Fragmentation of nitrone triflates to 9-membered rings.
A new fragmentative rearrangement of nitrone derivatives to form 9-membered rings is reported. The fragmentations are triggered when nitrones are treated with triflic anhydride; a C-C bond antiperiplanar to the cleaving N-O bond is activated either by an oxygen lone pair or by an electron-rich aromatic ring. In the former case, further cyclization of the 9-membered intermediate leads to a rearranged condensed ring system, but when triggered by arenes, 9-membered ring amides are isolated.
Murphy
John A
JA
WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, United Kingdom. john.murphy@strath.ac.uk
Mahesh
Mohan
M
McPheators
Gary
G
Anand
R Vijaya
RV
McGuire
Thomas M
TM
Carling
Robert
R
Kennedy
Alan R
AR
D000577:Amides / Q000138:chemical synthesis; D003500:Cyclization; D005663:Furans / Q000737:chemistry; D047028:Macrocyclic Compounds / Q000138:chemical synthesis*; D009589:Nitrogen Oxides / Q000737:chemistry*; D013449:Sulfonamides / Q000737:chemistry
D000577:Amides; D005663:Furans; D047028:Macrocyclic Compounds; D009589:Nitrogen Oxides; D013449:Sulfonamides; C015388:nitrones; C474725:triflic anhydride