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University Microfilms, Inc., Ann Arbor, Michigan MONOMERIC ORGANOSILICON COMPOUNDS This dissertation has been . micro&hned exactly as received 66-3860 CHAPMAN, Dwain R, 1929- MONOMERIC ORGANOSnJCON COMPOUNDS WITH POLYFUNCTIONAL GROUPS. Iowa State University of Science and Technology Ph.D., 1965 Chemistry, organic University Microfilms, Inc., Ann Arbor, Michigan MONOMERIC ORGANOSILICON COMPOUNDS . WITH POLYPUNCTIONAL GROUPS by Dwain R Chapman A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of The Requirements for the Degree of DOCTOR OF PHILOSOPHY Major Subject: Organic Chemistry Approved Signature was redacted for privacy. In Chai^ge of Major Work Signature was redacted for privacy. Head of Major Department Signature was redacted for privacy. Iowa State University Of Science and Technology Ames, Iowa 1965 11 TABLE OP CONTENTS' Page INTRODUCTION , 1 NOMENCLATURE 3• HISTORICAL 5 Cyclosilanes 5 Reactions of Cyclosilanes 6 Reactions of the Silicon-Silicon Bond 12 The Ultraviolet Absorption Properties 21 of Polysilanes Heterocyclic Polysilanes 23 . EXPERIMENTAL 28 Preparation of Cyclosilanes 30 Octaphenylcyclotetrasilane. 30 Decaphenylcyclopentasilane (Ila) 31 Dodecamethylcyclohexasilane 32 % Reactions of Octaphenylcyclotetrasilane 33 Octaphenylcyclotetrasilane with 33 , . phosphorus pentachloride In benzene 33 Tn xylene 33 Octaphenylcyclotetrasilane with 34 phosphorus trichloride (attempted). Octaphenylcyclotetrasilane with . 34 chlorine In carbon tetrachloride 34 In ether 34 In petroleum ether (b.p. 60-70 C) 36 In n-pentane 36 In ether containing hydroquinone ' 36 Ill Octaphenylcyclotetrasllane with anhydrous hydrogen chloride Octaphenylcyclotetrasllane with p,0'-dlchlorodlethyl ether Octaphenylcyclotetrasllane with a hexachlorocyclohexane Octaphenylcyclotetrasllane with ^-butyl chloride In xylene In decalln Dehydrohalogenatlon of t-butyl chloride In decalln (attempted) In £-dlchlorobenzene Octaphenylcyclotetrasllane with 2-chlorobutane Octaphenylcyclotetrasllane with n-butyl chloride (attempted) In xylene In £-dlchlorobenzene Octaphenylcyclotetrasllane with jb-butyl bromide Octaphenylcyclotetrasllane and nitrobenzene a,u)-Octaphenyltetrasilane Derivatives IH,4-Bromooctaphenyltetrasllane and t^butyl bromide 1,1,2,2,3,3,4,4-Octaphenyltetrasilan-lol IH,4-Methyloctaphenyltetrasllane 1,4-Dlpropoxyoctaphenyltetrasilane (attempted) IH,4-Propoxyoctaphenyltetrasilane iy • Condensation of 1,1,2,2,3,3,4,4- octaphenyltetrasilan-l-ol • In 900 formic acid (attempted) In 980 formic acid (attempted) IH,4-Chlorooctàphenyltetrasllane with phenyllithiiam In tetrahydrofuran at room temperature Q In tetrahydrofuran at -30 C In tetrahydrofuran at -70°C 1H,4-Chlorooctaphenyltetrasilane and phenylmagnesium bromide (attempted) lH,4-Chlorooctaphenyltetrasilane and phenylmagnesium iodide (attempted) Reactions of Decaphenylcyclopentasilane Decaphenylcyclopentasilane with phosphorus pentachloride In benzene in a 1:2 molar ratio (attempted) In benzene in a 1:5 molar ratio In 1,1,2,2-tetraohloroethane In carbon tetrachloride Decaphenylcyclopentasilane and 1,1,2,2-tetrachloroethané Decaphenylcyclopentasilane with chlorine In ether Decaphenylcyclopentasilane with hydrogen