feHrC \MgN(0H):(?H

C H , CH,

■ N eith er th e n itro h y d ro x am ic acid, C24H3,j0 9N2 (A., 1929, 558), nor its oxim ino-derivative (I) undergoes the B eck m an n -W allach change w hen tre a te d w ith

sulphuric acid. A. Co h e n.

P r o d u c t i o n of b e n z a ld e h y d e f r o m b e n z y l c h lo rid e . P . Sc h o r i g i n, I . Ki z b e r, a n d E . Sm o l i-

a n in o v a (J. A ppl. Chem., R ussia, 1930, 3, 721—

726).— W hen boiled w ith aqueous calcium n itra te , benzyl chloride affords benzaldehyde (60— 65% ) an d benzoic acid (10% ). T he presence of alum inium or copper re ta rd s ox id atio n b y th e n itric acid w hich is liberated. F ree n itric acid m a y be em ployed.

Ch e m ic a l Ab s t r a c t s. F o r m a t i o n of t b i o a m i d e s f r o m a c y la te d a ld e - h y d e c y a n o h y d r in s . V II. J . F . O l i n a n d T . B.

J o h n so n (Rec. tra v . chim ., 1931, 5 0 , 72— 76).— Acyl derivatives of alip h atic ald ehydecyanohydrins are best p rep ared b y shak in g to g e th e r m olecular p ro p o r­

tions of th e aldehyde, th e acyl chloride, a n d pow dered sodium or p o tassiu m cyanide w ith crushed ice u n til the odour of th e acyl chloride disappears. Conversion of these deriv ativ es in to th e corresponding thioam ides is best effected by s a tu ra tin g a so lution of th e ac y lated cyanohydrin a n d tricth an o lam in e in alcoholic solution with hydrogen sulphide. U nlike p y rid in e, th e tri- ethanolamine does n o t cause dissociation of th e thio- amide into hyd ro g en sulphide a n d th e p a re n t nitrile.

Thus from th e ap p ro p ria te a cy la ted cy an o h y d rin are prepared (80— 90% yield) : x-benzoyloxy-,

CHPh(OBz)-CS-NH2, m. p. 139°, a n d a-aceioxy-, m . p.

104°, -phenylacetothioamide ; benzoyloxyacetothio- amide, m. p. 103°, a-benzoyloxypropionthioamide, m . p.

104°, and abénzoyloxy-n-butyrthioamide, m. p. 106°.

All these d eriv ativ es are destro y ed b y hydrolysis w ith mineral acids o r alkalis. J . W . Ba k e r.

Isom érisation of b yd roxyald eh yd es. IV . T ransform ation of a-brom o-p-phenylpropalde- hyde and a-hy dr oxy-p-phenylpr op aldehyde. S.

-Da n il o v an d E . Ve n u s- Da n il o v a (J. R uss. Pliys.

Chem. Soc., 1930, 62, 1697— 1711).— a-Brom o-p- phenylpropaldehyde, o b tain e d b y d ire c t b ro m in atio n of hydrocinnam aldehyde, gives a sta b le monoliydrate,

\v ^ ^ a n d a semicarbazone, m . p . 136-5°.

*» hen heated w ith an aqueous suspension of barium carbonate, th e brom oaldehyde is converted into

a -h y d roxy-p-phenylpropaldehyde, m. p. 51-5— 52°, b. p. 120— 121°/4 m m . (oxime, m. p. 123°; sem i­

carbazone, in. p. 136-5° ; osazone, m. p. 137° ; benzoyl d eriv ativ e, m . p. 70°), to g eth er w ith some h ydro- cinnam ic acid. I f silver oxide is used in ste a d of b ariu m carb o n ate, a-hydroxy-p-phenylpropionic acid, in. p. 98°, is also form ed. On oxidation, th e aldehyde yielded a v a rie ty of p ro d u cts, am ong th e m p h e n y l - acetaldehyde, b. p. 88— 89°/12 m m . (sem icarbazone, m. p. 155°), an d a-hydroxy-p-phenylpropionic acid.

W hen h ea ted in alcoholic sulphuric acid solution in a sealed tu b e, th e aldehyde isom erises w ith th e fo rm ­ a tio n of acety lp h en y lcarb in o l, b. p. 130— 132°/13 m m . (sem icarbazone, m . p. 194°), a n d th e corresponding a-diketone, benzoylacetyl, b. p. 113— 115°/13 m m .;

dioxim e, m . p . 238— 239°. T h e carbinol, on tr e a t­

m e n t b y G rig n ard ’s m eth o d w ith m agnesium ph en y l brom ide, yielded (iy-dihydroxy-Py-diphenylpropane, m . p. 103— 104°, w hich gave acetophenone on

o xidation. 31. Zv e g in t z o v.

