160149-06-4Relevant articles and documents
Generation and Cycloadditions of 4,5-Dihydrooxazole- and Oxazolidine-4-carbonitrile N-Oxides
Blake, Alexander J.,Boyd, Ewan C.,Gould, Robert O.,Paton, R. Michael
, p. 2841 - 2848 (2007/10/02)
A route to 2-phenyl-4,5-dihydrooxazole-4-carbonitrile N-oxide 7 has been developed starting from (S)-serine methyl ester and involving dehydration of the 4-nitromethyl derivative 13 using m-tolylene diisocyanate and triethylamine.Cycloaddition of the nitrile oxide to styrene afforded a 55:45 mixture of diastereoisomeric dihydroisoxazoles 21 and 22; furazan N-oxides 19 and 20 were also formed in a competing dimerisation.The analogous (R)-oxazolidine-4-carbonitrile oxide 8, also prepared from (S)-serine methyl ester, reacted similarly with styrene, oct-1-ene and diethyl fumarate to afford ca. 1:1 mixtures of adducts.The structures of the dihydrooxazole-dihydroisoxazole adduct 21 and furazan N-oxide 20 were determined by X-ray crystallography.