6533b839fe1ef96bd12a663e

RESEARCH PRODUCT

Dihydrooxazine Oxides as Key Intermediates in Organocatalytic Michael Additions of Aldehydes to Nitroalkenes

Gokarneswar SahooPetri M. PihkoMikko MelartoHasibur RahamanImre PápaiArto ValkonenÁDám Madarász

subject

chemistry.chemical_classificationchemistryOrganic chemistryProtonationGeneral ChemistryNuclear magnetic resonance spectroscopyGeneral Medicineta116CatalysisAlkyl

description

Pause and play: dihydrooxazine oxides are stable intermediates that are protonated directly, without the intermediacy of the zwitterions, in organocatalytic Michael additions of aldehydes and nitroalkenes (see scheme, R=alkyl). Protonation of these species explains both the role of the acid co-catalyst in these reactions, and the observed stereochemistry when the reaction is conducted with α-alkylnitroalkenes.

https://doi.org/10.1002/ange.201204833