A c é ty la tio n of o - h y d r o x y - a ld e h y d e s . T. Ma l­

k i n a n d 31. Ni e r e n s t e i n (J. Am er. Chem. Soc., 1931, 5 3 , 239— 242).— T re a tm e n t of salicylaldéhyde, (3-resorcylaldehyde, a n d phloroglucinaldehyde w ith acetic an h y d rid e in presence of e th e r an d p o tassiu m c a rb o n a te gives th e corresponding O -acetyl, diacetyl, m . p. 69°, a n d triacetyl, m , p. 101°, d eriv ativ es. I n absence of e th e r, fo rm atio n of benzylidene a c e ta te occurs. T he triacetylphloroglucinaldehyde of P r a t t a n d R obinson (A., 1925, i, 826; cf. R o b ertso n an d R obinson, A ., 1927, 974) is 2 : 4 : 6-triacetoxybenzyl- idene a c e ta te (H erzig a n d W enzel, A ., 1904, i, 251).

H . Bu r t o n. C o - o r d in a tio n c o m p o u n d s of o x im e s . I I . N ic k e l a n d c o b a lt c o m p o u n d s of o - h y d r o x y b e n z - a ld o x im e . O. L. Br a d y (-J.C.S., 1931, 105— 107).—

N ickel a n d cobalt com plexes of salicylaldoxim e are described. To acco u n t fo r th e a tta c k of its oxim ino- a n d n o t its phenolic h y d ro x y l group on a céty latio n , th e fo rm u la (I) is suggested fo r th e oxim e, w hich h as

( I - )

p H - J j H

l-H < -N -O H

feHrC \MgN(0H):(?H

i H = N U H O--- C6H.t th e phy sical p ro p erties of a co-ordination com pound.

T he corresponding s tru c tu re (II) is ad v an ced fo r th e nickel (and cobalt) com plexes. H . A. Pig g o t t.

2 - H y d r o x y - 4 - m e th o x y - a n d 4 - h y d r o x y - 2 - m e th o x y - b e n z a ld e h y d e s . T. E . d e Ki e w i e t an d H . St e p h e n (J.C .S., 1931, 84— 8 5 ; cf. A., 1898, i, 581; 1922, i, 555).— m -M ethoxyphenol is condensed w ith hydrogen cyanide an d hydrogen chloride in d ry e th e r in th e cold, th e resu ltin g aldim ide h y d ro ­ chlorides (a fte r 24 hrs.) h y drolysed b y a large excess of w ater, a n d th e aldehydes se p a ra te d b y d istillatio n in steam in w hich 2-hydroxy-4-m ethoxybenzaldeliyde alone is v o latile. T he phenylhydrazone, m. p. 158°, p -nitrophenylhydrazone, m. p. 255° (decom p.), a n d semioxamazone, m. p. 242°, of 4-hydroxy-2-m ethoxy- benzaldehyde, an d th e p-nitrophenylhydrazone, m . p.

226-5°, semioxamazone, m . p. 247°, a n d semicarbazone, m. p. 230°, of 2-hydroxy-4-m eth o xybenzalbehyde are

described. “ ' H . A. Pig g o t t.

C a ta ly tic p r o d u c t i o n of a c e to p h e n o n e . I. G.

Lako m k in (J. A ppl. Chem., R ussia, 1930, 3, 555—

572).— A cetophenone is o b tain ed b y in te ra c tio n of acetic a n d benzoic acids in presence of th o riu m dioxide or p re fe ra b ly m anganous oxide. T he q u a n tity of c a ta ly s t used affects th e yield only if th e acid v ap o u rs are nob p re h e a te d . T he y ield is m ax im al a t 6 0 0 °; p re h e a tin g of th e rea ctin g v ap o u rs is recom m ended.

Ch e m ic a l Ab s t r a c t s. A c tio n of o r g a n ic m a g n e s i u m c o m p o u n d s o n a(3 -o x id o -k e to n e s a n d - e s t e r s . E . P . Ko h l e r, N . K . Ric h t m y e r, a n d W . F . He s t e r(J. A m er. Chem.

