A major problem confronting every investigator who works with synthetic organic chemistry is that of the crystallization of the products obtained. This problem necessitates extensive attention both on the experimental and on the theoretical level. In order to gain an understanding of the behavior of substances in the liquid state, so as to be better able to manipulate them in procedures intended to induce crystallization from complex mixtures, considerable attention has been given to various models of the liquid state. An understanding of the nature of pure liquids would seem to be an essential prelude to any attempt to understand the behavior of complex mixtures from which one component is to be separated. Since viscous liquids are sometimes in a state of incipient crystallization, or else represent systems which especially resist crystallization (e.g., sirups, glasses, etc.), a study of the capillary behavior of such liquids is of theoretical as well as practical interest. Aside from the insight into the microscopic structure of liquids which may be gained from theoretical interpretations of viscosity measurements, knowledge of viscous flow properties is important in many hydrodynamic problems. The viscosities of solutions of high polymers depend upon the sizes and shapes of the molecules in solution and thus provide a useful method for the study of polymer configurations.

The electrochemical technique of polarography was used to study the complexions formed by Ni(II) ion and pyridine compounds. It was of interest to vary the substituent group on the pyridine ring in order to observe the effects on the nickel - nitrogen coordinate bonds.

It has been found that there exist certain crystalline aluminosilicates which provide regular net-works of channels with diameters no bigger than those of molecules. Such crystals can act as sieves (thus the name "molecular sieves" now marketed by the Linde Air Products Company) and bring about a separation of molecular species by occluding small molecules while not adsorbing larger molecules or molecules with shapes that do not "fit." The aluminosilicates were termed zeolites first by Baron Cronstedt (1) some 200 years ago. He observed that certain mineral crystals, when heated, appeared to melt and to boil at the same time. Thus, from the Greek "zeo," to boil, and "lithos," stone, Cronstedt coined the term "zeolite." The use of zeolite (molecular sieves) has increased during the past several years. The earlier work (1930- 1950) involved the study of the naturally occurring zeolites. During the last ten years the activity has been concerned with the use of synthetic crystalline zeolites in separating both gaseous and liquid components by the molecular sieve action,

It is surprising that no one has considered that coordination might have some effect on the strength of the acid group. It is the intent of this study to fill this gap in the knowledge of amino-acid chemistry. At about the time this study began on the effect of chelation on the strength of the uncomplexed acid group, the next two higher homologs of these dicarboxylic amino acids became commercially available. It was, therefore, decided that the problem of this research should be expanded to include all four of the acidic amino acids. The research problem was also defined to include the systematic synthesis of the platinum and palladium (II) complexes of the four available alpha amino dicarboxylic acids, [see PDF]. Platinum and palladium were chosen since in the +2 oxidation state they were known to form only square planar compounds.

The purpose of this research was to measure fluorescence decay-times of several biologically significant compounds. Although various equations are available which permit one to calculate fluorescence lifetimes from spectral data, ample evidence exists which indicates such calculations are at considerable variance with experimental results.

The initial program of study for consideration was the extension of cyclooctatetraene complexation to other metals of the transition group. Compounds of (COT) with iron, cobalt, chromium, molybdenum, and tungsten which have been reported in the literature involve carbonyl ligands simultaneously as (COT)M(CO)x with x = 2,3----; only Ag(I) as AgN03 adducts are known. Rhodium (I) is said to form an unstable dimer while ruthenium (I) forms a polymer. (COT)Pt(II) chloride, bromide and iodide have been reported but only the iodide has been studied; only (COT)PdCl2 has been reported recently. It was further conceived that substituted (COT) would present a good comparison a ligand especially if steric inhibition of pi-bonding were to be observed. The second phase of the study was limited to platinum (II) and palladium (II) chloride and bromide, owing to the known greater stability of the platinum and palladium complexes; attempted investigation with other metals proved fruitless. The following olefins were chosen for their availability and for the fact that each of these is an eight carbon olefinic system and hence can be considered as an extension of the (COT) system. a. 1,5-cyclooctadiene 1,5-(COD) b. 1,3-cyclooctadiene 1,3-(COD) c. 4-vinylcyclohexene 4-(VCR) d. cyclooctene (COC) Though 1,5-(COD) had been reported as a ligand, the literature records few data on its complexes. The choice of 1,3-(COD)--the isomer of 1 ,5-(COD)--as a ligand posed interesting stereochemical problems in that if both double bonds of this system were employed in pi-bonding to the same metal atom it would produce a distortion of the perpendicularity requirement. On the other hand, 1,3-(COD) offers a conjugated system which might conceivably enhance stability of an over-all pi-bonded system. The other possibilities, of course, would be the use of only one ring olefin per metal atom as: [see PDF file for the chemical bond] Finally, each ring might form a bridge system between two metal atoms. This would be possible if the -MX2 planes were perpendicular rather than coplanar [see PDF file for the chemical bond] In any event there is no mention in the literature on the use of 1,3-(COD) as a ligand except by Cope, Stevens and Hochstein (1950) who prepared a silver nitrate adduct 1 ,3-(COD)· 2AgNO.3 4-vinylcyclohexene provides two olefin systems. Would this hydrocarbon behave as a diolefin or would there be exhibited a preference in pi-bonding of one olefin site over the other? Many possible combinations could be conceived; some of which are shown below. [see PDF file for the chemical bond] The inclusion of cyclooctene in the study was made because the only other cycloalkene reported in the earlier literature was cyclohexene. Only an unstable adduct AgNO3• (C8H14)2 was reported by Jones (1954). Recently a compound with the trans form of cyclooctene was made by Cope (1963). [See PDF file for the chemical bond] This compound exists as diastereoisomers and subsequently was resolved into two optically active forms. In the program of study carried out in this research ciscyclooctene was used exclusively. Not only was it the object of this research to attempt the preparation of the olefin complexes, but also to determine something of their chemistry, such as, thermal stability, displacement reactions and the character of their absorption spectra in the visible, ultraviolet and infrared regions. It was intended to extend the often made comparison of platinum chemistry with that of palladium. Toward the end of this research, one other olefin 1,5,9-cyclododecatriene was employed in a limited investigation because of its triple unsaturation; inspection reveals its relation to 1,5-(COD) by the appearance of two condensed rings with 4 fewer carbon atoms. Yet, the olefins are each 4 carbons removed from the other as in the case of 1,5-(COD).

