LABORATORY METHODS OF ORGANIC CHEMISTRY BY L. GATTERMANN COMPLETELY REVISED BY HEINRICH WIELAND TRANSLATED FROM THE TWENTY-FOURTH GERMAN EDITION BY W. MCCARTNEY, PH.D.(EDIN.), A.I.C. LATE ASSISTANT IN THE DEPARTMENT OF MEDICAL CHEMISTRY, UNIVERSITY OF EDINBURGH WITH 59 ILLUSTRATIONS IN THE TEXT NEW YORK THE MACMILLAN COMPANY 1937 COPYRIGHT PRINTFD IN GREAT BRITAIN BY B. & R. CLARK, LIMITED, EDINBUMGH PEEFACE TO THE TWENTY-FOUBTH EDITION WHILE the student is being educated in preparative work it is necessary for him to acquire some knowledge of the incessant pro- gress in the methods of organic chemistry and at the same time to become familiar with the most recent results of research work. For these reasons a series of changes had to be made when this new edition was prepared. In order not to increase the bulk of the book these objects have been attained by sacrificing examples {e.g. lino- lenic acid, crystal violet, Gattermann-Koch aldehyde synthesis) with which, from this point of view, it seemed possible to dispense. Of the newly included methods two may be mentioned here : analysis by chromatographic adsorption which has attained such great importance, and the ozonisation of unsaturated compounds by the recently well-developed procedure. The section on analytical methods has been completely re- written because the development of organic chemistry has caused the macro-methods practised in the classic period, methods which required considerable amount of material, to come to be regarded as survivals. The candidate for the Doctor degree, we know, no longer has to acquire the art of carrying out combustions since he is rightly unwilling, in practising this art, to sacrifice relatively enormous amounts of pure substance, often laboriously obtained. On various grounds I doubt the advisability of including micro-analysis in general practical courses. During a period of two years we have obtained such good results in this laboratory with a procedure worked out, on the basis of Pregl's method, by Dr. F. Holscher that I have included it in this book. For this procedure 20-30 mg. of substance are required. The position has been reached where the candidate for the Doctor vi LABOEATORY METHODS OF ORGANIC CHEMISTRY degree who reaps from his investigation a harvest not altogether too scanty and too precious, again carries out himself the com- bustion of his substances. It will be understood that, in working out this " meso-analytical " method now recommended we have made use, not only of the funda- mental principles of Pregl, but also of all practical and tested improvements of other authors. (I propose the term " meso- analytical " instead of the clumsy " half-micro ".) A reprint of the English edition of the book has appeared, and I have by chance learned that it has been translated into Russian and already published in two very large editions in Soviet Russia. An Italian translation is in course of preparation. I again have to thank several colleagues for valuable suggestions. In particular I have to thank Prof. F. G. Fischer, Freiburg, and Dr. Elisabeth Dane, as well as my teaching assistant Dr. G. Hesse, for their active collaboration in the revision of the book. The proofs have been corrected by T. Wieland. HEINRICH WIELAND MUNICH, June 1935 PREFACE TO THE KEVISED (NINETEENTH) EDITION IT is rather more than thirty years ago since Ludwig Gattermann published the first edition of his Anleitung fur das organisch-chemische Praktikum. The plan of providing the preparative directions with theoretical explanations has certainly proved satisfactory. That is already shown by the wide circulation of the book, of which eighteen editions have appeared. Methodology and technique are undoubtedly the chief objects of the practical course, but aiming merely at culinary art and technical achievement such a course does not accomplish enough. A command of methods implies above all an understanding of their rationale and a power of adapting their numerous modifications to particular requirements; the architect is more important than the mason. We demand that the student should be conversant with the theory of the transfor- mations which he carries out practically. The comments made on the individual preparations are intended to facilitate a survey of the subject in hand, and