Abstract
The reaction of α-chloronitrosocyclohexane with allylzinc reagents in THF selectively
provides O -allylcyclohexanone oximes in very good yields in an ene type reaction followed by
zinc halide elimination. N -Allyl hydroxylamines are formed as minor products via N -allyl nitrones when a nonpolar solvent, e.g. toluene, is employed. In both cases
complete allylic transposition with respect to the allylic organozinc reagent is observed.
Compared to non-metalated allyl compounds, which give N -allyl nitrones upon reaction with α-chloronitroso compounds, the use of zinc as hydrogen
equivalent in an ene type reaction displays a drastic change of reactivity.
Key words
ene reactions - regioselectivity - zinc - allylations - organometallic reagents
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