An analysis of the 360 MHz ('1)H NMR spectra of the title compounds in ('2)H(,2O) is presented. The ('3)J values for the ribose vicinal protons of S-adenosyl-L-methionine are consistent with a predominantly C(,3')-exo conformation and with one highly favored gauche-anti conformation about the C(,4')-C(,5') bond. The corresponding ('3)J values for S-adenosyl-L-homocysteine imply a similar C(,3')-exo ribose ring conformation, but the orientation about the C(,4')-C(,5') bond is distributed between two gauche-anti rotamers. The methionine side chain of S-adenosyl-L-methionine has approximately equal populations of rotational isomers about the C(,(alpha))-C(,(beta)) and C(,(beta))-C(,(gamma)) bonds, whereas the side chain of S-adenosyl-L-homocysteine exhibits a conformational preference for the gauche-anti conformations about the C(,(alpha))-C(,(beta)) bond. ('1)H and ('13)C NMR spectra of commercially available samples of (-)S-adenosyl-L-methionine consistently available samples of (-)S-adenosyl-L-methionine consistently reveal the presence of a small amount of the (+) sulfonium diastereomer. This assignment was confirmed by the synthesis of both the ('1)H and ('13)C methyl derivatives of S-adenosyl-L-homocysteine. Arguments are presented to explain the failure of previous workers to detect (+)S-adenosyl-L-methionine in biological preparations. The possible biological significance of this finding is discussed with reference to the enzyme S-adenosyl-L-methionine: L-homocysteine S-methyltransferase which employs both (-)S-adenosyl-L-methionine and (+)S-adenosyl-L-methionine as methyl donors. An improved purification of S-Adenosyl-L-methionine: L-homocysteine S-methyltransferse (EC. 2.1.1.10) from Saccharomyces cerevisiae is reported. The enzyme was purified approximately 1500-fold by toluene extraction, ammonium sulfate precipitation, Sephadex G25 gel exclusion chromatography, DEAE Sephadex ion-exchange chromatography and affinity chromatography on L-methionine AH-Sepharose 4B. The procedure affords a 12-fold increase in yield and a 3-fold increase in purification over the previous fractionation scheme. It is hoped that the availability of a highly purified preparation of the enzyme will provide the basis for an investigation of enzymatic transmethylation in which the fate of the sulfonium diastereomers of S-adenosyl-L-methionine is directly observable by NMR spectroscopy.

