title: Azirinium ylides from α-diazoketones and 2H-azirines on the route to 2H-1,4-oxazines: three-membered ring opening vs 1,5-cyclization
metadata.name: dc.contributor.author
metadata.value: Rostovskii, Nikolai V.
metadata.lang: -
metadata.name: dc.contributor.author
metadata.value: Novikov, Mikhail S.
metadata.lang: -
metadata.name: dc.contributor.author
metadata.value: Khlebnikov, Alexander F.
metadata.lang: -
metadata.name: dc.contributor.author
metadata.value: Starova, Galina L.
metadata.lang: -
metadata.name: dc.contributor.author
metadata.value: Avdontseva, Margarita S.
metadata.lang: -
metadata.name: dc.date.accessioned
metadata.value: 2016-04-07T21:31:37Z
metadata.lang: -
metadata.name: dc.date.available
metadata.value: 2016-04-07T21:31:37Z
metadata.lang: -
metadata.name: dc.date.issued
metadata.value: 2015-03
metadata.lang: -
metadata.name: dc.identifier.citation
metadata.value: Beilstein J. Org. Chem. 2015, 11, 302–312
metadata.lang: en_GB
metadata.name: dc.identifier.issn
metadata.value: 1860-5397
metadata.lang: -
metadata.name: dc.identifier.uri
metadata.value: http://hdl.handle.net/11701/1961
metadata.lang: -
metadata.name: dc.description.abstract
metadata.value: Strained azirinium ylides derived from 2H-azirines and α-diazoketones under Rh(II)-catalysis can undergo either irreversible ring opening across the N–C2 bond to 2-azabuta-1,3-dienes that further cyclize to 2H-1,4-oxazines or reversibly undergo a 1,5-cyclization to dihydroazireno[2,1-b]oxazoles. Dihydroazireno[2,1-b]oxazoles derived from 3-aryl-2H-azirines and 3-diazoacetylacetone or ethyl diazoacetoacetate are able to cycloadd to acetyl(methyl)ketene generated from 3-diazoacetylacetone under Rh(II) catalysis to give 4,6-dioxa-1-azabicyclo[3.2.1]oct-2-ene and/or 5,7-dioxa-1-azabicyclo[4.3.1]deca-3,8-diene-2-one derivatives. According to DFT calculations (B3LYP/6-31+G(d,p)), the cycloaddition can involve two modes of nucleophilic attack of the dihydroazireno[2,1-b]oxazole intermediate on acetyl(methyl)ketene followed by aziridine ring opening into atropoisomeric oxazolium betaines and cyclization. Azirinium ylides generated from 2,3-di- and 2,2,3-triaryl-substituted azirines give rise to only 2-azabuta-1,3-dienes and/or 2H-1,4-oxazines.
metadata.lang: en_GB
metadata.name: dc.language.iso
metadata.value: en
metadata.lang: en_GB
metadata.name: dc.publisher
metadata.value: Beilstein-Institut
metadata.lang: en_GB
metadata.name: dc.relation.ispartofseries
metadata.value: Beilstein Journal of Organic Chemistry;Vol. 15
metadata.lang: -
metadata.name: dc.subject
metadata.value: nitrogen ylides
metadata.lang: en_GB
metadata.name: dc.subject
metadata.value: diazoketones
metadata.lang: en_GB
metadata.name: dc.subject
metadata.value: Azirines
metadata.lang: en_GB
metadata.name: dc.subject
metadata.value: 2H-1,4-oxazines
metadata.lang: en_GB
metadata.name: dc.subject
metadata.value: 2-azabuta-1,3-dienes
metadata.lang: en_GB
metadata.name: dc.title
metadata.value: Azirinium ylides from α-diazoketones and 2H-azirines on the route to 2H-1,4-oxazines: three-membered ring opening vs 1,5-cyclization
metadata.lang: en_GB
metadata.name: dc.type
metadata.value: Article
metadata.lang: en_GB
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resources.url: https://dspace.spbu.ru/bitstream/11701/1961/1/grafical%20abstract2.png
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