Laboratory Manual of Organic Chemistry

ver five years, and dXiring this time have been repeatedly corrected. As our classes grew we found it necessary to keep to a definite list of experiments and all our attention was devoted to these. In order to bridge the gap between the particular reac tion studied and allied reactions, many questions were added. These questions have been made the basis of laboratory quizzing and are meant primarily for the student to use for his own ad vancement in the subject to aid him to become his own teacher. A portion of the questions are on the practical work in the laboratory, that is, on the methods of handling apparatus, etc. Many of them will appear to be perfectly obvious. They are nevertheless, put in since it has been noticed that it is the most obvious point which is most often overlooked. The experiments are, in general, the usual ones found in laboratory manuals, changed of course in accordance with our experience, and they were chosen for their teaching value and for the good all-round practical manipulation involved. There are only a few innovations. Menthone and menthone oxime illustrate typical reactions even though their formulas may seem large to the beginner. Glycocoll is prepared by hydrolysis, thus linking up the chemistry of the proteins with that of simpler compounds. Limonene dihydrochloride has tremendous teaching value, and the synthesis of camphor from pinene gives an opportunity for select work in an enticing field. The methods described give good yields in most cases, but the yield was not the prime reason for choosing any experiment. It will be noticed that there are no directions for preparing IV PREFACE such substances as acetacetic ester, malonic ester, etc. These can advantageously be given in connection with special advanced synthetic work, for example, malonic ester can be prepared as the starting-point in the synthesis of veronal barbital, acet acetic ester and also phenyl hydrazine in the preparation of antipyrine, anthraniiic acid for methyl anthranilate or indigo, ethylene chlorhydrin for novocaine procaine, pyruvic acid for atophan, etc. In the large classes of to-day the beginning student does not any longer have the opportunity of rubbing elbows with the older men and learning from such contact many of the little things about laboratory manipulation which aid materially in the successful outcome of an experiment. For this reason, the first experiments in this book are written up in considerable detail with the hope that after the student has learned how to set up his apparatus in the correct way, he will thereafter follow this practice. For the most part this hope has been realized in this laboratory. All operations are described where they are first used, in the order of the experiments, and afterwards their use only is mentioned, sometimes being cross-referenced, but always fully indexed. Special discussions are included only where it is believed the material cannot be found in the ordinary books which the student has at his disposal. It is assumed that before beginning organic laboratory work students have been prepared with a long course in general chemistry and a short course in qualitative analysis. A shortened organic course is mentioned below which has been designed especially for pre-medical students. A good grounding in organic chemistry is, however, absolutely essential for the study of medicine, and the long course should be taken whenever possible...