摘要:

Org. 567 Anthraquinone Dyes. Part V.l A Contribution to the Study of the Marschalk reaction. Nuclear Methylation of 1 -Aminoanthraquinone Leuco-derivative By L. HavliCkov6 (Mrs.), and J. Arient," Research Institute of Organic Syntheses, Pardubice-Rybitvi, Czecho- sl ova kia 1 -Amino-2-methylanthraquinone is obtained by the action of formaldehyde on the 1 -aminoanthraquinone vat followed by oxidation of the reaction mixture with air. The dependence of the amount of a transient 2.2'-methylene- bis- (1 -arninoanthraquinone) produced upon the conditions is studied. A reaction mechanism is suggested. IN 1936 Marschalk 293 reported the introduction of an alkyl group into the 2-position in 1-amino- or l-hydroxy- anthraquinones, and into the 1-position in 2-hydroxy- anthraquinone by the action of an aldehyde on amino- ,or hydroxy-anthraquinone vats, i.e. aqueous alkaline solutions of the leuco-derivative sodium salts of the corresponding anthraquinones.This reaction is doubt- less related to the Lederer-Manasse reactions. Accord- ing to Brockmann and Miiller a hydroxymethyl deriva- tive is formed transiently in the reaction with formalde- hyde, and reduced with the excess of reducing agent one with formaldehyde. With the optimum initial ratio [1-aminoanthraquinone (1 mol.) ; formaldehyde (2 mol.), sodium dithionite (2 mol.), and sodium hydroxide (13.5 rnol.)] 90% of the 1-aminoanthraquinone reacts in 5-10 rnin. The decrease in 1-aminoanthraquinone does not, however, correspond to the increase in l-amino- 2-methylanthraquinone.7 At the start of the reaction, transient products begin to be formed in addition to some 1-amino-2-methylanthraquinone; the ratio of the products depends on the composition of the original mixture.The decrease in the amount of the transient u U SCHEME 1 (sodium dithionite). We have not, however, suc- ceeded in preparing this transient product, since reduc- tion of 2-hydroxymethyl-1-nitroanthraquinone yields 1-amino-2-methylanthraquinone as the only product. This fact also makes it doubtful that 1-amino-2-hydroxy- methylanthraquinone is continuously present in the reaction mixture. suggests that formation of the methyl derivative is explicable in terms of the existence of tautomeric forms of the amino- and hydroxy-anthra- quinone leuco-derivatives, which would combine with formaldehyde to form methylene-substituted compounds of type (111).In the light of this we suggest the mechan- ism shown in Scheme 1 for the formation of l-amino- 2-methylanthraquinone (IV) . We have studied the dependence of the composition of the reaction mixture upon the initial ratio of the components for the reaction of leuco-l-aminoanthraquin- t All anthraquinones are present in the reaction mixture as leuco-derivatives, from which they are regenerated by oxidation with air. 1 Part IV, J. Arient, J. Slosar, V. Stgrba, and K. Obruba, J . Chem. Soc. (C), 1967, 1331. Voroicov products, after the first 5-10 min., corresponds to the increase in the amount of 1-amino-2-methylanthraquin- one (Figure 1). 2,2'-Methylenebis-( l-aminoanthraquin- one) (V) was shown to be the main by-product by chromatographic and elemental analysis.Its formation can be accounted for either by the reaction of formalde- hyde (1 mol.) with the original quinone (2 mol.), meso- merically assisted by the amino-group, or by a Michael- type addition of the original quinone to the methylene derivative (111). 2,2'-Methylenebis-( 1-aminoanthraquinone) (V) can be vatted without change, but is quantitatively converted into 1-amino-2-methylanthraquinone under the condi- tions of the Marschalk reaction. An attempt to methyl- ate with an insufficient amount of formaldehyde pro- duced evidence in favour of the predominant or perhaps unique formation of 1-amino-2-methylanthraquinone * C. Marschalk. F. Koenig, and N. Ourousoff, Bull. SOC. chim. Fmnce, 103G, 3, 1645.C. Marschalk, Bull. SOC. chim. France, 1939, 6, 655. H. Brockman and E. Miiller, Chem. Ber., 1958, 91, 1920. N. N. Voroicov, ' Zhklady Syntesy Polotovard a Barviv,' SNTL, Praha, 1958, p. 496.568 detriment of the by-product throughout the experiment. siderable decrease in the amount of the original sub- stance was observed, while both products exhibited an increase (Figure 2). If more formaldehyde was added after 60 min., a con- 50 Use of an excess of formaldehyde, however, makes the content of transient product decrease gradually through- 1-aminoanthraquinone (1 mol.) the content of transient product decreased from 70 to 55% between 5 and 150 s out the reaction. With formaldehyde (5 mol.) and 0 J. Chem. SOC. (C), 1970 3 - 2 . 