Magnesium
Name Reactions
Recent Literature
An intermolecular pinacol coupling of aromatic or aliphatic carbonyl
compounds catalyzed by a complex of samarium diiodide (SmI2) with
tetraglyme in the presence of Me2SiCl2 and Mg is
described. Diastereoselectivity of up to 95/5 (±/meso) has been achieved for
aliphatic aldehydes and up to 19/81 (±/meso) for aromatic aldehydes. De
values of up to 99% have been achieved in intramolecular pinacol coupling
reactions.
H. C. Aspinall, N. Greeves, C. Valla, Org. Lett., 2005, 7, 1919-1922.
Rieke Ni generated in situ was able to promote the pinacol coupling of
various carbonyls efficiently. Another catalytically effective, cheaper
and more convenient NiCl2(Cat.)/Mg/TMSCl system was designed
and developed further successfully. Single-electron transfer (SET)
mechanisms for the coupling reactions and the DL/meso
diastereoselectivity were also explained.
L. Shi, C.-A. Fan, Y.-Q. Tu, M. Wang, F.-M. Zhang, Tetrahedron,
2004, 60, 2851-2855.
Magnesium in methanol is an effective reagent for the chemoselective
reduction of ozonides and other peroxides. Mg/MeOH is significantly more
reactive than Me2S or PPh3 and somewhat more
reactive than Zn/HOAc.
P. Dai, P. H. Dussault, T. K. Trullinger, J. Org. Chem., 2004, 69, 2851-2852.