Soc., 1931, 5 3 , 205—2 2 1).— x-B enzoyl-S-phcnylethyl- eno oxide, p re p a re d b y a m odification of W eitz a n d Scheifer’s m eth o d (A., 1921, i, 868), is c o n v erted b y a n excess of m agnesium p h e n y l brom ide a t th e o rd in ary te m p e ra tu re in to trip h e n y lca rb in o l (phenyl- dietliylcarbinol is produced sim ilarly using m agnesium e th y l brom ide) a n d resinous m aterial. T he rea ctio n involves th e in te rm e d ia te fo rm atio n of benzophenonc, since trip h en y lcarb in o l is also o b ta in e d from m agnes­

ium p h en y l brom ide an d a-benzoyl-P-anisylethylone oxide, w h ilst m agnesium m esitvl brom ide a n d a-acetyl- p-phenylethylene oxide give acetylm esitylene. W hen a-benzoyl-P-phenylethylene oxide is tr e a te d w ith 1 m ol. of m agnesium p h e n y l brom ide a t —10°, a n d th e m ix tu re decom posed w ith ice-cold acid, fiy-oxido-a v.y-triphenylpropyl fiy-oxido-alcohol (I), y ^ P ^ > C H • CPli2■ O II, m . p. 129— 130°, is produced. T h is is unaffected by m agnesium p h en y l brom ide a t -—10°, b u t is c onverted a t th e o rd in a ry te m p e ra tu re in to trip h en y lcarb in o l.

T re a tm e n t of I w ith m e th y l alcohol co n tain in g a little hydrochloric kcid.gives<x.$-dihydroxy-y-7ncthoxy-a.zy-tri- phenylpropane, m . p . 154— 155° (oxidised b y chrom ic a n d acetic acids to m e th y l benzoate an d benzophenone), also p re p a re d b y the. ac tio n of m agnesium phenyl brom ide on p h en y l a-hydroxy-P-m ethoxy-P-phenyl- e th y l k eto n e (dimethylacetal, m . p. 12 2°, o b ta in ed from p h en y l ap-dibrom o-p-phenylethyl k e to n e a n d m eth y l- alcoholic sodium m ethoxide). W h en I is tre a te d w ith a d ilu te solution of p o tassiu m hydro x id e in m e th y l alcohol a t th e o rd in a ry te m p e ra tu re, isom crisation to fiy-oxido-xyy-triphenylpropyl alcohol (II),

^ ^% >CH -C H Ph-O H ; m . p. 103°, occurs. T his is oxidised by chrom ic a n d acetic acids to a.-benzoyl-$$-di- p hm ylethyU m oxide, m . p. 124— 125°, a n d w ith m a g ­ nesium ph en y l brom ide yields dip h en y lacetald eh y d e a n d b e n z liv d ro l: (II)-f-Ph-M gB r— >CPh„:CH-OM gBr + P h -C H O ; P h -C H O + P h -M g B r— >CRPh.,-O M gBr.

T re a tm e n t of I I w ith m agnesium m e th y l iodide gives d ip h en y lacetald eh y d e, benzaldehyde, an d a sm all a m o u n t of p ro b a b ly diplienylacetylphenylcarbinol, m . p. 128°. W hen I I is exposed to air, autoxid- a tio n occurs a n d th e m ain p ro d u c t form ed is th e peroxide, ^ P1'2> C H - 0 - 0 -C H Ph• O H , w hich decom ­ poses a t a b o u t 160° in to benzaldehyde, form ic acid, an d benzophenone, a n d re a c ts w ith m agnesium m eth y l iodide, form ing aa-dipkenylpropylene glycol, m . p.

94— 95°, also p rep a red from e th y l la c ta te a n d a n excess of m agnesium p h en y l brom ide, a n d a-phenyl- e th y l alcohol. D ibrom odibenzoylm ethane re a c ts w ith m agnesium p h en y l brom ide, form ing phenyl

a-bromo-¡3 - hydroxy-^i-diphe nylethyl ketone, m . p. a b o u t 180°

(decom p.), co n v erted b y m ethyl-alcoholic sodium m eth o x id e in to a-benzoyl-p[3-diphenylethylene oxide.

T his reacts w ith m agnesium p h en y l brom ide a n d eth y l iodide, yielding d ip h en y lacetald eh y d e in each case :

£ P1j £ > 0 + R - M g X — ^ C P h d C H -O M g X + B z-R , T he eth y l d ip h en y lg ly cid ate of P o in te t (A., 1909, i, 234) a n d of B ard o n a n d R a rn a rt (A., 1926, 950) is e th y l p p -d ip h en y lp y ru v ate, m. p. 37° (phenylhydr- azone, m . p. 99— 100°; corresponding methyl ester, b. p. 175°/5 m m ., m . p. 75°) ; isom érisation occurs d u ring d istillatio n (cf. T roell, A ., 1929, 171). Crude e th y l d iphenylglycidate, p re p a re d from benzophenone and e th y l ch lo ro ac etate b y D arzen s’ m eth o d (A., 1905, i, 116), is co n v erte d b y m agnesium p h en y l brom ide in to d ip h en y lacetald eh y d e, an d b y d istillatio n w ith steam in to ethyl tx.p-dihydroxy-$$-diphenylpropionate, m . p. 130° (corresponding methyl ester, m . p. 130—