to encourage the use of text-books and journals by further reading. Now that a knowledge of the principles of organic chemistry may be assumed during the pre- parative work in German universities, the danger of such com- ments becoming a pons asinorum is remote. In rewriting the book the theoretical and practical requirements have been deliberately increased. The equipment which sufficed during the last three decades has now become insufficient for those who desire to work at present-day problems, where difficulties have been accentuated alike in pure science and in technology. The idea of making the preparative work at once an explanation and a living experience of the science has demanded a rearrange- viii LABOKATOKY METHODS OF ORGANIC CHEMISTEY ment of the subject matter in accordance with systematic relation- ships. It will be seen that the new arrangement does not depart seriously from the path which ascends from the more simple to the more difficult. In any case a considerable educational advantage may be expected to result from the rounding off of successive sub- jects. The general part as well as the analytical have been completely revised and greatly shortened in order to make more space for the preparative part. The increase in the number of preparations is intended to provide variety, and to counteract a tendency towards stereotyped routine in the organic practical course. I am greatly indebted to my assistants, especially to Drs. Franz Bergel and F. Gottwalt Fischer, for untiring co-operation in carrying out numerous experiments. Dr. Fischer has, moreover, drawn the new diagrams for this edition and has prepared the index. HEINEICH WIELAND FEEIBURQ I. B., Master 1925 CONTENTS A. SOME GENERAL LABORATORY RULES PAGE Reaction Velocity and Temperature 1 Purification of Organic Substances 3 Crystallisation 4 Chromatographic adsorption . . . . . .14 Distillation 15 Sublimation 26 Distillation with Steam . . . . . . .27 Evaporation of Solvents 29 Extraction 32 Working with Compressed Gases 35 Heating under Pressure 37 Stirring and Shaking 38 Determination of the Melting Point . . . . . .40 B. ORGANIC ANALYTICAL METHODS Detection of Carbon, Hydrogen, Nitrogen, Sulphur, and the Halogens . 43 Organic Elementary Analysis . . . . . .46 I. Determination of Nitrogen by Dumas' Method . . .47 II. Determination of Carbon and Hydrogen by Liebig's Method . 55 III. Determination of Halogen, Sulphur, and other Elements . . 69 1. Determination of halogen by the Carius method, p. 69; 2. Argentometric determination of chlorine and bromine, p. 73 ; 3. Iodine determination by the Leipert-Munster method, p. 76 ; 4. Determination of sulphur by the Carius method, p. 77 ; 5. Deter- mination of sulphur by combustion, p. 78; 6. Simultaneous determination of halogen and sulphur, p. 79; 7. Determination of other elements, p. 79. IV. Determination of Organic Groups . . . . .80 1. Volumetric determination of methoxyl and ethoxyl, p. 80; 2. Determination of the acetyl and benzoyl groups, p. 82; 3. Determination of active hydrogen by the method of Tschugaeff and Zerevitinoff, p. 84. V. Determination of Molecular Weight . . . . .86 x LABOKATOKY METHODS OF OEGANIC CHEMISTKY C. PREPARATIVE PART PAGE On the Prevention of Accidents 88 Equipment required by the Beginner . . . . .90 I. THE REPLACEMENT OF HYDKOXYL AND HYDEOOEN BY HALOGEN. ALCOHOLS AND OLEFINES 1. Ethyl bromide from ethyl alcohol . . . . .93 • Methyl bromide, p. 95. 2. Ethyl iodide from ethyl alcohol . . . . . .95 Methyl iodide, p. 96. 3. Benzyl chloride from toluene 100 4. Bromobenzene 103 p-Dibromobenzene, p. 105. 5. Ethylene from ethyl alcohol. Ethylene dibromide . . . 107 6. Glyool from ethylene dibromide . . . . . .114 7. Isoamyl ether . . . . . . . .117 8. Chloroacetic acid from acetic acid and chlorine . . . .118 II. CABBOXYLIC ACIDS AND THEIR SIMPLE DERIVATIVES 1. Acid chlorides 121 (o) Acetyl chloride, p. 121 ; (A) Benzoyl chloride, p. 121 ; Acetanilide, p. 125 ; Benzoyl peroxide, p. 125. 2. Acetic anhydride . . . . . t . .126 3. Acetamide 129 Benzamide, p. 130. 4. Urea and semicarbazide . . . . . . .131 (a) Potassium cyanate by oxidative fusion, p. 131 ; (6) Urea, p. 132 ; (c) Semicarbazide, p. 134; (d) Urea (and uric acid) from urine, p. 135. 5. Nitriles . 137 (a) Acetonitrile, p. 137 ; (b) Benzyl cyanide, p. 137. 