Erfried Pinter

Untersuchungen über Chinone, 10. Mitt. Zur Reaktion vonp-Benzochinon mit sekundären aliphatischen Aminen

Summaryp-Benzoquinone (1) reacts with dialkylamines2a-d to 2-dialkylamino-p-benzoquinones3, 2,5-bis-dialkylamino-p-benzoquinones4, 2-dialkylamino-8-hydroxydibenzofuran-1,4-quinones5, and in pyridine also to 2-dialkylamino-5-p-hydroxy-phenoxy-p-benzoquinones6. A method affording almost exclusively3 has been developed which is also applicable to compounds2e-h.

Zur Synthese und Struktur derp-Indazolchinone und ihrer Methylierungsprodukte Untersuchungen über Chinone, 8. Mitt.

SummaryThep-benzoquinones5e-j react with diazomethane (after dehydrogenation) to 6-anilino-2e, dimethylamino-2h, phenylthio-2i, and methylthioindazolquinone2j. Methylation with dimethylsulfate of these as well as of the already known indazolquinones 6-toluidino-2f, 6-methylanilino-2g, 5-tert.butyl-2m, 5,6-methyl- (isomer mixture)2l,n, and benz-indazolquinone2o yield the 1-and 2-N-methyl derivatives3 and4. The structure of the 2-methyl derivatives is established by reaction of the corresponding benzoquinones with 3-methylsydnon in the case of4e,4g. UV/VIS-, IR- and1H-NMR-spectroscopy (in CDCl3 andDMSO) were used for structure determination. Comparison of the UV/VIS-spectra of2–4 shows that the indazolquinones are existing as 2 H-4,7-diones. For the structure elucidation of the 1- rs. 2-methylderivatives (whichh can be attributed to the methylation products) NMR-spectroscopy is well suited even without knowing the second isomer (solvent-effect). The course of the reaction of quinones with diazomethane and of the methylation reactions of the indazolquinones is discussed.

Reaktion von 2-(N-Alkyl-p-hydroxyanilino)-1,4-benzochinonen Diazomethan. N-(Alkyl-p-hydroxyanilino)-4,7-indazolchinone und ihre isomeren N-Methylderivate

The reaction of N-alkyl-p-hydroxyanilinobenzoquinones1 a–d, its acetylderivatives11–c1 and the methoxyderivative1 a2 with diazomethan yields in dependence on the reaction-conditions the indazolquinones2 a–d, 2 a1–c1 or2a2, the1-methylindazolquinones3 a–d and31–c1, and finally the methoxy-1-methylindazolquinones5 a–d. The 2-methyl-isomeres6 a–d are formed only in small amounts. Methylation of2 a with dimethylsulfate gives5 a and6 a in the ratio of appr 2 to 1. Acetylation of2 a–d with acetanhydride leads to the N−O-acetylderivatives, which are easily hydrolyzed to2 a1–d1 during work up;3 a d yields3 a1–d1. The structures are established by the described crossexperiments and by spectroscopy (UV/VIS, IR, NMR).

1,4-Carbazolchinone ausp-Benzochinon und primären aliphatischen Aminen. Das vermeintliche und das wahre 2-Methylamino-benzochinon

The compound which is obtained in the reaction of 1,4-benzoquinone with methylamine in chloroform was supposed to be 2-methylaminobenzoquinone; actually it is 6-hydroxy-9-methyl-3-methylamino-1,4-carbazolquinone. The structure is proved by spectroscopic methods, through derivates, zinc dust distillation and via synthesis from 2,5,2′,5′-biphenyl-diquinone. A second main product, 2,5-bis(methylamino)quinone, is obtained; varying the reaction conditions shows especially the influence of the solvent. One of the intermediate products is the true 2-methylamino-1,4-quinone. Other substituted 9-alkyl-3-alkylamino-6-hydroxy-1,4-carbazolquinones can be prepared by reaction with the corresponding primary amines.

