229639-93-4Relevant academic research and scientific papers
Diastereo- and enantioselective synthesis of δ2-1,2,4-oxadiazolines by 1,3-dipolar cycloaddition of nitrile oxides with chiral hydrazones
Enders, Dieter,Meyer, Ilka,Runsink, Jan,Raabe, Gerhard
, p. 995 - 1024 (2007/10/03)
Diastereo- and enantioselective 1,3-dipolar cycloadditions of nitrile oxides (3) with α,β-unsaturated hydrazones (2) gave spiro oxadiazolines (4) in good yields and low to excellent diastereomeric excesses (de = 5 - ≥98%). Open chain hydrazones (6) afforded 5,5-disubstituted Δ2-1,2,4-oxadiazolines (7). A subsequent N-N bond cleavage to remove the chiral auxiliary was achieved with formic acid and gave the oxadiazolines (8) (ee = 0 - 91%).
