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A Protocol for Safe Lithiation Reactions Using Organolithium Reagents
Published on: November 12, 2016
[Li(CH(Me)P(Ph)2(NCO2Me))2(THF)2]: crystal, solution, and calculated structure of a N-delocalized lithium phosphazene
Ignacio Fernandez1, Julia Maria Alvarez Gutierrez, Nikolaus Kocher
1Area de Química Orgánica, Universidad de Almería, Carretera de Sacramento s/n, 04120, Almería, Spain.
Abstract:
The first crystal structure of the lithium complex of a P-alkyl-P,P-diphenyl(N-methoxycarbonyl)phosphazene has been characterized. It is dimeric, with the anion chelating the lithium in an unusual six-membered ring. A monomer-dimer equilibrium has been identified in THF solution. Ab initio calculations indicated that the six-membered ring is electronically favored over an alternative Li-C-P-N four-membered ring.
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