Regioisomeric and substituent effects upon the outcome of the reaction of 1-borodienes with nitrosoarene compounds
Eberlin, Ludovic; Carboni, Bertrand; Whiting, Andrew
Professor Andrew Whiting email@example.com
A study of the reactivity of 1-borodienes with nitrosoarene compounds has been carried out showing an outcome that differs according to the hybridization state of the boron moiety. Using an sp2 boron substituent, a one-pot hetero-Diels–Alder/ring contraction cascade occurred to afford N-arylpyrroles with low to good yields depending on the electronic properties of the substituents on the borodiene, whereas an sp3 boron substituent led to the formation of stable boro-oxazines with high regioselectivity in most of the cases, in moderate to good yields. 1H and 11B NMR studies on two boro-oxazine regioisomers showed that selective deprotection can be performed. Formation of either the pyrrole or the furan derivative is pH- and regioisomer-structure-dependent. The results obtained, together with previous B3LYP calculations, support mechanistic proposals which suggest that pyrrole, or furan, formation proceeds via oxazine formation, followed by a boryl rearrangement and an intramolecular addition–elimination sequence.
Eberlin, L., Carboni, B., & Whiting, A. (2015). Regioisomeric and substituent effects upon the outcome of the reaction of 1-borodienes with nitrosoarene compounds. Journal of Organic Chemistry, 80(13), 6574-6583. https://doi.org/10.1021/acs.joc.5b00593
|Journal Article Type||Article|
|Acceptance Date||Jun 3, 2015|
|Online Publication Date||Jun 3, 2015|
|Publication Date||Jul 2, 2015|
|Deposit Date||Jun 12, 2015|
|Publicly Available Date||Jun 3, 2016|
|Journal||Journal of Organic Chemistry|
|Publisher||American Chemical Society|
|Peer Reviewed||Peer Reviewed|
Accepted Journal Article
This document is the Accepted Manuscript version of a Published Work that appeared in final form in The Journal of Organic Chemistry, copyright © 2015 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/acs.joc.5b00593.