Photochemical nitration by tetranitromethane .33. Adduct formation in the photochemical reactions of 1,2,4,5- and 1,2,3,5-tetramethylbenzene

Butts, CP; Eberson, L; Fulton, KL; Hartshorn, MP; Robinson, WT; Timmermanvaughan, DJ

HERO ID

1949399

Reference Type

Journal Article

Year

1996

Language

English

HERO ID 1949399
In Press No
Year 1996
Title Photochemical nitration by tetranitromethane .33. Adduct formation in the photochemical reactions of 1,2,4,5- and 1,2,3,5-tetramethylbenzene
Authors Butts, CP; Eberson, L; Fulton, KL; Hartshorn, MP; Robinson, WT; Timmermanvaughan, DJ
Journal Acta Chemica Scandinavica
Volume 50
Issue 11
Page Numbers 991-1008
Abstract The photolysis of the charge-transfer complex of tetranitromethane and 1,2,4,5-tetramethylbenzene in dichloromethane or acetonitrile gives the epimeric 1,3,4,6-tetramethyl-3-nitro-6-trinitromethylcyclohexa-1,4-dienes 8 and 9, in addition to products of nuclear nitration 12 and side-chain modification 10, 11, and 13-18. Similar reactions of 1,2,3,5-tetramethylbenzene gave trans-1,3,5,6-tetramethyl-6-nitro-3-trinitromethylcyclohexa-1,4-diene 30 and two isomeric 'double' adducts 31 and 32, in addition to products of nuclear nitration 27 and side-chain modification 26, 28 and 29. The eliminative rearrangements of adducts 8 and 30 to give re-aromatized products in acetonitrile or [H-2(3)]acetonitrile and in [H-2]chloroform are reported. The photolysis of the charge-transfer complexes of tetranitromethane with either 1,2,4,5-tetramethylbenzene or 1,2,3,5-tetramethylbenzene in 1,1,1,3,3,3-hexafluoropropan-2-ol (HFP) gives a marked increase in the yields of ring-nitration products 12 or 27, respectively, reactions presumed to proceed via a nitrosation-oxidation sequence. Reaction of 1,2,4,5-tetramethylbenzene with excess nitrogen dioxide in HFP also results in extensive ring nitration to give 12 and 2,3,5,6-tetramethyl-1,4-dinitrobenzene (25); the latter compound is seen as arising via the 2,3,5,6-tetramethyl- 1,4-dinitrosobenzene (34). Similar reaction of 1,2,3,5-tetramethylbenzene gives ring-nitration product 27 as the major product. X-Ray crystal structures are reported for 2,4,6-trimethyl-1-(2',2',2'-trinitroethyl)benzene (26) and trans-1,3,5,6-tetramethyl-6-nitro-3-trinitromethyl-cyclohexa-1,4-diene (30). (C) Acta Chemica Scandinavica 1996.
Doi 10.3891/acta.chem.scand.50-0991
Wosid WOS:A1996VP25200006
Is Certified Translation No
Dupe Override No
Comments Scopus URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-0347846615&doi=10.3891%2facta.chem.scand.50-0991&partnerID=40&md5=6d62f8d3a6733002bb18ed4a0fa2fe4e
Is Public Yes
Language Text English