131°). (3[3-Diphenylpÿruvic acid pheny lh y d fazo n e h a s m . p. (block) 245° (decom p. ; lit. 189°). T ri­

phenylcarbinol is also o b ta in e d w hen e th y l (3f3-di- m eth ylglycidato a n d a-phenyl-¡3-nitrophenylglycidate arc tre a te d w ith m agnesium p h en y l brom ide. T here is no evidence t h a t oxido-com pounds form 1 :4 - ad d itiv e p ro d u c ts w ith G rignard reag en ts (cf. B ard o n a n d R a m a rt, loc. cit.)

T he in itia l p ro d u c t of th e reactio n betw een eth y l P P -diphenylpyruvate an d m agnesium p h en y l brom ide is ethyl 'x-hydroxy-a.$$-triphenylprop>ionate, m. p. 118—

120°. T he fu r th e r re actio n p ro d u c ts are jihenyl a-hydroxy-<x$$-irip>henylethyl ketone, m . p. 123°, and ctp-dihydroxy-%y.?jyy-pentaphenylpro2Mne, m . p. ab ou t 190° (decom p.). W hen th e last-n a m ed com pound is h e a te d in acetic acid a m ix tu re of b cnzhydrol and p h en y l ben zh y d ry l k eto n e is o b tain ed ; in absence of th e acid sm all am o u n ts of benzophenone a n d oc(i[3-tri- ph en y leth y l alcohol are p roduced also.

H . Bu r t o n. B e n z o in c o n d e n s a tio n . I n f lu e n c e of th e n a t u r e of r a d i c a l s o n t h e f o r m a t i o n of m i x e d b e n z o in s . M. Ti f f e n e a u a n d (Ml l e.) J . Le v y (Com pt. rend.,

1931, 1 9 2 , 287— 290).— B y th e o rd in ary benzoin condensation benzaldehyde w ith o-m ethoxybenzalde- h yde, anisaldéhyde, piperonal, an d furfuraldeliyde, and anisaldehyde w ith o-m ethoxybenzaldehyde afford ( > 5 0 % yield) only one benzoin, nam ely, benzoyl-o-m ethoxyphenyl- (semicarbazone, m . p. 178— 179°);

p-melhoxybenzoylphenyl-, m . p. 105-5— 106-5°; 3 : 4 - methylenedioxybenzoylphenyl-, m . p . 120° (semicarb­

azone, in. p. 180—182°) ; furfuroylphenyl-, m . p. 135—

136° (semicarbazone, m. p. 192— 193°) ; a n d p -methoxy- benzoyl-o-methoxyphenyl-, m . p. 10 1—102° (semicarb­

azone, m . p. 204°), -carbinol, respectively. B enz­

aldéhyde an d m -m ethoxybcnzaldehyde afford m-meth- oxybenzoylphenyl- a n d benzoyl-m-methoxyphenyl- carbinol, w h ilst anisaldehyde a n d piperonal give p-anisoyl-3 : i-methylenedioxyphenyl- an d 3 : 4r-methyl- enedioxybenzoyl-p-anisyl-, m . p . 98— 99° (semicarb­

azone, m . p . 191°), -carbinol. M ixtures of isomeric benzoins are th u s o b tain ed w hen th e affinities of the tw o a ry l groups are ap p ro x im ately equal.

J . W . Ba k e r. R e a c tiv ity of s u b s t i t u e n t s i n t h e f iv e - c a r b o n r i n g . V. Ja c o b i (J. p r. Chem ., 1931, [ii], 129,

O R G A N IC C H E M IS T R Y . 3 5 5

55— 96).—In te ra c tio n of equim olecular q u a n titie s of 1 : 3-diketohydrindene a n d tere p h th a la ld eh y d e a t 110— 120° gives 1 : 3-diketo-2-\)-aldehydobenzylidene- hydrindenc, m. p. 173°; excess of th e form er gives 2 : 2'-terepkthdlylidenebis-l : 3 -diketohydrindene, m . p.

293°. I n each case a yellow su b stan c e of high m . p.

is also form ed. T he actio n of m agnesium m eth y l iodide on 1 : 3-diketoliydrindene leads to enolisation, and only b y use of a large excess of th e G rignard reagent is 1 : 3-dihydroxyA-meihylindene (or 3-hydr- oxy-\-keto-3-mcthylhydrindene), b. p . 126°/10 m m ., again accom panied by a yellow su b stan ce of high m. p., form ed. T his is d e h y d ra te d w hen h e a te d to 3-keto-l-methylindene (no m . p. given).