6. Hydrolysis of a nitrile to the acid. Phenylacetic acid . . 140 7. Esters 141 (a) Ethyl acetate from acetic acid and alcohol, p. 141, Ethyl benzoate, p. 141 ; (b) Isoamyl nitrite, p. 146, Ethyl nitrite, p. 147 ; (c) Ethyl nitrate, p. 148 ; (d) Hydrolysis of fat or vegetable oil, p. 149 ; Prepara- tion of the free fatty acid, p. 150, Glyoerol, p. 150; Analysis of fats, p. 151. 8. Conversion of carboxylic acids into the next lower amines . .152 (a) The Hofmann reaction. Methylamine from acetamide, p. 152 ; (b) The Curtius reaction, p. 153, Benzoyl azide, p. 153, Phenyl cyanate, p. 153, Phenylurethane, p. 154. CONTENTS x III. NrTRO-COMPOtTNDS AND THEIR REDUCTION PRODUCTS PAG] 1. Nitromethane . . . . . . . 15( Methylamine, p. 158, N-Methylhydroxylamine, p. 158, Methyl- nitrolio acid, p. 158, Silver fulminate, p. 159, Phenylnitroethylene, p. 160. 2. Nitration of an aromatic hydrocarbon . . . . .161 (a) Nitrobenzene, p. 161 ; (b) Dinitrobenzene, p. 162. 3. Reduction of a nitro-compound to an amine 16£ (a) Aniline from nitrobenzene, p. 165, Diphenylthiourea, Phenyl- isothiooyanate, p. 169; (6) ro-Nitraniline from m-dinitrobenzene, p. 171. 4. Phenylhydroxylamine . . . . . . .174 y-Aminopheno], p. 176, Nitrosophenylhydroxylamine, p. 177. 5. Nitrosobenzene . . . . . . . . 17S Nitrosobenzene from aniline and Caro's acid, p. 179, Azobenzene from aniline and nitrosobenzene, p. 181, Azoxybenzene from phenyl- hydroxylamine and nitrosobenzene, p. 182. 6. Hydrazobenzene and azobenzene 183 (a) Hydrazobenzene, p. 183; (b) Azobenzene from hydrazobenzene, p. 184; (c) Benzidine from hydrazobenzene, p. 186. Mechanism of the reduction of nitrobenzene, p. 188. IV. SULPHONIO ACIDS 1. Benzene monosulphonic acid from benzene and sulphuric acid . 191 Diphenylsulphone, p. 191, Benzenesulphonyl chloride, p. 192, Benzenesulphonamide, p. 192, Benzenesulphohydroxamic acid, p. 192. 2. Toluene-y-sulphonic acid 193 3. Naphthalene-/3-sulphonic acid 194 4. Sulphanilic acid from aniline and sulphuric acid . . . 195 5. 2 : 4-Dinitro-a-naphthol-7-sulphonic acid (naphthol yellow 8) . 195 Thiophenol, p. 201. V. ALDEHYDES 1. Formaldehyde 203 Determination, p. 204. 2. Acetaldehyde 205 (a) From ethyl alcohol, p. 205 ; (6) from acetylene, p. 209. 3. Benzaldehyde from benzylidene chloride 209 Paraldehyde, p. 217, Metaldehyde, p. 217. 4. Cannizzaro's reaction. Benzoic acid and benzyl alcohol from Jbenzaldehyde 220 xii LABORATORY METHODS OF ORGANIC CHEMISTRY PAQE 5. Aoyloin condensation. Benzoin from benzaldehyde . . . 222 Benzil from benzoin, p. 222, Benzilic acid, p. 225. 6. Addition of hydrogen cyanide to an aldehyde. Mandelic acid from benzaldehyde 227 7. Alanine 229 8. Perkin's synthesis. Cinnamic acid from benzaldehyde and acetic anhydride 232 Hydrogenation of cinnamie acid, p. 234, Sodium amalgam, p. 234. 9. The Reimer-Tiemann synthesis. Salicylaldehyde from phenol and chloroform 235 ;p-Hydroxybenzaldehyde, p. 236. VI. PHBUOLS AND ENOLS. KETO-ENOL TAUTOMERISM 1. Conversion of a sulphonic acid into a phenol. /?-Naphthol . . 239 Phenyl benzoate, p. 241, Naphthyl benzoate, p. 242, Tribromo- phenol, p. 242. 2. Methylation of phenols 244 (a) Anisole, p. 244 ; (b) /3-Naphthyl methyl ether, p. 244. 3. Ortho- and para-Nitrophenols 246 4. Kolbe's salicylic acid synthesis 249 5. Synthesis of the ester of a /3-keto-acid. Acetoacetic ester . . 251 6. Acetylacetone 252 Benzoylacetone, p. 253. 7. Diethyl malonate 254 Diethyl ethylmalonate, p. 254, Ethylmalonic acid, p. 255, Butyric acid from ethylmalonic acid, p. 255. 8. Phenykutromethane 256 (a) aci-Phenylnitroacetonitrile sodium, p. 256 ; (6) Sodium salt of aci-phenylnitromethane, p. 256. On keto-enol tautomerism 257 The use of ethyl acetoacetate and ethyl malonate for synthetic purposes 264 VII. THE DIAZO-COMPOUNDS General 269 A. Aliphatic Diazo-Compounds 1. Diazomethane . . . . . . . .271 Nitrosomethylurea, p. 271. 2. Ethyl diazoacetate 275 (a) Glycine ethyl ester hydrochloride, p. 275, Hippuric acid, p. 277 ; (b) Ethyl diazoacetate, p. 277. [...]... 