T o bctvtarae&l to the aoaus'n u ' mrgvsAR, •us i m ov l.-m-sw, SWU.t ISB3S, w.g.l v&h #u=- lieponti All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a com plete manuscript and there are missing pages, these will be noted. Also, if materia! had to be removed, a note will indicate the deletion. Published by ProQuest LLC(2017). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States C ode Microform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106- 1346 3WESTIGATI0NS OF SOME PHYSICAL PROPERTIES OF ORGATCIN COMPOUNDS A Thesis Submitted to the University of London for the Degree of Doctor of philosophy Uy GHAZI ABDUL WAHHAB DERWISH March 1959 (i) ABSTRACT The absorption spectra o f ten organotin compounds were measured in the in fra re d region 2 P 5-15 # 3 /t( 4000-650 ceT ) and in the u ltra vio le t region 200-400 The compounds used were: the homologous series P h^S nC l^ (n - 1,2,3,and 4), tetrabenzyltin, tribe n zyltin chloride, te tra -^ to ly ltin , t et rakis-£-chlorophenylt in * trie th y ltin phenoxide. and N s trie th y ltin phthalim ide» The results have been analysed and discussed in d e ta il and a tentative assignment of many of the normal vib ratio n a l frequencies carried out. Some of the vibrational fin e structures of the electronic absorption bands has been te n ta tive ly assigned. The spectral measurements were carried out on samples in the liq u id or the solid state and. in solutions. The effect of the tin atom on the normal vibrational frequencies of the phenyl, benzyl and ethyl groups seems to be ne g lig ib le and most o f . the normal frequencies fa ll w ith in the range expected fo r hydrocarbons. C ertain variations in some of the norm al frequencies of the homologous series ph^SnC l^^ axe correlated to the number of chlorine atoms attached to tin * No interaction between phenyl, benzyl or ethyl groups attached to the seme tin atom was observed. Evidence from both vib ra tio n a l and electronic absorption spectra of the phenyltin compounds confirm s the form ation of d -p -bond between the -elctronic cloud of the benzene nucleus and the empty outerm ost d -o rb ita l of tin ; and that the electro­ negativity of tin increases in the phenyl compounds in the follow ing order? jPh4Sn / PhjSnCl /phgSnClg ^PhSnCl^ The follow ing electronic configuration nay participate appreciably in determ ining the electronic structure of the phenyltin compounds i S C t " An equation derived from the electrostatic theory fo r the e ffe ct of the inte ra ctio n between the substituent and the ortho-hydrogens o f nonosubstituted benzenes on the U lo-E vibrations was developed which leads to the calculation of group dipole moments which are in good ageeement w ith the accepted values from other methods. T etraphenyltin and- te tra b e n zyltin were prepared by an improved method and a new method fo r the preparation of te tra -^-to ly ltin is described. PREFACE The work described in this Thesis was carried out in the laboratories of the Chemistry Department of Battersea College of Technology under the supervision of the late Dr. F.R, Goss and Dr* J.E. Salmon and the direction of Dr. V.S. Griffiths. The writer wishes to express his most sincere appreciation and thanks for the constant help and encouragement received from Dr* V.S. Griffiths during the course of this work. Sincere thanks are due to Dr. Joan A* Reid for her kind help and advice especially on the preparation of organotin compounds. Grateful thanks are also due to the staff of the Chemistry Department for their most valuable help and advice. (iii) CONTENTS c i L w w M n m w Abstract i preface ii Contents iii General Introduction 1 Part One: A Review of the Physical Chemistry of Organotin Compounds 1*1# Introduction 4 1*2# The Atomic Properties of the Elements of Group IVB 5 1*3. Physical Properties of Organotin Compounds 15 1*4. Organotin Compounds of Quadrivalent tin 35 1*5# Organotin Compounds of Bivalent tin 91 part Two: 11*1. Preparations of Organotin Compounds 107 II*2# Absorption Spectroscopic Measurements 113 part Three: The Infrared Absorption Spectra of Organotin "s Compounds 111*1. Theoretical Introduction 123 111.2. The Infrared Absorption Spectra of phenyltin Compounds 141 111.3. The Infrared Absorption Spectra of Benzyltin Compounds 175 111.4. The infrared Absorption Spectra of Tetra-£-toly1- tin and TetraJds~j>-chlorophenyltin 192 IIXo5<» The Infrared Absorption Spectra of Triethyltin Phenoxide and N:Triethyltin phthalimide 111*6* Genrral Discussion on the Infrared Absorption Spectra of Organotin Compounds Part Four: The Ultraviolet Absorption Spectra of Organotin Compounds IV*1* General Introduction I?