The action of nitrogen dioxide and nitric oxide on humulene, C15H24, and humulene nitrosite, C15H24N2O3. Reaction mechanisms and isolation and characterization of reaction products

Abstract

Humulene nitrosite (3), dinitrohumulene (5), and nitronitratohumulene (4) are obtained as crystalline products when nitrogen dioxide and nitric oxide react with humulene. ¹H N.m.r., ¹³C n.m.r., i.r., and mass spectroscopy enable the molecular structures for each of these compounds to be deduced. The yellow oil, obtained when humulene nitrosite reacts with nitric oxide and nitrogen dioxide, contains dinitrohumulene (5), nitronitratohumulene (4), 1,1,4-trimethyl-8-methylene-7-nitrocycloundeca-3,10-diene (9), isomers (11) and (12) of compound (9), the caryophyllene derivative 4,11,11-trimethyl-8-methylene-2,5-dinitrobicyclo[7.2.0]undec-3-ene (10), three nitroxide radicals, and several olefinic compounds derived from further reaction at position C(10)C(11) of the humulene structure with oxides of nitrogen. These compounds originate from reactions in which a ‘master’ aliphatic radical (15) takes part, and their characterization enables details of the mechanisms of reaction of N₂O₃ with humulene nitrosite to be unravelled.