Synthesis · 2005 · 32 citations · 0 references
Natural SciencesChemistryGreen ChemistryOrganic ChemistryOrganometallic ChemistryCarboxylic DerivativesHalogen ChemistryHeterocycle SynthesisHeterocyclic ChemistryOrganic SynthesisOrganometallic SynthesisAlkenyl Halide CouplingAllylic FunctionalizationAryl Halide CouplingCarboxylic Acid Derivative SynthesisHalide SynthesisRearrangement ReactionsRing-forming ReactionsStereoselective Synthesis Of Carboxylic Derivatives
The preparation of functionalized 2-substituted allyl bromides and chlorides from carboxylic esters is reported. The carboxylic esters were transformed first to 1-substituted cyclopropanols by treating with ethylmagnesium bromide in the presence of titanium alkoxide. Mesylation of the cyclopropanols followed by halide displacement of the sulfonate group to halogen, accompanied by cyclopropyl-allyl rearrangement, affords the required allyl bromides and chlorides.