Studies on tertiary amine oxides. LXXIII. Substitution of aromatic N-oxides with radicals produced from azo compounds.
作者:TOSHIYASU ENDO、SEITARO SAEKI、MASATOMO HAMANA
DOI:10.1248/cpb.29.3105
日期:——
Treatment of quinoline 1-oxide (1a) with α, α'-azobisisobutyronitrile (AIBN) ordimethyl α, α'-azobisisobutyrate in boiling benzene for 5 h affords 2-(1-cyano-1-methylethyl) quinoline (2a) or 2-(1-methoxycarbonyl-1-methylethyl) quinoline (4) in 31.9 or 24.9% yield, respectively, accompanied with a small amount of quinoline in each case. The 1-oxides of lepidine, 3, 2'-diquinolyl and 4-nitroquinoline (1c, 1d and 1e), and isoquinoline 2-oxide (6) similarly react with AIBN to produce the corresponding α-substituted products (2c, 2d, 2e and 7). The reaction of pyridine 1-oxide (8) gives not only the 2-substituted pyridine (9 : 1.5%) but also the 4-substituted one (10 : 3.0%). On the other hand, the reactions of 1a and 6 with phenylazotriphenylmethane in boiling benzene afford the α-phenyl N-oxides (12 : 17.2% and 14 : 34.5%) and their deoxygenated products (13 : 3.5% and 15 : 2.9%).
将喹啉1-氧化物(1a)与α,α'-偶氮二异丁腈(AIBN)或二甲基α,α'-偶氮二异丁酸酯在沸腾的苯中反应5小时,分别以31.9%或24.9%的产率得到2-(1-氰基-1-甲基乙基)喹啉(2a)或2-(1-甲氧羰基-1-甲基乙基)喹啉(4),同时每种情况下都有少量的喹啉生成。缬氨醇、3,2'-二喹啉和4-硝基喹啉的1-氧化物(1c,1d和1e)以及异喹啉2-氧化物(6)与AIBN反应,同样生成相应的α-取代产物(2c,2d,2e和7)。吡啶1-氧化物(8)的反应不仅生成了2-取代的吡啶(9:1.5%),还有4-取代的吡啶(10:3.0%)。另一方面,1a和6与苯基偶氮三苯甲烷在沸腾的苯中反应生成了α-苯基N-氧化物(12:17.2%和14:34.5%)及其脱氧产物(13:3.5%和15:2.9%)。