Page 211 - Arrow Pushing in Inorganic Chemistry A Logical Approach to the Chemistry of the Main Group Elements
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5B.14 THE VILSMEIER–HAACK REACTION 191
The structure of FePc is as follows:
N
N N
N Fe N
N N
N
and the best ArNHNHCO Et derivative is the following:
2
O
H
Cl N
N OEt
H
Cl
The mechanism of the FePc-mediated oxidation step is outside the scope of this book. It’s
a fascinating one, however, and may be similar to the famous rebound mechanism of the
iron-containing enzyme cytochrome P450; feel free to look it up in a book on bioinorganic
chemistry or on the Internet.
REVIEW PROBLEM 5B.21 *
Would you describe the Mitsunobu reaction as mechanistically similar to the Appel
reaction? Explain.
5B.14* THE VILSMEIER–HAACK REACTION
As our final example of the use of phosphorus in organic synthesis, we will choose the
Vilsmeier–Haack reaction, the classic method for electrophilic formylation (addition of
an aldehyde functionality) of aromatic rings with POCl and dimethylformamide (DMF,
3
HCONMe ).
2
1. DMF, POCI 3 , Δ
ArH ArCHO (5B.79)
2. NaOAc, H O
2
