Reaction of N,N-Dimethyltryptamine with Dichloromethane Under Common Experimental Conditions.

A large number of clinically used drugs and experimental pharmaceuticals possess the N,N-dimethyltryptamine (DMT) structural core. Previous reports have described the reaction of this motif with dichloromethane (DCM), a common laboratory solvent used during extraction and purification, leading to the formation of an undesired quaternary ammonium salt byproduct. However, the kinetics of this reaction under various conditions have not been thoroughly described. Here, we report a series of experiments designed to simulate the exposure of DMT to DCM that would take place during extraction from plant material, biphasic aqueous work-up, or column chromatography purification. We find that the quaternary ammonium salt byproduct forms at an exceedingly slow rate, only accumulates to a significant extent upon prolonged exposure of DMT to DCM, and is readily extracted into water. Our results suggest that DMT can be exposed to DCM under conditions where contact times are limited (<30 min) with minimal risk of degradation and that this byproduct is not observed following aqueous extraction. However, alternative solvents should be considered when the experimental conditions require longer contact times. Our work has important implications for preparing a wide-range of pharmaceuticals bearing the DMT structural motif in high yields and purities

Synthesis of Early Transition Metal Bisphenolate Complexes and Their Use as Olefin Polymerization Catalysts

Bisphenolate ligands with pyridine- and benzene-diyl linkers have been synthesized and metalated with group 4 and 5 transition metals. The solid-state structures of some of the group 4 complexes have been solved. The titanium, zirconium, hafnium, and vanadium complexes were tested for propylene polymerization and ethylene/1-octene copolymerization activities with methylaluminoxane as cocatalyst. The vanadium(III) precatalyst is the most active for propylene polymerization and shows the highest 1-octene incorporation for ethylene/1-octene copolymerization. The zirconium(IV) precatalyst was the most active for propylene polymerization of the group 4 precatalysts. Titanium(IV) and zirconium(IV) precatalysts with pyridine-diyl linkers provided mixtures of isotactic and atactic polypropylene while titanium(IV) precatalysts with benzene-diyl linkers gave atactic polypropylene only. The hafnium(IV) precatalyst with a pyridine-diyl linker generated moderately isotactic polypropylene

The chemistry of Pseudocyphellaria impressa S. Lat. in New Zealand

As part of a detailed study of the nomenclature and taxonomy of the New Zealand species of Pseudocyphellaria it has been noted that the chemistry of the P. impressa (Hook & Taylor) Vainio aggregate, that is species with a markedly faveolate (honeycomb- like) upper surface and a green algal phycobiont, is particularly complex. The 45 lichen substances detected fall into four distinct groupings, here designated as 'Codings'. The aim of this contribution is to investigate suitable methods for revealing this chemical assemblage by t.l.c. and, as far as is currently possible, to identify the range of substances. No conscious attempt is made to assign the four chemical Codings to particular taxa or species groupings; the taxonomy of the group will be discussed elsewhere. The four Codings proved to be remarkably uniform and constant considering the range and number of substances involved; such variation that occurred was only in the presence and concentration of accessory substances. Although this work only concerns New Zealand material, similar patterns occur in related taxa of the group present in southern South America, south-east Australia and Tasmania

Mild and facile synthesis of multi-functional RAFT chain transfer agents

In this paper we will describe the synthesis and characterization of a series of novel chain transfer agents for application in reversible addition fragmentation chain transfer polymerization (RAFT). The facile and mild conditions used for the synthesis of these new chain transfer agents should allow for the application of these methods for the preparation of a wide range of multifunctional chain transfer agent species. Some initial polymerization data for these multifunctional chain transfer agents is also reported

Fragment Coupling and the Construction of Quaternary Carbons Using Tertiary Radicals Generated From tert-Alkyl N-Phthalimidoyl Oxalates By Visible-Light Photocatalysis.

The coupling of tertiary carbon radicals with alkene acceptors is an underdeveloped strategy for uniting complex carbon fragments and forming new quaternary carbons. The scope and limitations of a new approach for generating nucleophilic tertiary radicals from tertiary alcohols and utilizing these intermediates in fragment coupling reactions is described. In this method, the tertiary alcohol is first acylated to give the tert-alkyl N-phthalimidoyl oxalate, which in the presence of visible-light, catalytic Ru(bpy)3(PF6)2, and a reductant fragments to form the corresponding tertiary carbon radical. In addition to reductive coupling with alkenes, substitution reactions of tertiary radicals with allylic and vinylic halides is described. A mechanism for the generation of tertiary carbon radicals from tert-alkyl N-phthalimidoyl oxalates is proposed that is based on earlier pioneering investigations of Okada and Barton. Deuterium labeling and competition experiments reveal that the reductive radical coupling of tert-alkyl N-phthalimidoyl oxalates with electron-deficient alkenes is terminated by hydrogen-atom transfer

