59305-33-8Relevant academic research and scientific papers
Stereoselective peterson olefinations from bench-stable reagents and N-phenyl imines
Das, Manas,Manvar, Atul,Jacolot, Ma?wenn,Blangetti, Marco,Jones, Roderick C.,O'Shea, Donal F.
, p. 8737 - 8740 (2015/06/08)
The synthesis of bench-stable α,α-bis(trimethylsilyl)toluenes and tris(trimethylsilyl)methane is described and their use in stereoselective Peterson olefinations has been achieved with a wide substrate scope. Product stereoselectivity was poor with carbonyl electrophiles (E/Z ~1:1 to 4:1) though this was significantly improved by employing the corresponding substituted N-benzylideneaniline (up to 99:1) as an alternative electrophile. The olefination byproduct was identified as N,N-bis(trimethylsilyl)aniline and could be easily separated from product by aqueous acid extraction. Evidence for an autocatalytic cycle has been obtained.
General Ambient Temperature Benzylic Metalations Using Mixed-Metal Li/K-TMP Amide
Manvar, Atul,Fleming, Patricia,O'Shea, Donal F.
, p. 8727 - 8738 (2015/09/15)
Highly regioselective benzylic metalations in hydrocarbon solvent have been achieved at rt and 0 °C using a mixed-metal Li/K-TMP amide comprised of KOtBu, BuLi, and 2,2,6,6,-tetramethylpiperidine (TMP(H)). Mixing of KOtBu, BuLi, and TMP(H) in heptane gave a solution of the base mixture which when used in deuterium labeling experiments confirmed the requirement of the three reagent components for both reactivity and selectivity. The reaction protocol is operationally straightforward and found to be applicable to a broad range of substrates. Upon generation of the metalated products, they are reacted in heptane at ambient temperature in a variety of synthetically useful ways. Illustrated examples include generation of the benzyltrimethylsilanes and α,α-bis(trimethylsilyl)toluenes reagents, which are bench-stable surrogates of benzyl anions and α-silyl carbanions utilized for nucleophilic addition and Peterson olefination reactions. Direct C-C couplings mediated by 1,2-dibromoethane provided entries into bibenzyls and [2.2]metacyclophanes. Comparison of reaction outcomes with the same reactions carried out in THF at -78 °C showed no negative effects for conducting the reactions under these milder more user-friendly conditions.
Synthesis of α-Lithioarylmethanes of m-Xylene and its α-Trimethylsilyl Derivatives; Crystal Structure of 2>
Engelhardt, Lutz M.,Leung, Wing-Por,Raston, Colin L.,White, Allan H.
, p. 337 - 344 (2007/10/02)
Crystalline organolithium complexes > (R=R'=H, R=R'=SiMe3, pmdien=NNN'N"N"-pentamethyldiethylenetriamine), > (tmen=NNN'N'-tetramethylethylenediamine), and 2> have