2-(N-Alkyl-p-hydroxyanilino)-1,4-benzochinone ausp-Benzochinonen und primären aliphatischen Aminen

In acetic (aqueous or chloroform) solutionp-benzoquinones yield with primary aliphatic amines mainly 2-(N-alkyl-p-hydroxy-anilino)-1,4-benzoquinones besides the 2-alkylamino- and 2,5-bis(alkylamino)-quinones. The methyl-, ethyl-,n-propyl-,n-butylhomologues ofp-benzoquinone and the isomer methylderivatives of toluquinone are described. Their structure were established by spectroscopic (UV/VIS, IR, NMR) methods and by synthesis of the methylderivative3 a fromp-benzoquinone andp-hydroxy-N-methylaniline. The influence of other acids on the reaction was studied.

Über Dihydro-3-thioxo-3H-1,2-dithiolo[4,3-d]pyrimidin-5(4H)-one und Dihydro-3H-1,2-dithiolo[4,3-d]pyrimidin-3,5(4H)-dithione Über Heterocyclen, 34. Mitt.

Dihydro-3-thioxo-3H-1.2-dithiolo[4.3-d]pyrimidine-5(4H)-ones (2) give on methylation 4-methylderivatives (2) and tetrahydro-3-methylthio-5-oxodithiolopyrimidinium salts (6) resp.; from dithiones (3) arise 5-methylthio-resp. 5-methylthio-4-methylderivatives (4) resp. tetrahydro-3-methylthio-5-thioxo-dithiolopyrimidinium salts (6). Peracetic acid converts2 to tetrahydrodithiolopyrimidinium hydrogensulphate10. 2 and3, resp. give with phenylhydrazine 3-phenylhydrazones. Tetrahydro-3-methylthiodithiolopyrimidiniumiodides (6) react with amines in presence ofHMPT to 3-iminocompounds.10 gives with methyl ketones and hydrogen acceptors 3-acylmethylendihydro-dithiolopyrimidine-5(4H)-ones.ZusammenfassungDihydro-3-thioxo-3H-1,2-dithiolo[4,3-d]pyrimidin-5(4H)-one (2) geben bei Methylierung 4-Methylderivate (2) bzw. Tetrahydro-3-methylthio-5-oxodithiolopyrimidiniumsalze (6); aus den Dithionen (3) entstehen 5-Methylthio-bzw.5-Methylthio-4-methylderivate (4) bzw. Tetrahydro-3-methylthio-5-thioxodithiolopyrimidiniumsalze (6). Peressigsäure führt2 in das Tetrahydrodithiolopyrimidiniumhydrogensulfat (10) über.2 bzw.3 geben mit Phenylhydrazin 3-Phenylhydrazone; Tetrahydro-3-methylthiodithiolopyrimidiniumjodide (6) reagieren mit Aminen bei Anwesenheit vonHMPT zu den 3-Iminoverbindungen.10 gibt mit Methylketonen und Wasserstoffakzeptoren 3-Acylmethylendihydrodithiolopyrimidin-5(4H)-one.

Untersuchungen über Chinone, 9. Mitt. Über Acetylderivate vonp-Indazolchinonen

SummaryAcetylation of the indazolquinones1a (6-anilino-),b (6-p-toluidino-),c (6-N-methylanilino-),g (6- or 5-methylthio-), andk (benz[f]-) by heating with acetic anhydride yields the 2-acetylindazolquinones4a, b, c, g, andk. Reductive acetylation of the quinones1c, g, h/h1(6/5-methyl),k and — for structure elucidation — their 1-N- (2c) and 2-N- (3c, 3e)-methyl derivatives with acetic anhydride, zink powder, and sodium acetate gives the 1-acetyl-(7c, g, h/h1,k), resp. 1-methyl- (8c), and 2-methyl- (9c, e) diacetoxyindazoles. In case of1k, two diacetyl derivatives were isolated in addition to the already known triacetyl derivative7k, regardless of the conditions chosen. Acetylation of the intermediate product of the reaction from phenylthio-benzoquinone with diazomethane also yields a triacetyl-hydroquinone (7f). UV/Vis, IR, and1H NMR spectroscopy were used for structure determination. Comparison of the UV/Vis spectra of the acetyl derivatives4 with those of1, 2, 3, and of compounds7 with those of analog substituted indazols shows that the acetyl group is located in position 2 with compounds4 and in position 1 with compounds7. By means of1H NMR spectra the position of the acetyl group can be determined by the effect of the carbonyl group on the proton in position3.