halides (attempted) Decaphenylcyclopentasilane with organic halides (attempted) . Decaphenylcyclopentasilane with hydrogen chloride at high pressure , Page Decaphenylcyclopentasilane and 63 nitrobenzene Dodecaphenylcyclohexasilane and 65 nitrobenzene (attempted) Hexaphenyldisilane and nitro- 65 benzene (attempted) l,5-Dihydroxydecaphenylpenta8llane 65 1,5-Di-n-Propoxydecaphenylpentasilane 66 1,3-Diallyloxyd e caphenylcyclopentasilane 66 Dodecaphenylpentasilane 67 1,5-Dibromodecaphenylpentasilane with 68 phenylmagnesium bromide Reactions of Dodecamethylcyclohexasilane 69 Dodecamethylcyclohexasilane with 69 hydrogen chloride In benzene (attempted) 69 In petroleum ether (b.p, 60-70°C) 69 (attempted) In chloroform (attempted) 70 In carbon tetrachloride 70 (attempted) In £-dichlorobenzene 70 In xylene 72 In dichloromethane 75 Dodecamethylcyclohexasilane and 76 hydrogen chloride at high pressures In a 1:3 molar ratio 76 In a 1:2 molar ratio 78 In a 1:4 molar ratio . 79 Dodecamethylcyclohexasilane and 83 _t-butyl chloride A 1:4 molar ratio pressure reaction 83 At atmospheric pressure 84 In o-dichlorobenzene 84 vi a,uj-Substituted Polydimethylsilanes 1.4-Dichlorooctamethyltetrasilane with Jb-butyl chloride The characterization of new compounds in the Cl-fSiMeg)^-? series 1-Chloro-lJ1,2,2-tetramethyldi8ilane 1-Chloro-l,1,2,2,3J 3-hexamethyltrisilane 1-Chloro-1,1,2,2,3,3,4,4-0ctamethylt etra- silane l-Chloro-l,l,2,2,3,3,4,4,5,5-decamethyl- pentasilane l-Chloro-l,l,2,2,3,3,4,4,5,5,6,6-dodeca- methylhexasilane 1.5-Dichloro-l,l,2,2,3,3,4,4,5,5- decamethylpentasilane Diphenyl derivatives 1,1,2,2,3,3,4,4-Octamethyltetrasilane 1,1,2,2,3,3,4,4,5,5-Decamethylpenta- . silane Preparations and Reactions of Heterocyclic Polysilanes Octaphenyloxatetrasilacyclopentane Octaphenyloxatetrasilacyclopentane with phosphorus pentachloride In 1,1,2,2-tetrachloroethane In benzene Octaphenyloxat etrasila cyclopentane with chlorine Hydrolysis of l-chloro-3-(chlorodiphenyl- siloxy)-l,1,2,2,3,3-hexaphenyltrisilane (XII) vii Octaphenyl-1,3- and 1,4-dloxaoota- phenyltetrasllacyclohexane l-Chloro-5-(chlorodiphenylsilyl)- 96 1,1,3,3,5,5-hexaphenyltrlsiloxane 1.6-Dlchloro-l,l,3,3,4,4,6,6-octaphenyl- 96 2.5-dioxa-l,3,4,5-tetrasllahexane In petroleum ether 96 In n-pentane 97 In carbon tetrachloride- 98 petroleum ether Hydrolysis of l-chloro-5-(chlorodiphenyl- 99 8llyl)-l,l,3,3,5,5-hexaphenyltrisiloxane (Xltl) At 30-40°C qq At 98°C 99 Hydrolysis of l-(diphenylpropoxysilyl)- 101 1,1,3,3,5,5-hexaphenyl-5-propoxytri- siloxane (XVI) The pyrolysis of l-(diphenylpropoxysilyl)- 102 1,1,3,3,5,5-hexaphenyl-5-propoxytri- 8iloxane (XVI) Hydrolysis of l,6-dichloro-l,l,3,3,4,4- 102 6.6-octaphenyl-2,5-dioxa-l,3,4,6- tetrasilahexane (XIV) With hydrogen chloride 103 1.7-Dichloro-l,1,3,3,5,5,7,7-octaphenyl- 104 tetrasiloxane In carbon tetrachloride-petroleura 104 ether In petroleum ether 104 Octaphenylcyclotetrasiloxane 105 Octaphenyloxatetrasilacyclopentane (iVa) 106 with nitrobenzene 0ctaphenyl-l,3-dioxa-2,4,5,6-tetrasila- 108 cyclohexane with nitrobenzene viii Octaphenyl-1,4-dioxa-2,3,5,6-tetra- silacyclohexane with nitrobenzene DISCUSSION The Chlorination of Perphenylated Cyclosilanes The Chlorination of Heterocyclic Polysilanes The Oxidation of Polysilanes