These are preliminary reports that have not been peer-reviewed. They should not be regarded as conclusive, guide clinical practice/health-related behavior, or be reported in news media as established information. For more information, please see our FAQs.
Preprints are manuscripts made publicly available before they have been submitted for formal peer review and publication. They might contain new research findings or data. Preprints can be a draft or final version of an author's research but must not have been accepted for publication at the time of submission.
submitted on 05.12.2018, 19:32 and posted on 06.12.2018, 14:07by Caroline Apel, Sven Sören Hartmann, Dieter Lentz, Mathias Christmann
Sigmatropic rearrangements constitute an important group
of pericyclic reactions. In contrast to cycloaddition reactions,
examples of catalytic variants of electrocyclic reactions and sigmatropic
rearrangements are still scarce in the chemical literature. Herein,
we report the first organocatalytic Cope rearrangement of in situgenerated
divinylcyclopropanes. The reactive motif is generated by
condensation of 4-(2-vinylcyclopropyl)but-2-enal derivatives and a
secondary amine catalyst to form a transient dienamine. The
cycloheptadiene products can be obtained in high yield and excellent
diastereoselectivity. Importantly, the reaction was demonstrated to be
stereospecific, proceeds under mild conditions, and shows broad
functional group tolerance.