Journal
JOURNAL OF ORGANIC CHEMISTRY
Volume 79, Issue 21, Pages 10456-10465Publisher
AMER CHEMICAL SOC
DOI: 10.1021/jo502095k
Keywords
-
Categories
Funding
- Fundacao para a Ciencia e a Tecnologia (FCT)
- Portuguese Agency for Scientific Research (Coimbra Chemistry Centre) [Pest-OE/QUI/UI0313/2014]
- Portuguese Agency for Scientific Research (Centro de Quimica Estrutural) [Pest-OE/QUI/UI0100/2013, RECI/QEQ-QIN70189/2012]
- FCT [SFRH/BPD/71683/2010, SFRH/BPD/84413/2012, SFRH/BPD/64423/2009]
- National Funds through FCT (Portuguese Foundation for Science and Technology) [REEQ/481/QUI/2006, RECI/QEQQFI/0168/2012, CENTRO-07-CT62-FEDER-002012]
Ask authors/readers for more resources
The reactivity of nitrosoalkenes toward dipyrromethanes, pyrrole, and 2,5-dimethylpyrrole is described. 1-(p-Bromophenyl)nitrosoethylene shows a different chemical behavior with these heterocycles than the previously reported reactions of ethyl nitrosoacrylate, which proceeds via a Diels-Alder reaction. 1-(p-Bromophenyl)nitrosoethylene reacts with dipyrromethanes and pyrrole to afford two isomeric oximes via conjugate addition followed by rearomatization of the pyrrole unit. On the other hand, this nitrosoalkene reacts with 2,5-dimethylpyrrole through an initial conjugate addition followed by intramolecular O- and N-nucleophilic addition with the formation of the corresponding bicyclic oxazine and five-membered cyclic nitrone, respectively. Quantum chemical calculations, at the DFT level of theory, indicate that the barriers associated with the Diels-Alder reactions of ethyl nitrosoacrylate are over 30 kJ/mol lower than those that would be required for the cycloadditions of 1-(p-bromophenyl)nitrosoethylene. Thus, calculations predict that the Diels-Alder reaction is privileged in the case of ethyl nitrosoacrylate and point to a different reaction pathway for 1-(p-bromophenyl)nitrosoethylene, corroborating the experimental findings.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available