with Nitrobenzene The Hydrohalogenation of Octaphenyl- cyclotetrasilane The Hydrohalogenation of Decaphenyl- cy cl op ent a s il an e The Hydrohalogenation of Dodecamethyl- cyclohexasilane Some Observations on a,u)-Polydiphenyl- silane Derivatives Suggestions for Further Research SUrmRY LITERATURE CITED ACKNOWLEDGEMENTS INTRODUCTION Previous interest in organosllicon chemistry has been largely dominated by certain polymeric compounds containing alternate silicon atoms such as the so-called silicones. Studies of the chemistry of silicon have dealt with relatively few compounds containing more than two silicon atoms bonded to each other. However, in recent years technical skills have enabled investigators to prepare and characterize an in­ creasing number of polysilanes of chain lengths seemingly limited only to the present skill and modes available. At the time this investigation was begun several organic substituted cyclosilanes had been characterized and were readily available. Some investigations had been made in the use of these compounds as precursors to formerly unavailable organosllicon compounds. Only a few heterocyclic compounds containing silicon-silicon bonds had been prepared and little or no study had been made of the reactions of these compounds. It had been observed that the presence of a silicon atom in a cyclic compound gave a reactivity to that compound unlike analogous linear compounds. It had also been demonstrated that the reactivity with certain reagents was dependent on ring size. The present investigation was begun to make use of some readily available cyclosilanes and heterocyclic polysllane compounds in a further investigation of their reactivity and. 2 if possible, to initiate.studies of linear polysilanes con­ taining various functional groups by heretofore unused or unknown routes. Such new compounds afford the opportunity of expanding- the present knowledge of the physical properties as well as contributing to the spectrographic studies of organ- opolysilane compounds. Attention was directed toward the ultraviolet and infrared properties of compounds containing the silicon-silicon bond. 3 NOMENCLATURE^ In naming organosilicon compounds having silicon chains, the rules of nomenclature recommended by the Commission of Nomenclature of Organic Chemistry of the I.U.P.A.C., and adopted by The American Chemical Society (l), will be used. However, Rule 70.15 of the so-called Amsterdam report, which, enables us to give the compound Cl-SiPhgSiPhg-O-SiPhgSiPhg-Cl the name 1,5-dichlbro-l,1,2,2,4,4,5^5-octaphenyl-3-oxapenta- silane, also carries the footnote "This rule is subject to the possible extensions of the oxa-aza convention which are* now being considered by the commission". The I.U.P.A.C. Commissions on Nomenclature of Organic Chemistry and of Inorganic Chemistry held joint sessions in 1962 and 1963 and it was tentatively decided that the names of all structures should be based on the name of the corre­ sponding hydrocarbon even when there is little or no carbon present. Following this change, the name for the above com­ pound would be 1,5-dichloro-l,1,2,2,4,4,5^5-octaphenyl-3-oxa- 1,2,4,5-tetrasilapentane. ^The author is
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