THF 2. NaOH, H2O2, H2O (CH3)2C CHCH3 (CH3)2CHCHOHCH3 H HO CH3 Blocks top syn addition to bottom CH3 N3 CH3 Br (
enantiomer) H H CH3
OCH3 (mainly), via CH3 CH3 O Blocks top, so Hg attacks bottom
Hg(OCCH3) OCH3 CH3CH2 O H CH3CH2 OH Trans, from anti addition Br H 1559T_ch12_220-246 11/04/05 2:19 Page 229