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No description available.

Section I of this thesis is concerned with the rearrangement of allylic sulphinate esters to sulphones. Isomerisation of cyclohex-2-enyl toluene-p-sulphinate (1) and several related substituted sulphinates was investigated particularly in ionising solvents such as formamide. The substituted systems, 1-[²H]-cyclohex-2-enyl toluene-p- sulphinate and 3-methylcyclohex-2-enyl toluene-p-sulphinate (2), gave sulphones with the label scrambled between C-1 and C-3. Rearrangement of the conformationally biased esters, cis- and trans-5-t-butylcyclohex-2-enyl toluene-p-sulphinate, was not stereospecific. Sulphinate (1), both diastereoisomers of which reacted at the same rate, rearranged more slowly than did sulphinate (2). Rearrangement of sulphinate (1) in the presence of sodium benzenesulphinate lead to formation of some of the phenyl sulphone. A dissociative mechanism involving ion-pairs is proposed for the rearrangement of the above allylic sulphinates in ionising media. The [1,3] sulphonyl group migration of some allylic sulphones is discussed in Section II. 3-Methyl-3-(p-tolylsulphonyl)- 1-butene rearranged on heating in acetic acidwater (3:2 v/v) containing toluene-p-sulphinic acid or its sodium salt, and in this case slow rearrangement did occur in the absence of such additives. Substituted 3-(p-tolyl-sulphonyl)cyclohexenes rearranged in hot aqueous acetic acid containing sodium toluene-p-sulphonate, but were stable in the absence of added sulphinate. Under these conditions, epimerisation of cis- and trans-5-t-butyl-3-(p-tolylsulphonyl)- cyclohexene occurred at the same rate as deuterium was scrambled between C-1 and C-3 starting with 5-t-butyl-3-[²H]- 3-(p-tolylsulphonyl)cyclohexene. Benzenesulphinate was incorporated in a crossover experiment with 3-(p-tolyl-sulphonyl)cyclohexene. A chain addition - elimination mechanism involving either radicals or radical anions (an S_RN1 process) is suggested for the [1,3] rearrangement of the allylic sulphones under the above conditions. Attempts to develop a stereospecific 5-membered ring annulation procedure involving allylic sulphones are described in Section III. As a model system, 1-(p-tolylsulphonyl)-1-vinylcyclopropane, prepared from 3-(p-tolylsulphonyl)propene, rearranged on flow pyrolysis to 1-(p-tolylsulphonyl)- cyclopentene.

The purpose of this study was to develop an efficient method for the concentration of specific volatile taste and odor compounds produced by a selected aquatic actinomycete. A second purpose was to isolate and identify the specific taste and odor compound present in the highest concentration.

The research described herein is concerned with the synthesis of certain organic compounds which have the amino-oxy grouping and are related in structure to the naturally occurring amines, putrescine, spermidine and spermine.

The purpose of the present work is to study the effects of the trimethylsilyl and trimethylgermyl substituents on the N,N-dimethylamino ring system. Both ground and excited state interactions were studied and their magnitudes determined. The experimental data were then used in conjunction with molecular orbital calculations to differentiate among, and determine the importance of, d-p bonding, hyperconjugation or polarization of the trimethylsilyl group on the ground and excited state bonding.

This paper studies the the synthesis of certain alkoxy compounds of 2,3-dichloro-1,4-naphthoquinone that can be considered chemotherapeutic agents.

Organolitnium compounds have been employed in synthetic worK for many years. However only during the last decade has much progress been made in establishing the mechanistic pathways for the reactions of these compounds.

The objective of this study was to synthesize and characterize new energetic polycyclic "cage" compounds. As part of a program involved in the synthesis of new polynitropolycyclic compounds, 2,6-dinitro-5-methoxy- 7-carbomethoxypentacyclo[5. 3 .0 . 0* • * . CP • i ° . 0* •8]decane has been synthesized. This is a model system which can be used to study (1) the effect of nitro substitution on the photolability of carbon-carbon double bonds and (2) to develop methods for avoiding Haller-Bauer cleavage in cage /3-keto esters when synthesizing polynitro-substituted cage compounds.