1 through the transient product.Only one half of the introduced formaldehyde can react with l-amino- anthraquinone, because it is converted into formaldehyde 50 s 0 1 30 60 90 l i m e (min.] FIGURE 1 Methylation of leuco-1-aminoanthraquinone with formaldehyde [basic experiment : aminoanthraquinone (1 rnol.), formaldehyde (2 rnol.), sodium dithionite (2 mol.), sodium hydroxide (13-86 mol.)] : 1, 1-aminoanthraquinone ; 2 , 1-amino-2-methylanthraquinone ; 3, by-products (total 100%) bisulphite and formaldehyde sulphoxylate in the presence of sodium dithionite. The former decomposes and reacts with 1-aminoanthraquinone ; the latter is stable even in hot alkali,6 and we have shown that it does not methylate 1-aminoanthraquinone in the vat. On addition of formaldehyde (1 equiv.) to the I-aminoanthraquinone 55% between 5 and 150 min.was observed (Figure 3). In both cases as well as in the basic experiment the amount of the original substance shows an immediate drop to less than 10%. Use of a smaller amount of sodium hydroxide (8.5 mol.) gives similar results (Figure 4). However, addition of more sodium hydroxide during this experiment caused conversion of transient product into 1 -amino-2-met hylant hraquinone (Figure 5). 50 s 0 30 60 90 Time (min.) FIGURE 2 Basic experiment but with formaldehyde (I moI.) initially and formaldehyde (1 mol.) added after 60 min. Similarly, the addition of sodium hydroxide in the course of the experiment with an excess of formaldehyde caused conversion of transient product into final productOrg. 569 EXPERIMENTAL l-A mino-2-methylanthraquinone (IV) .-l- Aminoanthra- quinone (1-56 g.), m.p.256" (from propan-1-01), was added to a solution of sodium dithionite (4-42 g . ) in 30% sodium hydroxide (9-7 ml.). The mixture was stirred at 40" for 30 min., then aqueous 35% formaldehyde (0.55 ml.) was added. The mixture was stirred for a further 5 hr. at 40°, then air was passed through i t and the product was filtered off, washed with water, and dried to give 1-amino-2-methyl- anthraquinone (> 90"/o) , m.p. 200' (lit.,' 20G205°). It is advantageous to carry out the reaction under nitrogen. Methylation of l-Aminoanthraquinone with Formaldehyde in the Vat.-The procedure just described (nitrogen atmos- phere) was employed to study the dependence of the methyl- ation on the conditions.Samples (5 ml.) were removed 2, 5, 10, 30, 90, and 150 min. after the addition of formalde- hyde, and added to a mixture of 30% hydrogen peroxide (2.5 ml.) and water (7.5 ml.). The precipitate was filtered off, washed, dried, and subjected to t.1.c. on alumina [light petroleum-acetone (3 : l)]. The contents of l-amino- anthraquinone and l-amino-2-methylanthraquinone were determined colorimetrically. The following amounts of reagents (related to aminoanthraquinone) were used : sodium hydroxide 8.5, 11, 13.85, 19.85, and 26.4 mol.; formaldehyde 1, 2, 5, 10, and 20 mol.; sodium dithionite 2, 3, and 4.5 mol. Only one of the values was modified, the remainder agreed with the basic procedure [formalde- hyde (2 mol.), sodium dithionite (2 mol.), sodium hydroxide (13.85 rnol.)].IZF values : l-aminoanthraquinone 0.66, l-amino-2-methylanthraquinone (IV) 0.70, 2,2'-methylene- bis-( 1-aminoanthraquinone 0.46. 2-Hydroxymelhyl- l-nitroanthraquinone .-2-Bromomethyl- 1-nitroanthraquinone 8 (3-39 g.) was dissolved in dimethyl sulphoxide (210 ml.) by warming, water (100 ml.) was added, and the solution was boiled for 6 hr., cooled, and filtered. The product was precipitated with water (200 ml.) and gave l-amino-2-methylanthraquinone upon reduction with sodium sulphide or regeneration from the vat as red needles (2.7 g . ) , m.p. 229-230' (from toluene) (Found: C, 63.6; H, 3.4; N, 5.0. CI5H,NO5 requires C, 63-6; H, 3.2; N, 4.95%). 2,2'-MethyZenebis- ( l-aminoanthraquinone) (V) .-This com- pound was separated from the mixture of aminoanthraquin- one derivatives on an alumina column (benzene eluant) to give a red solid, m.p. 220-221' (from benzene), insoluble in camphor and cyclopentadecanone (Found: C, 75.95; H, 4.6; N, 6.05. C2,H,,N204 requires C, 75.95; H, 3-95: N, 6.1 yo). s 5 0 / U 30 60 90 Time (min.] FIGURE 4 Basic mperiment but with sodium hydroxide (8-5 mol.) Time (min.) FIGURE 5 Basic experiment but with sodium hydroxide (8.5 mol.) initially and sodium hydroxide (8-6 mol.) added after 60 min. I 30 60 90 Time (rnin.) 0- FIGURE 6 Basic experiment but with formaldehyde (20 ml.) initially and sodium hydroxide (13.86 mol.) added after 60 min. No reaction of the amino-group was observed in any of the methylations carried out, in contrast to alkylations with some aldehydes of higher molecular weight, which will be the subject of a later report. 7 G. D. Wood and A. T. Peters, J . Ckem. SOC., 1962, 3373. 8 A. Locher and H. E. Fierz, Helv. Chim. Ada, 1927, 10, 642. We thank Mrs. KmonXkovA, for co-operation, Dr. K. Obruba and his collaborators for the quantitative chromato- graphic analysis, and Ing. Synek and his collaborators for elemental analyses. [9/676 Received, April lst, 1969

ISSN:0022-4952    

DOI:10.1039/J39700000567

出版商:RSC    

年代:1970

数据来源: RSC