A series of monosubstituted tungsten(0)pentacarbonyl complexes, W(CO)5L (L = water, hydrogen sulfide, pyrazine, pyrimidine, 4,4'-bipyridine, 4-cyanopyridine, isonicotinamide, and methanol) were synthesized and characterized. The purpose of this project was to determine the effect of the W(CO)5 moiety on the coordinated ligand, L. The visible spectra of the synthesized W(CO)5L complexes typically exhibited a maximum around 400 nm ((epsilon) (TURN) 4000). The infrared spectra of these complexes exhibited the characteristic three band pattern (2A1 + E) in the carbonyl region ((TURN)2070 cm-1, (TURN)1930 cm-1, (TURN)1900 cm-1. The pKa's of the ligands coordinated to the W(CO)5 moiety were determined. When the ligand was basic, the pKa of the ligand's conjugate acid was determined. The pKa's of water changed from 15.8 to 4.8 upon coordination. The rest of the ligand pKa's changed in a similar fashion upon coordination; from 0.6 to -0.4 for coordinated pyrazine; from 1.3 to -0.4 for coordinated pyrimidine; from 1.9 to -0.3 for coordinated 4-cyanopyridine; and from 4.8 to -0.7 for coordinated 4,4'-bipyridine. The effect of the W(CO)5 moiety on coordinated ligands is to make the ligands more acidic. This result is explained by the presence of strong (pi)-back bonding between tungsten and the carbonyls. The methanoltungsten(0)pentacarbonyl complex was very labile at room temperature in the presence of acetonitrile. The substitution reaction followed the rate law -d{complex}/dt = k(,1){complex} + k(,2){CH(,3)CN}{complex}. At 24.6(DEGREES)C, k(,1) = 1.4 x 10('-3) sec('-1) and k(,2) = 3.6 x 10('-2) M('-1)sec('-1). The activation parameters were calculated: (DELTA)H(,1)('(DAG)) = 9 kcal/mole; (DELTA)S(,1)('(DAG)) = -42 eu; (DELTA)H(,2)('(DAG)) = 9 kcal/mole; and (DELTA)S(,2)('(DAG)) = -34 eu. Since the substitution of methanol occurs so readily at room temperature, W(CO)5 (methanol) should be very useful as a synthetic intermediate. The use of this complex would avoid the problems involved in direct synthesis of W(CO)5L complexes such as disubstituted products or bridged binuclear complexes.

The purpose of this study was to prenare and characterize the palladium (II) and platinum (II) chelates of 1-pyrrolidineacetic acid, 1-piperidineacetic acid, and hexahydro-1-azepineacetic acid. The ligands were prepared by reacting the cyclic secondary arnines (pyrrolidine, piperidine, and hexahydroazepine) with sodium chloroacetate. The resulting cyclic tertiary amino acids were saponified and, finally, converted to the hydrochloride salts by neutralization with hydrochloric acid. The chelates were prepared by adding 1.0 millimole of K2PdC14 or K2PtC14 to a solution made by dissolving 2.0 Millimoles of amino acid hydrochloride in 25 ml. of water. The pH was adjusted to 7.4 and the solution was steam heated for an hour. That volume was reduced to 25 ml. by evaporation. Crystals began to form in one to three days and crystallization was complete in seven days. The products were not recrystallized since no appropriate solvents could be found. The six coordination compounds prepared are unreported in the literature. Elemental analyses, UV-visible spectra, and IR spectra were utilized to elucidate the structure of the coordination compounds. 'l'he amino acids form chelates between the carboxyl and amine groups with the form: M(amino acid)2 . The three amino acids are believed to form square planar complexes with palladium and platinum. It is proposed that the six new compounds are: cis bis 1-pyrrolidineacetato palladium (II), cis bis 1-pyrrolidineacetato platinum (II), cis bis 1-piperidineacetato palladium (II) , cis bis 1-pioeridineacetato platinum (II), trans bis hexahydro-1-azepineacetato palladium (II) , trans bis hexahydro-1-azepineacetato platinum (II). The ionization constants of the three amino acids were determined using the poteniometric method of Albert and Sergeant. The ionization constants of 1-pyrrolidineacetic acid and hexahydro-1-azepineacetic acid are unreported in the literature. The stability constants of all six of the coordination compounds were determined using the method of Albert and Serqeant. This method involved the potentimletric titration of a solution 0.005 molar in K2PdCl4 or K2PtCl4 and 0.01 molar in amino acid hydrochloride with o.1N ootassium hydroxide at 25°C. The stability constants of the chelates differ only slightly with the ring structure of the amino acids under investigation. The stability constants of the palladium chelates are about 102 greater than the corresponding platinum chelates

<p>The moduli space of Abelian differentials on Riemann surfaces admits a natural action by $\mathrm{SL}\left(2,\mathbb{R}\right)$.  This thesis is concerned with using the classification of invariant measures for this action due to Eskin and Mirzakhani, to study the growth of closed geodesics in the support of an invariant measure coming from the closure of an orbit for the $\mathrm{SL}\left(2,\mathbb{R}\right)$-action. These are always subvarieties of moduli space. For $0 \leq \theta \leq 1$, we obtain an exponential bound on the number of closed geodesics in the orbit closure, of length at most $R$, that have at least $\theta$-fraction of their length in a region with short saddle connections.</p>