The isolation of 5-brom oindene in a crystalline form, m . p. 36°, is described. W ith m agnesium in eth e r i t form s a G rignard re a g e n t only w ith difficulty; th e p ro d u c t c a n n o t be iso lated in a s ta te of p u rity , b u t its fo rm atio n is p roved by reg en eratio n of indene on decom position w ith w a te r or d ilu te acids.

1 : 2 : 5-Tribromohydrindene is o b tain ed as a n u n ­ stable oil b y a d d itio n of brom ine to 5-brom oindene in light petroleum . W ith 10% alcohol i t gives 1 : 5-di- bronio-2-hydroxyhydrindene, m . p. 80-5— 81-5°. I n te r ­ action of indene dibrom ide w ith abso lu te alcohol gives l-bromo-2-ethoxyhydrindene, a n d w ith m e th y l alcohol

\-bromo-2-metlioxyhydrindene. D istillatio n of th e former u n d e r reduced pressure gives 1 -bromoindetie, b. p. 135-5— 136°, oxidised b y d ilu te n itric acid to phthalic a c id ; its c o n stitu tio n is p ro v ed b y its co n ­ version b y m agnesium , followed b y carb o n dioxide, in dry eth e r in to indcne-\-carboxylic acid, m . p. a b o u t 10°, identified by difference. B ro m in atio n of 1-bromo- indene resu lted in a sm all a m o u n t of su b stitu tio n only, no d irect a d d itio n being observed.

D istillation of indene dibrom ide a t atm ospheric pressure gives 3-bromoindene, b. p. 110— 120°/11 m m ., oxidation of w hich w ith d ilu te n itric acid gives p h th a lic acid. A ction of m agnesium in e th e r p re c ip ita te s th e magnesium in d y l brom ide, converted by carb o n d i­

oxide into indenc-3-carboxylic acid, m . p. a b o u t 160°, 3 : 3'-di-indyl ketone, m. p. 235°, a n d indene. U nlike the 1-brom o-com pound, 3-brom oindene rea d ily adds bromine to give 1 : 2 : 3-tribromohydrindene, c o n v erted by 10% alcohol in to 1 : 3-dibromo-2-hydroxyhydrindene, m. p. 90°.

Bromination of indene in a h o t, d ilu te aqueous suspension gives a tribromoindene, m . p. 133-5— 134°, which, from its ox id atio n b y d ilu te n itric acid to a dibromophthalic acid, m . p. 135°, m u st be d ib ro m in ate d in the benzene nucleus. H . A . Pig g o t t.

P o ly m e r is a tio n a n d p y r o g e n ic d e c o m p o s itio n of p h e n y la c e tic a n h y d r id e . I. c y c /o B u ta n e - a - u io n es. p . Ka l n i n (L a tv ij. U niv. R a k sti, 1930, 1 , 468).—A p relim in ary note. D u rin g th e fra c tio n a tio n of phenylacetic an h y d rid e in a v acu u m considerable decomposition occurs, w ith th e p ro d u ctio n of p h e n y l­

acetic acid an d a residue of a re d su b stan ce w hich gives th e reactions of a n a-diketone. T he re d su b ­ stance is considered to be diphenylc;/c?obutane-a- dione, form ed b y u n sy m m etrical p o ly m erisatio n of the enolic form of th e an h y d rid e and elim in atio n of

~ mols. of phenylacetic acid. F . L . Us i i e r.

b B

Sulphonic acid derivatives of naphthaquinone chloroim ines and di-im ines.

W . Sw i e n t o s r a w s k i, A. Pil t z, a n d F . Kr a c z k ie w ic z (Rocz. Chem ., 1931, 11, 40—48).— Potassium $-naphthaquinone-l-chloro- imineA-sulphonale, th e corresponding 1-¿»«»no-deriv­

a tiv e , potassium $-naphthaquinone-2-chloroimineA- sulphonale, a n d a-naphlhaquinonedichloroiinine-Q-sul- phonate are p re p a re d b y h alogcnating th e a p p ro p ria te am ino n ap h th o l- or naplithylenediam ine-sulphonic acid and saltin g o u t th e p ro d u c t w ith p o tassiu m chloride as form ed a t a low te m p e ra tu re.

R . TRUSZKOwsia.

N ew compound of benzaldehyde and anthra- hydroquinone.

