MANDELIC ACID (Phenylglycollic Acid), C 8 H 8 O 3 or C 6 H 5 CH(OH) COOH, an isomer of the cresotinic and the oxymethylbenzoic acids.
OH COOH, may be prepared; and the two other known oxybenzoic acids (ortho- and para-) may be converted into benzoic acid.
The diaminobenzene resulting from two of these acids is the ortho-compound; from three, the meta-; and from one the para-; this is explained by the following scheme: CH NH, NH, NH., IAO NH, N / NH HooCCNH, Cooh Nh, W.
Syntheses of the Benzene Ring.-The characteristic distinctions NH NH, r.-NH, [[Cooh Cooh, _ + Nh2 Nh, H., Cooh]] x x x Tri.
Substituted acetylenes also exhibit this form of condensation; for instance, bromacetylene, BrC: CH, is readily converted into tribrombenzene, while propiolic acid, HC: C. COOH, under the influence of sunlight, gives benzene tricarboxylic acid.
OH COOH,when acetoneoxalic ester, CH 3 CO CH 2 CO CO CO 2 C 2 H 5, is boiled with baryta (Ber., 1889, 22, p. 3271).
More important are Kekule's observations that nitrous acid oxidizes pyrocatechol or [I.2]-dioxybenzene, and protocatechuic acid or [3.4]- dioxybenzoic acid to dioxytartaric acid, (C(OH) 2 COOH) 2 (Ann., 1883, 221, p. 230); and 0.
Thus salicylic acid yields n-pimelic acid, [[Hooc (Ch 2) 5 Cooh]], while o-, m-, and p-cresotinic acids, C 6 H 3 (CH 3)(OH)(000H), yield isomeric methylpimelic acids.
2 and 1.6 compounds were identical, then we should expect the two well-known crotonic acids, CH 3 CH: CH COOH and CH 2: CH CH 2 000H, to be identical.
The prism formula also received support from the following data: protocatechuic acid when oxidized by nitrous acid gives carboxytartronic acid, which, on account of its ready decomposition into carbon dioxide and tartronic acid, was considered to be HO C(COOH) 3.
Two acids corresponding to the formula of Kekule and Claus are triphenyl acrylic acid, (C6H5)2C: C([[Cooh) C 6 H]],, and triphenyl acetic acid, (C,H,),C 000H.
' C 6 Hcooh C?H 4`C'p C s H COOH Polymorphism.
From this two chlornitrobenzoic acids [[[Cooh No]] 2 C1= i.
Or aminopropionic acid, CH 3 ï¿½ CH(NH 2) ï¿½ COOH, a-aminobutyric acid, a-aminovalerianic acid, leucin or isobutyla-aminoacetic acid, (CH 3) 2 CH ï¿½ CH 2.
CH(NH 2) ï¿½ Cooh, isoleucin, probably 0-aminocaproic acid, serin or a-amino-(-hydroxy propionic acid, aspartic acid or aminosuccinic acid, HOOCï¿½CH 2 ï¿½CH(NH 2)ï¿½Cooh, glutaminic acid or a-amino-n-glutaric acid,HOOCï¿½ (CH 2) ï¿½ CH(NH 2) ï¿½ Cooh, diaminoacetic acid, a-O-diaminopropionic acid, lysin.
CH(NH 2) ï¿½ Cooh, arginin or guanidine-a-amino-n-valerianic acid, (NH)(NH2)Cï¿½NHï¿½ (CH 2) 3 ï¿½CH(NH 2)ï¿½Cooh, ornithin or aa-diamino valerianic acid, ï¿½ (CH 2) 3 ï¿½ CH(NH 2) ï¿½ Coon, -(3-imidazol propionic acid, [[Hoocï¿½ Ch(Nh 2) ï¿½Ch 2 ï¿½ C: Chï¿½N:Chï¿½Nh]], proline or a-pyrrolidin carboxylic acid, [[Hoocï¿½ Ch.