*2. The Ultraviolet Absorption Spectra of Phenyltin Compounds IV.3* The Ultraviolet Absorption Spectra of Benzyltin Compounds IV*4# The Ultraviolet Absorption Spectra of Tetra-p- tolyltin and Tetralcis-p-chlorophenyltin IV.5* The Ultraviolet Absorption Spectra of Triethyltin Phenoxide and N:Triethyltin phthalimide IV.6, General Discussion on the Ultraviolet Absorption Spectra of Organotin Compounds ooOoo GENERAL PRODUCTION The chemistry of the carbon-netal bond conveniently involves the three main branches of chemistry# The study of organonetallic conpounds provides a wide field for the investigation of the nature of the chemical linkage, especially the transition from the ionic bond to the covalent bond# The transition from "the metallic to the nonr-metallic properties of the elements is reflected , in most cases, in their organic derivatives# Tin exists in two allotropic modifications, a non-ntallic form, grey tin, stable at ordinary temperature and a metallic form, white tin, stable at elevated temperatures# The former has the diamond structure while the latter possesses a more close-packed metallic structure* This fact is reflected in the chemistry of the tin compounds, for example, tin is capable of forming both salt-like (inorganic) conpounds and covalent (organic)conpounds of remarkable stability. This applies not only to quadrivalent tin but also, to a lesser extent, to bivalent tin* The most powerful tools ,so far developed, for the study of the nature of chemical linkages are the physical methods and in particular those methods which are capable of picturing the molecule as a whole (e.g. X-ray crystallography, electron diffraction etc.) and those which picture the nuclear and electronic notions of the molecule (e«f. absorption spectroscopy etc*)# It was therefore planned to use absorption spectroscopy in the study of the carbon-tin bonds and the halogen-tin bonds in organotin conpounds containing both linkages# The following compounds were chosen for that purpose : the homologous series Ph^SnCl^^ (where n-^1,2,3, and 4), tetrabenzyltin, tribenzyltin chloride, tetra-£~tolyltin, t c t r aki s-p^-chl o ropheny 11 in , trietbyltin phenoxide and N: trie thy It in phthalinide * The work to be described in this thesis falls into four parts, each part being complete within itself•• For the proper understanding of the problems of organotin conpounds and for the logical presentation of the results of the present work an introductory survey of the physical chemistry of organotin compounds is given in part One, covering the developments in 2 the field for the last three decades or so. Part Two gives an outline of the preparations of organotin compounds and techniques and instruments for the spectral measurements. Ah improved method for the preparation of tetraphenyltin and tetrabenzyltin are described, together with a new method for the preparation of te#m-jq-tolyltin. Part Three hnd part Four of the thesis present the results of the infrared and ultraviolet absorption spectroscopic measurements together with detailed analysis of the spectra and discussion of the results* oooOooo A w r m t OP THE PHYSICAL CHEMISTRY OP ORSAHOTIN COMPOUNDS 4 1.1. »||W*HWP»INTRODUCTION » 'lii w IN view of the absence of any treatise on the physical, chemistry of the carbon-metal bond as examplified in the wide field of organo- i . metallic compounds, it was necessary for the proper understanding of the problem in hand to review the existing literature on the physico­ chemical properties of organotin compounds and their place among the analogous compounds of the elements of Group IVB of the Periodic Table. In this respect the recent reviews (71,98,125) on the organometallic compounds of silicon , germanium, and lead have proved of great value# Although a comprehensive survey of the literature for the period 1930-1957 was carried out, references to earlier work have only been inclucfel when they proved relevant to the discussion. The more recent publications have been included whenever possible. ICrause and von Grosse in their book (122) on the organometallic compounds have adequately covered the field of organotin compounds up to 1935* More recent reviews (35, 111, 144, 145) on the subject have concentrated upon the preparative aspects and upon the tabulation of melting and boiling points. Gonsquently in this revieu/no effort will be made to give a comprehensive \ : list of these properties. 000O000 5 1,2. THE) ATOMIC PROPERTIES OF THE EIEMENTS OF GROUP IVB The physical sonstants of the elements C,Si,Ge,Sn, and Fb are given in Table 1 * To interpret the variations in the physical and chemical properties of the elements of Group IV, the electronic configuration of the atoms have to be examined.