II. A. Be a t t y (J. A m er. Chem.

Soc., 1931, 5 3 , 378— 3S0).— A solution of a n th ra - hyd ro q u in o n c in benzaldehyde co n tain in g a tra c e of hydrochloric acid g rad u ally deposits (in absence of oxygen) a compound, C28H20O3, m . p. 2 1 1— 212°

(corr.), p ro b a b ly form ed by elim ination of 1 mol.

of w a te r betw een 2 mols. of benzaldcbyde a n d 1 mol.

of o x a n th ro n e (the ta u to m e ric form of an th rah jx lro - quinone). T h e com pound is conveniently obtain ed w hen a m ix tu re of an th ra q u in o n e, benzoic acid, alcohol, a n d benzaldehyde is exposed to su n lig h t in absence of oxygen, w hereby p h o to -red u ctio n of th e quinone o c c u rs ; th e volatile p ro d u c ts arc distilled w ith steam , a n d th e residue is tre a te d successively w ith alcohol a n d sodium h y p o su lp h ite to rem ove resinous m a te ria l an d u n changed an th raq u in o n e, respectively. T he com pound is h y drolysed b y alcoholic hydrochloric acid to benzaldehyde and an th ra h y d ro q u in o n e . H . Bu r t o n.

Reduction products of the hydroxyanthra- quinones. XII.

G. F . At t r e e a n d A. G.

Pe r i u n (J.C .S., 1931, 144— 173; cf. A ., 1930, 607).—

T he hyd ro x y - an d m eth o x y -9 -an th ro n es (-anthranols) described below are p re p a re d b y red u ctio n of th e corresponding hyd ro x y - o r m e th o x y -an th raq u in o n es w ith stan n o u s chloride a n d hydrochloric acid (cf.

Goodall a n d P erk in , A ., 1924, i, 527).

D e m eth y la tio n of a m eth o x y a n th ra q u in o n e m a y generally be avoided b y a d d itio n of th e reducing ag e n t to a solution in h o t acetic acid an d allow ing to c o o l; p a rtia l d e m eth y latio n m a y be effected d u r ­ ing red u ctio n b y boiling fo r a lim ite d tim e. P ro ­ longed boiling m a y lead to th e re d u c tio n of b o th carbonyl groups. I n th e m a jo rity of cases th e an th ro n e is read ily oxidised b y ferric chloride in alcohol a n d acetic acid to th e corresponding dian- th ro n e, w hich is form ed in v a ry in g yield, o ften ac­

com panied b y th e a n th ra q u in o n e ; i t is suggested t h a t th e la tte r is form ed b y reactio n in th e a n th ra n o l form . I n co m p arativ ely few cases could fu rth e r o x id atio n to th e corresponding d ian th raq u in o n es.

h elianthrones, a n d n a p h th a d ia n th ro n e s be effected (cf. A ., 1924, i, 300; 1925, i, 1160). T he follow ­ ing a re d e s c rib e d : 3-methoxy-9-anthrone, m . p.

108— 109° (by red u ctio n of 2 -m eth o x y an th raq u in o n e w ith copper a n d ' sulphuric acid a t 140° : purified th ro u g h th e anthranyl acetate, m. p. 152— 154°);

3 : 3 '-dimethoxy-9 : 9'-dianthrone, m . p. 215— 217° ; th e dianthranyl diacetate, m . p. 228— 230°, is oxidised b y iodine in p y rid in e to 3 : S '-d im eth o x y d ian th ra- quinone (A., 1925, i, 1160), fu rth e r oxidised by

insol-a tio n in p y rid in e to 2:2/-d im e th o x y n a p h tk a d ia n th ro n e (loc. cit. ) ; 3 : 6-d ih y d ro x y an th ro n e, m . p . 183— 184°

(A., 1882, 975) 3 : 3 ': 0 : G'-tetrahydroxydianthrone, decom p, indef. 270— 300° (hexa-acetyl d eriv ativ e, m . p. 280— 282°); 3 : G-dimethoxyanthrone, m . p . 158— 160° (acetyl d eriv ativ e, m . p . 180— 181°) [by re d u c tio n of th e dimethyl ether, ru. p. 215— 217°, of zsoanthraflavic acid (m ethyl su lp h a te a n d alkali) b y copper a n d sulphuric a c id ] ; 3 : 3 ' : 6 : Q'-tetra- methoxydianthrone, m . p. 242— 243° (diacetyl d e riv ­ a tiv e, m. p. 255— 256°); G-hydroxy-3-methoxyanthrone, m . p. 234— 236° (diacetyl d eriv ativ e, m . p. 197— 199°);

