Premium
Unexpected Migratory Insertion Reactions of M(alkyl) 2 (M=Zn, Cd) and Diamidocarbenes
Author(s) -
Collins Lee R.,
Hierlmeier Gabriele,
Mahon Mary F.,
Riddlestone Ian M.,
Whittlesey Michael K.
Publication year - 2015
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201406406
Subject(s) - electrophile , migratory insertion , alkyl , reactivity (psychology) , nucleophile , chemistry , metal , catalysis , medicinal chemistry , inert , insertion reaction , stereochemistry , organic chemistry , medicine , alternative medicine , pathology
The electrophilic character of free diamidocarbenes (DACs) allows them to activate inert bonds in small molecules, such as NH 3 and P 4 . Herein, we report that metal coordinated DACs also exhibit electrophilic reactivity, undergoing attack by Zn and Cd dialkyl precursors to afford the migratory insertion products [(6‐MesDAC‐R)MR] (M=Zn, Cd; R=Et, Me; Mes=mesityl). These species were formed via the spectroscopically characterised intermediates [(6‐MesDAC)MR 2 ], exhibiting barriers to migratory insertion which increase in the order MR 2 = ZnEt 2 < ZnMe 2 < CdMe 2 . Compound [(6‐MesDAC‐Me)CdMe] showed limited stability, undergoing deposition of Cd metal, by an apparent β‐H elimination pathway. These results raise doubts about the suitability of diamidocarbenes as ligands in catalytic reactions involving metal species bearing nucleophilic ligands (M‐R, M‐H).