Organic compounds in hydraulic fracturing fluids and wastewaters: A review

High volume hydraulic fracturing (HVHF) of shale to stimulate the release of natural gas produces a large quantity of wastewater in the form of flowback fluids and produced water. These wastewaters are highly variable in their composition and contain a mixture of fracturing fluid additives, geogenic inorganic and organic substances, and transformation products. The qualitative and quantitative analyses of organic compounds identified in HVHF fluids, flowback fluids, and produced waters are reviewed here to communicate knowledge gaps that exist in the composition of HVHF wastewaters. In general, analyses of organic compounds have focused on those amenable to gas chromatography, focusing on volatile and semi-volatile oil and gas compounds. Studies of more polar and non-volatile organic compounds have been limited by a lack of knowledge of what compounds may be present as well as quantitative methods and standards available for analyzing these complex mixtures. Liquid chromatography paired with high-resolution mass spectrometry has been used to investigate a number of additives and will be a key tool to further research on transformation products that are increasingly solubilized through physical, chemical, and biological processes in situ and during environmental contamination events. Diverse treatments have been tested and applied to HVHF wastewaters but limited information has been published on the quantitative removal of individual organic compounds. This review focuses on recently published information on organic compounds identified in flowback fluids and produced waters from HVHF

Analysis of priority pollutants in industrial waste water

Issued as Technical reports [nos. 1-3], and Final report, Project no. E-20-65

The Synthesis and Pharmacologic Activity of Some Bis-(2-aminoethyl)-benzenes

Introduction: The isolation of epinephrine from the medulla of the suprarenal gland and the discovery of its amazing therapeutic effects have stimulated intensive research on the synthesis of compounds possessing the basic skeleton of 2-aminoethyl-benzene. The investigation in the past forty years have culminated in the preparation of a large number of this type of amine which are pharmacologically classified as sympatho-mimetic or pressor agents because they generally act on the sympathetic nervous system and cause in increase of blood pressure. However, the 2-aminoethylbenzene derivatives most thoroughly studied have been those whose molecules possessed only one aminoethyl side chain per benzene nucleus. It was von Braun who first reported the synthesis of 1,2-bis(2-aminoethyl)-benzene in 1916 and further noted that this substance did not show the usual sympathominetic activity of 2-aminoethylbenzenes. No other investigation on the derivatives of bis-aminoethylbenzenes has been reported until quite recently when Wood and Gibson prepared a series of p-(2-aminoethyl)-hydroquinones. Pharmacologic assay by the Lilly Research Laboratories of Eli Lilly and Company showed that these compounds possessed little activity. Since the compounds in this series were symmetrically constituted, it seemed desirable to prepare several bis-(2-aminoethyl)-benzenes in which the two 2-aminoethyl groups were unsymmetrically placed with respect to each other and with respect to other substituents of the molecule. Accordingly, M. A. Perry instituted a program in this laboratory that covered the synthesis of o- and m-bis-(2-aminoethyl)-benzenes. At approximately the same time, this investigation was started with the purpose of developing procedures that would lead to o-, m- and p-bis-(2-aminoethyl)-benzenes whose molecules possessed substituents, preferably the hydroxy or methyl or both, on the 1- and 2-carbons of the ethylamino side chain. In addition to this objective, this investigation was started with the purpose of developing suitable methods for obtaining the intermediates which were necessary in the synthesis of bis-(2-aminoethyl)-benzenes. From this point of view, chloro-methylation reactions and the Sommelet reaction were to be studied. Finally, the new amines which resulted from these investigations were to be prepared in quantity for submission to the Lilly Research Laboratories for pharmacologic testing

Chemical Modifications of Condensation Polymers, Chloromethylation and Quaternization.

Chloromethyl methyl ether, 6, generated in situ by reaction of dimethoxymethane with acetyl chloride, was employed to chloromethylate condensation polymers containing oxy-1,4-phenylene repeat units, i.e. poly(oxy-2,6-dimethyl-1,4-phenylene), 3, polyarylether sulfone, 4, and acetylated phenoxy resin, 10. To minimize concomitant crosslinking, the optium reaction ratios are 20:1:0.1 for reagent 6 to polymer to SnCl(,4) catalyst. One chloromethyl group per activated aromatic ring could be introduced: the corresponding concentration of active sites were 5.8, 3.5, and 4.6 meq/g for derivatives of 3, 4, and 10, respectively. All of the derivatives were characterized by NMR, DTA, and TGA techniques. A model segment of polyarylether sulfone was synthesized by condensing 4-chlorophenyl phenyl sulfone with the disodium salt of bisphenol-A. Chloromethylation of the model segment yielded a bischloromethyl derivatives, 14. Quaternization of 14 with tertiary amines in DMSO proceeded to completion: no deviation from second order kinetics was observed. The initial quaternization rate of chloromethylated polyether sulfone, 9, with either triethylamine or quinuclidine was nearly identical to that of 14 under comparable conditions, but deceleration of the reaction on the polymer was apparent at approximately 50% conversion. The rate retardation could not be attributed to steric effect, the extent of chloromethylation of 4, or salt effect. In the quaternization of chloromethylated acetylated phenoxy resin, 11, with triethylamine in DMSO, a rate retardation was observed at 60% conversion. Normal second order kinetics was observed for quaternization of poly(vinylbenzyl chloride). These results demonstrate that the flexibility of the polymer backbone plays an important role in polymer reactivity, particularly when there is a significant change in the polarity of the modified polymer. Rigid polymer chains can not undergo the conformational changes necessary to form charged domains. Quaternization of the moderately flexible 11 with either 2-hydroxyethyldimethylamine, 18, or bis(2-hydroxyethyl)methylamine,19, in DMSO proceeded with autoacceleration. Selective solvation of the developing charges by the hydrophilic hydroxylated substituents may contribute to the rate enhancement. However, quaternization with tri(2-hydroxyethyl)amine exhibited rate retardation when approximately 20% of the functional groups had reacted. Reactions of 18 and 19 with 9 also developed a negative deviation from second order kinetics as the reaction proceeded