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  lOMoAR cPSD| 22014077   lOMoAR cPSD| 22014077 Chemistry  234 
Synthetic Transformations of  Carbonyl  Compounds –   Problem  Set      Reduction 
Reactions    1) Predict  the  product  for  each   reaction  shown below.   O  NaBH 4    O  1. LiAlH4  CH 3 OH  3 +  2. H O  NH 2  1 . LiAlH  O  . H 2   3 O    H   NaBH4   4    O  CH3OH  +  O  1. L  iAlH  O  1 . LiAlH 4  OH  . H 2   3 O +  2 . H O +  4    Cl  3  O  NaBH  OH  CH 3 OH    O  1. LiAlH4  4    O  +  O 2. H3O  1. L  iAlH 4  O  O  2 . H 3 O +  1. DIBAL-H   -78 ¡C  O    1 . LiAlH  Cl  2. H 4  2O  NH  2 . H 3 O +     1. DIBAL-H    O   -78 ¡C    O  2. 2  H O      2) Predict  the  product  for  each reduction  reaction  below. Pay  close   attention  to  chemoselectivity.          O  O  NaBH4    OCH3   CH3OH      lOMoAR cPSD| 22014077   O  1. DIBAL-H    OH   -78 ¡C  Cl2. H2O  O  O  NaBH4  N  CH3OH  O                  Oxidation  Reactions    3) Predict  the  product  for  each reaction  below. Assume  an  excess of  oxidizing  agent is  present.        O OH   PCCPCC  HO  O   OH   Na2Cr2O7Na2Cr2O7  H  HO    HO2SO4H  H2SO4    OH  Na2Cr2O7Na2Cr2O7    H2SO4  OH  H2SO4        Addition  of  Organometallic  Reagents 
(Grignard, Lithiates,  and  Acetylide  ions)  4) Predict  the  product  for  each reaction  shown below. Assume  an  excess of  organometallic  reagent.        O  1. H 3 CMgBr  2 . H 3 O +        lOMoAR cPSD| 22014077 O  1. Ph MgBr    2 . H O +  H  3  Cl 3C Li 1. H  2. H3O+  O  O  1. H3C MgBr    O  2. H3O+  1.    Ph  Na  O      2. H3O+      OH 1.  H3C Li  O  2. H3O+  1.  MgBr  O OCH3  2. H3O+  1. Mg    Br  2.  O    3. H3O+       Addition  of  Organometallic  Reagents
 (Organocuprates) 5) Predict  the  product  for  each reaction  shown below.   1 . Ph 2 CuLi  2 . H 2 O  O  1 . Ph 2 CuLi  2 . H O      lOMoAR cPSD| 22014077   O  2  1 . (CH 3 ) 2 CuLi  H  2 . H 2 O  O  O  1 . (CH 3 ) 2 CuLi  2 . H 2 O  Cl  O  1 . (CH 3 ) 2 CuLi    O  2. H2O        6) What  reagent  is  needed  to  convert  propanoyl  chloride  to   each of  the  following?        HPh    Ph O  O  OH     OH                7) Draw  the  electron  pushing  mechanism for  the  addition  of   methyl cuprate  to  3-buten-2-one.      O  1. Me2CuLi  2. H O 2                                                           lOMoAR cPSD| 22014077            
Protecting Groups  in  Organic  Synthesis    8) Propose how you  could carry out  the  following  synthetic  sequence.   Hint: PBr3 converts  alcohols  to  bromides.    O?  Br  OHOH                                      9) A student  tried to  carry out  the  reaction  sequence  below, but   none of  the  diol (A)  was formed.  Explain  what went wrong   with the  plan and  design a   successful  synthesis  of  A.    1.  O  OH  Mg  2 . H 3 O +  OH    OH  BrBrMgOH    A                                            General  Mechanisms  10)  Draw the  electron  pushing  mechanism for  each reaction  shown  below.   O  1. H 3 CMgBr  OH  O  2 . H 3 O +  OH            lOMoAR cPSD| 22014077                               OH  O  1. H 3 CMgBr  O  ( excess )  + CH3OH + (CH3)3COH  2 . H 3 O +    OH O  O                                             MgBr  O  O  BrMg  + 2 CH3OH  followed by dilute H +  O  O                                          Synthesis    11) Consider the  following  reaction  sequence.  Identify  the  missing  reagents.        lOMoAR cPSD| 22014077   OHO  1. CH3MgBr+  OH  2. H3O  OH  1. PhMgBr    Ph  O  2. H3O      lOMoAR cPSD| 22014077 Ph      12) Provide a  reasonable synthetic  route to  carry out  the  synthetic   transformation  shown below.     O  ?  O  Ph      H  Ph                            13) Design  a  reasonable synthesis  for  each of  the  following  using   the  provided  starting  materials.    Unless  otherwise  specified,  you  may use  any  other organic  or   inorganic  reagents  as  necessary.    HO    O ?  Ph    OCH3    OH  OH  ?  Br  Ph  Ph  (these are your only  allowed sources of carbon)      lOMoAR cPSD| 22014077   O  O  CH3      Br   ?    H  BrH3C  (these are your only allowed  sources of    carbon)                                            14) Challenge  Question:  Show how 2-hexanone could be  synthesized using   only ethanol  and  any  other inorganic  reagents.  Hint: you  might   need to  use  a  couple of  reactions  from organic  1.          
