87378-68-5Relevant academic research and scientific papers
Reaction of 4-Methylene-5(4H)-oxazolones With Diazomethane
Arenal, I.,Bernabe, M.,Alvarez, E. Fernandez,Izquierdo, M. L.,Penades, S.
, p. 607 - 614 (2007/10/02)
The reaction of diazomethane with some (E) and (Z)-2-substituted-4-methylene-5(4)-oxazolones (1a-c) under two different conditions, has been studied. (E) and (Z)-1,2-disubstituted-7-oxo-6-oxa-4-azaspiro-hept-4-enes (3a-c, 4a-c) were mainly obtained, together with multiple addition compounds.The reaction showed to be stereoselective only when the substituents were aromatic.Acid hydrolysis of compounds 3a and 4a produced a mixture of (E) and (Z)-3,5-disubstituted-tetrahydrofuran-2-ones (8a, 9a).Smooth methanolysis of the ring led to (E) and (Z)-1-benzamido-cyclopropanecarboxylic esters (10a-c, 11a-c), which, on acid hydrolysis, gave (E) and (Z)-1-amino-2-phenylcyclopropanecarboxylic acids 12a and 13a.The pmr spectra have been analyzed by an iterative computer method, and the computed best values obtained have been used to deduce the stereochemistry of the spiroderivatives.
