Highly functionalized organometallics are efficiently prepared in larger quantities (up to 4 g) by directed ortho-metalation using the previously reported amide bases TMP2Mn˙2MgCl2˙4LiCl (TMP = 2,2,6,6-tetramethylpiperidyl), TMP2Fe˙2MgCl2˙4LiCl and TMP3La˙3MgCl2˙5LiCl. The resulting organometallics undergo various reactions with electrophiles like acid chlorides, alkyl iodides, or aldehydes and provide
Atom-Economical Preparation of Aryl- and Heteroaryl-Lanthanum Reagents by Directed<i>ortho</i>-Metalation by Using tmp<sub>3</sub>[La]
作者:Stefan H. Wunderlich、Paul Knochel
DOI:10.1002/chem.200903157
日期:2010.3.15
Chemoselectivity and reactivity: The directedortho‐lanthanation by using tmp3La⋅3MgCl2⋅5LiCl provides triaryl–or heteroaryl–LaIII species in high yields (tmp=2,2,6,6‐tetramethylpiperidyl). A range of functionalities and sensitive heterocycles are tolerated in this metalation procedure. The resulting organometallic species can directly undergo Pd‐catalyzed cross‐coupling reactions (see scheme).