36771-30-9Relevant articles and documents
Michael Addition of Soft Carbon Nucleophiles to Alkylidene Isoxazol-5-ones: A Divergent Entry to β-Branched Carbonyl Compounds
Capreti, Naylil M. R.,Jurberg, Igor D.
supporting information, p. 2490 - 2493 (2015/05/27)
A novel, divergent strategy toward the synthesis of β-branched (and linear) carbonyl compounds is developed by taking advantage of alkylidene isoxazol-5-ones as key building blocks. The yields obtained range from good to excellent, therefore making the described methods attractive options for building such molecules. (Chemical Equation).
A new convergent approach to α-branched alkynes
Renard, Delphine,Rezaei, Hadi,Zard, Samir Z.
, p. 1257 - 1260 (2007/10/03)
A variety of α-branched alkynes can be easily assembled by a Knoevenagel type condensation of 4-unsubstituted isoxazolin-5-ones with aldehydes or ketones, followed by conjugate addition of an organometallic reagent and nitrosative cleavage of the heterocy
4-Alkylideneisoxazol-5-ones. Synthesis, Tautomerism, and Rearrangement to Pyrroles
Wollweber, Hans-Joachim,Wentrup, Curt
, p. 2041 - 2047 (2007/10/02)
The synthesis of several 4-alkylidene- and 4-cycloalkylideneisoxazol-5-ones is described and their tautomerism is investigated by 13C NMR, 1H NMR and IR spectroscopy.Through hydrogen shifts involving the exocyclic substituent (2-propylidene, cyclopentylidene, or 2-indanylidene) these compounds can exist in CH, NH, or OH forms (Scheme II).The CH form is favored in solvents of low polarity (CDCl3) and in the absence of special enthalpic and conjugative effects stabilizing the NH form.The NH form is favored in polar solvents (Me2SO), and its dominance is accentuated when the vinylic substituent is stabilized thermodynamically and conjugationally.The OH form is not observed directly, but the ionized O- form is present in the morpholinium salts of 15, 16, and 17.In the 2-propylidene derivative 12 only the CH form was spectroscopically detectable, but H/D exchange experiments on this and other isoxazolones showed that tautomerism does take place (12 * 24).The alkylideneisoxazolones rearrange to pyrrolecarboxylic acids on flash vacuum pyrolysis.Of two possible mechanisms, a vinylnitrene mechanism (Scheme IV) and a nitrile ylide mechanism (Scheme V), the former is shown to apply.The pyrrolecarboxylic acids often decarboxylate under the reaction conditions.