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Updated: May 29, 2025
A Protocol for Safe Lithiation Reactions Using Organolithium Reagents
Published on: November 12, 2016
The Diverse Reactivity of an Al(I) Carbenoid Towards Phosphorus-Based Ylides. The Crucial Role of Co-Crystallised
Anton Dmitrienko1, Melanie Pilkington1, Georgii I Nikonov1
1Chemistry Department, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario, L2S 3A1, Canada.
Abstract:
Attempts to generate NacNacAl-based (NacNac=[ArNC(Me)CHC(Me)NAr]-; Ar=2,6-iPr2C6H3) alkylidenes via reactions with trimethyl(methylidene), triphenyl(methylidene) and triethyl(ethylidene) phosphiranes led to new and unexpected reactivity patterns. Reaction with Me3P=CH2 resulted in the intermolecular deprotonation of the NacNac -CCH3 backbone. Reaction with Ph3P=CH2*LiI afforded an equimolar mixture of NacNacAlH2 and the ortho-metalated adduct, NacNac'Al(η(C,C)2-CH2=PPh2(o-C6H4)) (NacNac'=[ArNC(Me)CHC(=CH2)NAr]2-). Finally, the use of Et3P=CHMe*LiBr resulted in the fragmentation of the NacNac moiety.
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