137897-38-2Relevant academic research and scientific papers
New Trialkylsilyl Enol Ether Chemistry: Direct 1,2-Bis-azidonation of Triisopropylsilyl Enol Ethers: an Azido-radical Addition Process Promoted by TEMPO
Magnus, Philip,Roe, Michael B.,Hulme, Christopher
, p. 263 - 266 (1995)
Treatment of triisopropylsilyl enol ethers with PhIO/TMSN3/TEMPO(cat.) -45 deg C results in 1,2-bis-azidonation, which appears to occur through a radical addition process; the 1-azido group can be replaced by carbon nucleophiles such as allyl,
Applications of the β-azidonation reaction to organic synthesis. α,β- Enones, conjugate addition, and γ-lactam annulation
Magnus, Philip
, p. 12486 - 12499 (2007/10/03)
The β-azido functionalization reaction provides a mechanistically different enone synthesis that involves treatment of 2 with fluoride anion to effect desilylation and concomitant β-elimination to give 3. Table 1 lists a number of examples of the direct conversion of a TIPS enol ether into the corresponding α,β-enone via a β-azido TIPS enol ether. The β-azido group can be ionized with Me3Al or Me2AlCl and the intermediate enonium ion trapped by a variety of nucleophiles such as an allylstannane, electron-rich aromatics, TMS enol ethers, Et2AlCN, Me2AlCCR, Me4AlLi, and vinylaluminum reagents to give the products listed in Table 2. The diastereoselectivity of the reaction of a 4-substituted enonium ion with indole shows an unusual increase of selectivity with increasing temperature. Reduction of the azide 2 provides access to β-amino TIPS enol ethers 5, which, for example, can be converted into a cinnamide derivative and cyclized via a putative 'ene' process into a γ-lactam.
Hypervalent iodine chemistry: New oxidation reactions using the iodosylbenzene-trimethylsilyl azide reagent combination. Direct α- and β-azido functionalization of triisopropylsilyl enol ethers
Magnus, Philip,Lacour, Jér?me,Evans, P. Andrew,Roe, Michael B.,Huhne, Christopher
, p. 3406 - 3418 (2007/10/03)
Treatment of triisopropylsilyl (TIPS) enol ethers with PhIO/TMSN3/at -18 to -15°C rapidly (5 min) gave β-azido TIPS enol ethers in high yields, with only traces of the α-azido adduct. The reaction is very sensitive to temperature changes, with