Nh]]ï¿½CH2ï¿½CH2ï¿½CH2, hydroxyproline, phenyl alanine or phenyl-a-aminopropionic acid, C 6 H 5 ï¿½ CH 2 ï¿½ CH(NH 2) ï¿½ Cooh, tyrosine or p-hydroxyphenyl-aaminopropionic acid, phenyl ethylamine, p-hydroxyphenyl ethylamine, tryptophane or indol aminopropionic acid, A.
CH(NH 2)ï¿½ Cooh) B.
On oxidation with potassium permanganate it yields acridinic acid (quinoline -a-(-dicarboxylic acid) C 9 H 5 N(COOH) 2.
This followed from a study of the decomposition products, there being obtained hemipinic acid (CH 3 0) 2 C 6 H 2 (000H) 2, and a substance which proved to be co - amino - ethyl - piperonyl carboxylic acid, CH 2 O 2 :C 6 H 2 [[Cooh-Ch 2 Ch 2 Nh]] 2.
NK RI CO 2H20 [[Cooh C64 - ?
Krafft, Ber., 1883, 16, p. 3018): C16H33 CH2 CH2.0H->C161-133CH2 CH2.0 CO R-> C16H33CH: CH 2 -j-R COOH; from tertiary alcohols by the action of acetic anhydride in the presence of a small quantity of sulphuric acid (L.
CINNAMIC ACID, or Phenylacrylic Acid, C9H80 2 or C 6 H 5 CH: CH COOH, an acid found in the form of its benzyl ester in Peru and Tolu balsams, in storax and in some gumbenzoins.
Heated with acids or alkalis they hydrolyse to acids: RCN + HC1 + 2H 2 O = R COOH NH4C1.
COOH, the first member of the series of aliphatic monobasic acids of the general formula C.H 2, ,O 2.
The above compounds may be represented as: CH 2 -CH--CH COOH CH 2 -CH-CH'COOH CH2-CH-CH'COOH N'CH3 CH'OH I N 'CH3 C H N CH3 CH2 CH 2 -CH-CH 2 CH2-CH---CH CH2 - C H-CH2 Ecgonine Anhydroecgonine Hydroecgonidine
N 2 COOH, may also be considered as mixed azo derivatives.
One of the most important derivatives of diphenyl, from the theoretical point of view, is diphenic acid or diorthodiphenyl carboxylic acid, which can be obtained from diparadiaminodiphenyldiorthocarboxylic acid, H2N < j - < I > NH 2, or from phenanthrene, the consti Hooc Cooh tution of which it determines.
Cooh, is obtained by the oxidation of milk, sugar, dulcite, galactose, quercite and most varieties of gum by nitric acid.
Lagodzinski (Berichte, 1895, 28, p. 1427) has synthesized alizarin by condensing hemipinic acid [(CH30)2C6H2(COOH)2] with benzene in the presence of aluminium chloride.
Anthragallol is synthetically prepared by the condensation of benAoic and gallic acids with sulphuric acid OH i [[Cooh + I 10h - 2h20+ Hooc /Oh]] or from pyrogallol and phthalic anhydride in the presence of sulphuric acid or zinc chloride.
COOH, and isobutyric acid, (CH 3) 2 CH 000H.
It combines with acetoacetic ester to form the aromatic compound meta-oxyuvitic acid, C 6 11 2 CH 3 OH (Cooh) 2.
Heated with sulphur it forms benzoic acid and stilbene: 2C 7 H 6 0+S = C6HS000H+C6H5CHS, 2C 6 H 5 CHS =2S +C14H12 Its addition compound with hydrocyanic acid gives mandelic acid C 6 H 5 CH(OH) COOH on hydrolysis; when heated with sodium succinate and acetic anhydride, phenyl-iso-crotonic acid C 6 H 5 CH: CH CH 2 000H is produced, which on boiling is converted into a-naphthol C 10 H 7 0H.
Phenyl-azo-carboxylic acid, C 6 H 5 N 2 Cooh, is obtained in the form of its potassium salt when phenylsemicarbazide is oxidized with potassium permanganate in alkaline solution (J.