A series of C-stannylated monosaccharide derivatives were prepared and their chemistry studied. Derivatives having a hydroxyl group ? to tin, i.e. methyl 4,6-0- benzylidene-2(3)-deoxy-2(3)-triphenylstannyl-?-D-allopyranosides [(1) and (2)] and 6-deoxy-l,2-0-isopropylidene-6-triorganostannyl-?-D-glucofuranose (3, R=Me, 4, R=Ph) were prepared by reaction of appropriate triorgano-tin-lithiums with epoxy sugars. Reactions of 3 with TFA, acetyl chloride, benzoyl chloride, ethyl chloroformate, sulphur dioxide and TCNE produced via elimination, 5,-6- dideoxy-1,2-0-isopropylidene-?-D-xylo-hex-5-enofuranose (15). Methyl-tin bond cleavage in 3, with formation of C-(dimethylhalogenostannyl)- monosaccharides, occurred on reaction with I2, Br2 or Pd(COD)Cl2. The product from the I2 reaction was unstable in solution and gave the elimination product 15. MeLi gave no reaction, and both SnCl4 and ClSO3H gave Me3SnCl and acetone as the only recognisable products. The triphenylstannyl derivatives 1, 2 and 4 underwent phenyl-tin cleavage with electrophiles. The 1,2:5,6-di-0-isopropylidene-3-C-(triorganostannyl)methyl-?-D-allofuranoses [R=Me, (11), Bu (12) or Ph (13)] were prepared by reaction of an appropriate (triorganostannyl)methy1-lithium with a keto-sugar. Substitution to form the C-(iodostannylated) monosaccharide occurred for all compounds on reaction with iodine. No elimination was obtained on reaction of 11 with TFA, deprotection being the predominant route. The elimination product was isolated from the attempted Pd-catalysed coupling of 12 with PhCOCl and from reaction of the methoxymethyl ether derivative 14 (R=Ph) with PhLi. No reaction was observed on treatment of 12 and 13 with organolithium reagents. Derivatives having a hydroxyl group ? to tin, the l,2:5,6-di-0- isopropylidene-3-C-triorganostannyl-?-D-allofuranoses [R=Me (9) and Ph (10)] were prepared via reaction of a triorganostanny1-lithium with a keto- sugar. Compound 9 gave predominant methyltin cleavage with I2, was partially deprotected by TFA and gave the methyl-coupled product, Me-R, on reaction with carbon electrophiles, R-Y, under Pd-catalysis. The triphenyltin derivative 10, decomposed on treatment with TFA, gave no reaction with phenyl-lithium and pheny1-tin cleavage with I2. The ?-alkoxy derivatives, l,2:5,6-di-0-isopropylidene-3-0-(triorgano-stannyl)methyl-?-D-glucofuranose [R=Me (5) and Ph (6)] and (triorgano-stannyl)methyl 2,3:5,6-di-O-isopropylidene-?-D-mannofuranoside [R=Me (7) and Ph(8)] were prepared via alkylation of a free hydroxyl by iodomethyl-triorganostannane. The triphenyl derivatives underwent pheny1-tin cleavage with I2 and TFA, while tin-lithium exchange occurred with PhLi to give a lithiated sugar which was trapped by a variety of reagents. Compounds 5 and 7 gave competitive cleavage of Me-Sn and R*OCH2-Sn bonds on treatment with halogens. Reaction with TFA, acetyl chloride and SO2 gave predominant reaction at the protecting groups and no reaction was observed for benzoyl chloride and ethylchlorofornate. Tin(IV) chloride gave mainly methyl transfer to tin to form MeSnCl3 and the C-chlorodimethylstannyl derivatives. Treatment with Pd(COD)Cl2 however, gave competitive transfer of methyl group and sugar moiety from tin to palladium. The crystal structures of 10, 13 and the iodo-derivative of 12 were determined; and the results of biological testing of 10 and 13 for antitumour activity and 1, 6 and 8 for plant protection properties are reported.