Acridine 9-one

An example of disproportionation to (109) and (110) is provided by the behaviour of the berberinium ion in alkaline solution (Scheme 62). The pseudobase of the 5-methyl-phenanthridinium cation is present even in neutral solution (equation 85). Attack at position 9 in acridinium salts is also very easy, and they rearrange to pseudobases in a few minutes in alkaline solution. These pseudobases, unlike the others described, do not undergo ring opening. They readily disproportionate or are oxidized to acridin-9-ones by air when the starting salt is unsubstituted at C-9 (B-78MI20502). Pyridine 1-oxides and their analogues... 

Pyrolysis of 4-phenyl-l,2,3-benzotriazine 3-oxide (100) at 420 °C gave 3-phenylbenz-isoxazole (101), 3-phenylindazole (102) and acridin-9-one (103). However, the pyrolysis of 4-phenylnaphtho[2,3-. 

Oxidation of 5//-dibenz[7>,/]azepine (12) with Fremy s salt [ON(S03K)2] yields a mixture of acridine-9-carbaldehyde (13) and 2//-dibenz[A,/]azepin-2-one (14).215 The dibenzazepin-2-one 14 is also obtained in 46% yield with bis(trifluoroacetoxy)pentafluoroiodobenzene [PhI(OCOCF3)2] in acetonitrile as the oxidant.221... 

Acridine-9-carbaldehyde (24%) is one of several products formed from the oxidation of 5//-dibenz[A/]azepine with tert-butyl hypochlorite in dichloromethane at — 70 C.229 The reaction is even more complex in the presence of silver(I) trifluoroacetate, and an analysis of the reaction mixture by GC-MS techniques reveals the presence of eleven products, the major ones being acridine (37%), an unidentified 5//-dibenz[/ ,/]azepinecarbaldehyde (23%) and acridine-9-carbaldehyde (9 %). 

Pyridinethiones and thiols are readily oxidized to the corresponding disulfides by reagents such as hydrogen peroxide, potassium ferricyanide and bromine, e.g. Scheme 126 (70JCS(C)1530). Treatment of acridine-9-thione with sulfuric acid gives acrid-9-one. 

Oxidation of 5//-dibenz[6,/]azepines by Fremy s salt has been examined closely. At pH 7.5 the quinonoid dibenz[6,/]azepin-2-one is produced together with acridine-9-aldehyde (74CRV101). 3-Chloro-10,11 -dihydro-5//-dibenz[6,/]azepine yields a mixture of the quinoneimines (174 R=C1) and (175) which with sodium dithionite reduce to the corresponding chlorohydroxydihydrodibenzazepines (76JHC269). 

Acridine, halogenation, 59, 295 Acridine A-oxide, halogenation, 59, 295 Acridine, 9-benzyl-, nitration, 58, 251 Acridine, 9-phenyl-, nitration, 58, 251 Acridin-9(10//)-ones, see Acridones Acridizinium ion, see... 

Bis(2-diethylaminoethoxy) fluoren-9-one or tilorone dihydrochloride and related compounds e.g. - fluorenone ethers - fluorenone esters - fluorene ketones - fluorenone ketones - dibenzofuran ketones - xanthone ethers - anthraquinone ethers - anthraquinone sulfonamides - fluoranthene esters 2. Thiazine and acridine derivatives - Thiazine derivatives in vivo (mice, rats) Late 85-91)... 

Ethyl 2,3-dihydro-l//-benz[Z>]azepin-5(4/ )-one-3-carboxylate has been prepared in a similar manner from ethyl 3-bromomethyl-2,3-dihydroquinolin-4-one-3-carboxylate and 5-methyl-benz[Z>/] azepine may be prepared from acridine-9-carboxylate as shown in Scheme 35 <93TL7709>. 

Trihydroxy-4-methoxy-10-methyl-2,8-Ws(3-methylbut-2-enyl) acridin-9(10//)-one, l,5-dihydToxy-2,3-dimetboxy-10-metbyl-9-acridone, 2,3-Dibydro-4,9-dihydToxy-2-(2-bydroxypropan-2-yl)-l 1-metboxy-10-metbylfuro[3,2-b]acridin-5(10//)-one, 3,4-Dihydro-3,5,8-tribydroxy-6-metboxy-2,2,7-trimetbyl-2/f-pyrano[2,3-a]acridin-12(7//)-one, l-metbyl-2-nonylquinolin-4(l//)-one, 2-(pent-l-enyl)quinoline, 2-nonylquinolin-4(l/7)-one, 2-n-pentylquinoline, 2- -propylquinoline,... 

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