6 : 6' -dihydroxy-3 : 3 '-dimethoxydianthrone, m . p. 292—

295° (tetra-acetyl d eriv ativ e, m . p. 229— 231°).; 3 : 7- d ih y d ro x y a n th ro n e ; 3 : 3 ': 7 : 7’-tetrahydroxydian-throne, m . p. 315— 31S° (hexa-acetyl d e riv a tiv e , d ark en s 290°); 2 : 3 -d ih y d ro x y an th ro n e (A., 1903, i, 840); 2 : 2 ': 3 : 3 '-te tra h y d ro x y d ia n th ro n e [tctra- acetoxy-com pound, m . p . 274— 277° (acetic a n h y d rid e );

2 : 2 ': 3 : ‘.V-lelra-acetoxy-0 : O'-dianthranyl diacetate, m . p. 293— 295° (acetic a n h y d rid e a n d p y r id in e ) ] ; 2 : 3 -dimethoxyanthrone, m . p. 143— 146° (acetyl com ­ p o u n d , m . p. 169— 171°); 2 : 2 ': 3 : G'-tetramethoxy- dianthrone, m . p. 243— 245° (diacetyl d eriv ativ e, m . p.

194— 196°), read ily oxidised b y alk alin e p ersu lp h a te to 2 : 2 ': 3 : '■i'-tetramethoxydianthraquinone, m . p.

290— 291°, w hich is converted b y insolation in a m ix tu re of benzene a n d alcohol in to 2 : 2 ': 3 : 3'- tetramethoxy-helianthrone, m. p . 287— 288°, a n d - naphthad i an throne, th e la st being th e sole p ro d u c t if th e actio n of lig h t is p ro lo n g e d ; 4 : 4 '-dihydroxy- dianlhrone, m. p. 256— 258° (tetra-acetyl d eriv ativ e, m . p. 265— 267°) ; 1 : 5 -d ih y d ro x y an th ro n e (cf. A ., 1902, i, 773) ; 1 : G-dimethoxyanthrone, m . p. 181—

182° (acetyl com pound, m . p. 169— 171°); 1 : 1 ': 5 : 5'- telramethoxydianthrone, m . p. 305— 3 0 7 °: 1-hydroxy- G-methoxyanthrone, m . p. 131— 133° (diacetyl d e riv ­ a tiv e, m . p. 161— 163°); 1 : V-dihydroxy-G : G'-di-mcthoxydianthrone, m . p . 287— 289° (tetra-acetyl d e riv ­ a tiv e , m. p. 250— 2 5 2 °); 1 : G-dimethoxyanthrone, m . p. 196— 197° (by re d u ctio n of clirysazin d im eth y l e th e r b y zinc a n d a m m o n ia ); 1 : 1' : 8 : 8 '-tetra-meth-oxydianthrone, m . p. above 340° ; 1-hydroxy-S- methoxyantkrone, m . p . 183— 185° (diacetyl d eriv ativ e, m . p. 164— 165°); 1 : 1'-dihydroxy-8 : 8' -dimethoxy­

dianthrone, m . p . above 330° (acetyl d e riv ativ e, m . p.

284— 287) ; 3 : 4 -d im eth o x y an th ro n e, m . p . 162°

[acetyl d eriv ativ e, m . p. 146— 148°; methyl ether, m . p. 116— 118° (by m e th y la tio n of 3 : 4 -d ihydroxy- a n th ro n e w ith m e th y l su lp h a te a n d a lk a li; cf. G raebe a n d T hodc, A ., 1906, i, S63 ; p re p a ra tio n of th e d im e th o x y a n th ro n e b y th e se a u th o rs ’ m eth o d is im p ro v ed b y use of p y rid in e as solvent)].

1 -H y d ro x y an th ro n e is n o t affected b y ferric chloride a t 100°. 1-Methoxyanthrone, m . p. i2 9 — 131°, p re ­ p a re d b y use of copper a n d sulphuric acid, differs in m . p. from th e “ 1 -m etlioxyanthrone ” of G raebe a n d B e rn h a rd (A., 1906, i, 865), w hich is p ro b a b ly its m eth y l e th e r ; i t is n o t a c e ty la te d by acetic an h y d rid e a n d p y rid in e, a p ro p e rty t h a t ap p ears ch aracteristic of a-hydroxy- a n d a-m eth o x y -an th ro n es.

