Transcriber's Note: Every effort has been made to replicate this text as faithfully as possible. Some changes have been made. They are listed at the end of the text. Synthesis of 2-methyl-4-selenoquinazolone, 2-phenylbenzoselenazole, and Its Derivatives. DISSERTATION SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY IN THE FACULTY OF PURE SCIENCE OF COLUMBIA UNIVERSITY BY YÜ-GWAN CHEN, M. A. NEW YORK CITY 1922 ACKNOWLEDGMENT AND DEDICATION The following research was undertaken at the suggestion of Professor Marston Taylor Bogert to whose interest and advice this work owes whatever merit it may possess. Y. G. CHEN. CONTENTS Acknowledgment and Dedication 2 Abstract of the Dissertation 4 Purpose of the Research 5 Introduction 7 Pharmacological Review 8 Tinctorial Review 14 Experimental: 16 2-methyl-4-selenoquinazolone Four Methods of Preparation Analysis of Selenium Organic Compounds 2-phenylbenzoselenazole Mononitro Derivative Monoamino Derivative Monoacetyl Derivative Monobenzylidene Derivative An Azo Dye Dinitro Derivative Diamino Derivative Diacetyl and Dibenzylidene Derivatives Dyeing with Azo Dyes Bibliography 25 Vita 28 ABSTRACT OF THE DISSERTATION 1. What was attempted? Attempt was made to study organic selenium compounds of the heterocyclic series in reference to those properties leading to tinctorial and pharmaceutical possibilities. 2. What were the methods of attack? (a) Organic selenium compounds were reviewed and their properties examined critically with those of allied compounds. (b) Some new heterocyclic compounds of selenium were studied and their characteristic properties more closely examined along the desired line. 3. In how far were the attempts successful? The literature was reviewed and classified with reference to the properties under consideration, and new selenium organic compounds were prepared and studied which it is hoped may throw some additional light upon the problem. 4. What contribution actually new to the science of chemistry has been made? (a) Compounds newly made have been shown to exhibit a distinct tinctorial value in comparison with their analogues.