
TY  - JOUR
A1  - Clark-Lewis, JW 
A1  - Taylor, MR 
A1  - Westphalen, J 
T1  - Heterocyclic Compounds from Alloxan and Amines. XIV. Structure of Even-Electron Products Derived from Free-Radical Betaines
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1979
VL  - 32
IS  - 9
SP  - 1943
EP  - 1947
KW  - 
UR  - https://doi.org/10.1071/CH9791943 
N2  - X-ray crystallographic determination of structure has shown that the even-electron product obtained thermally from 5-(10-phenyl-5,10-dihydro-5-phenazinioyl)-1,3-dimethyl-4-barbiturate (1) (e.g. by heating in benzene) has the structure 1,3-dimethy1-5-(10-phenyl-2,10-dihydrophenazin-2-ylidene)- hexahydropyrimidine-2,4,6-trione (3) instead of the previously supposed dehydro dimer structure (2). Crystals of compound (3) are triclinic, P&#299;, a 11·014(3), b 9·343(3), c 10·927(3) Å, &#945; 110·47(4), &#946; 64·99(4), &#947; 101·47(4)º, Z = 2. Full-matrix least-squares refinement gave R 0·09. The rearrangement that occurs in the conversion of the free-radical betaine (1) into the trione (3) is a novel type of N to p-aromatic rearrangement which presumably entails dissociation followed by recombination and oxidation. 
ER  -