1 : V-Dimethoxydianthrone (diacetyl d eriv ativ e, m . p. 290— 291°) is b e st p re p a re d b y a ir o x id a tio n in alkaline m e th y l alcohol ; if m uch alcohol is em ­ ployed 1 : l'-dimethoxydianihxaquinone, m . p . 315—

316°, is form ed, also produced b y o x id atio n of th e d ia n th ro n e w ith iodine in p y rid in e a t 60° ; i t is oxidised b y insolation in acetone to 4 : 4 ’-dimethoxy- naphthadiantlirone a n d -helianthrone, hydrolysed by 40% hydrobrom ic acid a t 180° to 4 : 4 '-dihydroxy- navhthadianthrone, scarlet, a n d -helianthrone, orange- red , all m elting above 360°. A n im proved m ethod of p re p a ra tio n of l-h y d ro x y -2-m eth o x y an th ro n e (Miller a n d P e rk in , A., 1926, 174) is described. I t is oxidised to 1 : 1' -dihydroxy-2 : 2’-dimethoxydian­

throne (tetra-acetyl d eriv ativ e, m . p. 242— 245°) by th e m ethods a lread y described, a n d also by boiling its so lu tio n in nitrobenzene, or b y th o a ctio n of alkali hyp o io d ite in alcohol, or diazo m eth an e in acetone. 4 : 4 ' - Dihydroxy - 3 : 3 ' - dimethoxylielianthr- one, m . p . above 330°, is form ed from th e an th ro n e by th e a c tio n of iodine or arsenic acid in pyridine, o r b y co n tin u ed boiling of its nitrobenzene solution, a n d to som e e x te n t b y a tte m p te d a c é ty la tio n of the d ian th ro n e a t th o b. p. ; it ca n n o t be a c e ty la te d or reduced, b u t is d e m e th y la te d by hydrochloric and acetic acids a t 180° to 3 : 3 ' : 4 : 4 '-tetrahydroxy- helianthrone, m . p . above 360° (3 : -diacetoxy-com­

pound, m . p. a b o u t 325°), w hich possesses poor affinity as a m o rd a n t dye, b u t is su lp h o n a te d by 20% fum ing su lp h u ric acid a t 100° to a product (isolated as crude sodium salt) w ith m ark e d affinity fo r wool, w hich i t dyes in deep reddish-brow n to slate-blue shades. A s causes of th e low tinctorial pow er of th is h y d ro x y h clian th ro n e th e marked ch elatio n of th e a-h y d ro x y l groups, w hich prevents th e fo rm a tio n of a te tra -a c e ty l d eriv ativ e! a n d the absence of a n h y d ro x y l group in th e p-position to th e carb o n y l g ro u p , are suggested, tin c to ria l power O jj being reg ard ed as d ue to a quinonoid q ty p e of m etallic com plex (annexed form ula). O xidation of 1 : 2-dihy- d ro x y a n th ro n e w ith ferric chloride or th e m inim um q u a n tity of nitrobenzene O Caj gives 1 :1' : 2 : 2' ■ letrahydroxydianthr-one [tetra-acetyl d e riv ativ e, m . p. 245—247° (acetic a n h y d rid e a n d p y rid in e )]; excess of th e la tte r, or iodine in p y rid in e, gives 3 : 3 ' : 4 : 4'-tetrahydroxy- h elian th ro n e, c o n v erted b y sulphuric acid a t 160°

in to a su b stan ce iso lated in sm all a m o u n t as acetyl d e riv a tiv e (probably 4 : 4'-d ih y d ro x y -3 : 3'-diacetoxy- n a p h th a d ia n th ro n e ).

A tte m p te d re d u c tio n of 1 :3-dim ethoxyauthra- q u inone w ith co p p er a n d sulphuric acid fails, but zinc a n d am m onia in w a te r or pyrid in e gives (prob­

ably) 10-hydroxy-l : 3-dimethoxyanthranol, m . p . 156—

158°, a n d stan n o u s chloride gives (after acétylation) 1 : 3 -diaceloxyanthranyl acetate, m . p . 154— 155', identified b y hydrolysis to 1 :3-dihydroxyanthrone, also o b tain ed b y red u ctio n of p u rp u ro x a n th in with sta n n o u s chloride. A sta n n o u s chloride reduction of a n th ra ru fin d im eth y l e th e r a t 65° for 3 hrs. gives 10-hydroxy-l : G-dimethoxyanthrone, m . p. 153— 155°.

O x id atio n of 6 -aceto x y -3 -m eth o x y an th ran y l acetate (above) w ith chrom ic a n d acetic acids gives th e acetyl d e riv ativ e, m . p . 194— 196°, of isoanthraflavic acid monomethyl ether, m . p. 283— 285°; th e last-nam ed is also o b ta in e d by o x id a tio n of th e an th ro n e, and

O x id atio n of 6 -aceto x y -3 -m eth o x y an th ran y l acetate (above) w ith chrom ic a n d acetic acids gives th e acetyl d e riv ativ e, m . p . 194— 196°, of isoanthraflavic acid monomethyl ether, m . p. 283— 285°; th e last-nam ed is also o b ta in e d by o x id a tio n of th e an th ro n e, and

W dokumencie British Chemical Abstracts. A. Pure Chemistry, March (Stron 79-84)