Abstract
The diastereoselective ultrasonically induced zinc-copper 1,4-addition
of alkyl iodides to chiral α,β-unsaturated systems 1 -3 in
aqueous media is reported. The reaction of methylenedioxolanone 1 with a variety of alkyl iodides takes
place in good yields and with high diastereomeric excess. The 1,4-addition
to (Z )- and (E )-γ,δ-dioxolanyl-α,β-unsaturated
esters 2 and 3 also
proceeds with good yields: the Z -isomer 2 gives good diastereoselectivities while
the reactions with the E -isomer 3 are non-stereoselective.
Key words
aqueous media - Michael additions - radical
reactions - stereoselective synthesis - zinc-copper
couple
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