289 ; (/) Sodium jj-nitrophenyl-amM-diazotate, p 290 4 23-Tolunitrile from p-toluidine (Sandmeyer's reaction) 291 Benzonitrile, p 292, ^i-Toluio acid, p 292 5 Arsanilic acid from p-nitraniline 293 6 Phenylhydrazine Benzene from phenylhydrazine, p 299 ; Synthesis of indole, p 299 7 Preparation of azo-dyes (a) Helianthine, p 300 ; (6) Congo red, p 302 ; (c) /3-Naphthol orange,... mixture (0° to - 20°), or by a mixture of solid carbon dioxide with ether or acetone (down to -8 0°) Liquid air is generally not required in preparative organic work To prepare freezing mixtures such as are often required, ice, well crushed in an ice mill or metal mortar, is thoroughly mixed by means of a small wooden shovel with about one-third of its weight of rock-salt, preferably in a low, flat-bottomed... of small amounts of substance Widmer, Helv Chim Ada, 1924, 7, 59 VACUUM DISTILLATION 20 Technically the principle of fractional distillation is applied in the manufacture of spirit and in the isolation of aromatic hydrocarbons from the light oil of coal-tar Mixtures of liquids of higher boiling point (above 120°) are first separated by distillation into several fractions of about the same boiling-point... with holes of various diameters In view of its great importance as a method for preparing analytically pure substances, the technique of filtration deserves the special attention of the student of practical organic chemistry The process of pouring the crystals along with the mother liquor on to porous plate and subsequently washing is emphatically to be rejected Already in the preparation of organic substances... be borne in mind that reduction of the concentration to one-half, one-quarter, or one-tenth makes the reaction four, sixteen, or one hundred times as slow PURIFICATION OF ORGANIC SUBSTANCES The substances which form the object of preparative work are usually solid crystalline materials or liquids—occasionally also gases Because of the multiplicity of reactions in which organic substances can take part,... E D E L - C B A F T S 327 334 SYNTHESES ORGANIC R A D I C L E S The Origntard Reaction 1 Preparation of alcohols 337 (a) Benzohydrol from benzaldehyde and phenyl magnesium bromide, p 337 ; (6) Triphenylcarbinol from ethyl benzoate and phenyl magnesium bromide, p 338 2 Synthesis of a ketone from a nitrile Acetophenone 338 xiv LABOKATORY METHODS OF ORGANIC CHEMISTRY The Friedel-Crafts... beaker); the temperature of the bath should be about 20° above the boiling point of the substance The maintenance of the correct heating temperature is of the greatest importance, since if it is raised too much the boiling point of the distillate will be found too high in consequence of superheating In the case of substances of high boiling point where, for preparative purposes, a margin of a few degrees in... i n t s for u s i n g t h e L i t e r a t u r e of O r g a n i c C h e m i s t r y Preparations from t h e Original Literature Table f o r C a l c u l a t i o n s i n t h e D e t e r m i n a t i o n of N i t r o g e n INDBX 4 1 1 acid, 419 422 424 427 xvi LABORATORY METHODS OF ORGANIC CHEMISTRY ABBREVIATIONS The abbreviations of the titles of journals are those employed in British Chemical... small folds with a rounded glass rod or, in the case of larger plates, with the finger-nail When minute amounts of substance (a few hundred milligrammes or less) have to be filtered, small glass plates 0-5 -1 -0 cm in diameter are used as supports for the filter paper These plates are made from thin glass rods by heating one end in the blow-pipe till soft and then pressing out flat on an iron or earthenware... Zeitschrift fur physiologische Chemie A SOME GENERAL LABORATORY RULES Reaction Velocity and Temperature.—Reactions with organic sub- stances take place much more slowly than those which form the subject matter of a course of practical inorganic and analytical chemistry The latter are nearly always ionic reactions, which proceed with immeasurable rapidity, but organic substances usually react much more slowly . p. 192. 2. Toluene-y-sulphonic acid 193 3. Naphthalene-/3-sulphonic acid 194 4. Sulphanilic acid from aniline and sulphuric acid . . . 195 5. 2 : 4-Dinitro-a-naphthol-7-sulphonic acid (naphthol. use of text-books and journals by further reading. Now that a knowledge of the principles of organic chemistry may be assumed during the pre- parative work in German universities, the danger of. of Organic Chemistry . . . 419 Preparations from the Original Literature 422 Table for Calculations in the Determination of Nitrogen . . 424 INDBX 427 xvi LABORATORY METHODS OF ORGANIC