Science.gov (United States)

The objectives of this project are to develop feasible synthetic routes to produce (1) 4(4`-hydroxy-5`,6`,7`,8`-tetrahydro-l`-naphthylmethyl )- 6-methyldibenzothiophene, and (2) a 1-hydroxynaphthalene-benzothiophene polymer. Our experimental work during this quarter concentrated on. As several possible synthetic routes to the target molecule, 4(4`-hydroxy-5`,6`,7`,8`-tetrahydro- l`-naphthylmethyl )-6-methyldibenzothiophene. We tried synthesizing the intermediates for our first method, in which we couple a metalated 4-methyldibenzothiophene with 4-formyl-5,6,7,8-tetrahydro-1-naphthol. We found that we could easily metalate dibenzothiophene, and then add a methyl group to the 4-position to give 4-methyldibenzothiophene in greater than 80% yield by using t-butyllithium in tetrahydropyran followed by dimethylsulfate. However, adding the second metal to the desired 4` position using the same method was more difficult, and instead the reaction occurred on the methyl ...

Science.gov (United States)

Most of the general population is exposed to carbaryl and other contemporary-use insecticides at low levels. Studies of laboratory animals, in addition to limited human data, show an association between carbaryl exposure and decreased semen quality. In the present study we explored whether environmental exposures to 1-naphthol (1N), a metabolite of carbaryl and naphthalene, and 3,5,6-trichloro-2-pyridinol (TCPY), a metabolite of chlorpyrifos and chlorpyrifos-methyl, are associated with decreased semen quality in humans. Subjects (n=272) were recruited through a Massachusetts infertility clinic. Individual exposures were measured as spot urinary concentrations of 1N and TCPY adjusted using specific gravity. Semen quality was assessed as sperm concentration, percent motile sperm, and percent sperm with normal morphology, along with sperm motion parameters (straight-line velocity, curvilinear velocity, and linearity). Median TCPY and 1N concentrations were 3.22 and ...

Energy Technology Data Exchange (ETDEWEB)

Coal liquefaction investigations required the availability of model compounds for mechanistic investigations. Towards this end, IITRI was funded to develop an approach for the synthesis of one of the target compound. This study was carried out in several phases as outlined here. Initial synthetic investigations on obtaining 2-tetrolol was carried out using high pressure and temperature reduction with Raney nickel catalyst. The next step consisted in incorporation of a hydroxymethyelene group at the C-3 position. This was successfully carried out utilizing 2-tetrolol, formaldehyde, and calcium oxide. An alternate improved method was developed using 3-carboxyl-2-naphthol. This required less time, gave a cheer product in higher yield. Efforts at the introduction of a chloromethylene group only yielded polymeric material or starting material in spite of protection the phenolic group by various groups. They synthesis of 3, 5-dimethyl-6- bromobenzyl chloride was ...

Energy Technology Data Exchange (ETDEWEB)

Organic materials released from energy-related activities could affect human health and the environment. To better assess possible impacts, we developed a model to predict the fate of spills or discharges of pollutants into flowing or static bodies of fresh water. A computer code, Aquatic Pathways Model (APM), was written to implement the model. The computer programs use compartmental analysis to simulate aquatic ecosystems. The APM estimates the concentrations of chemicals in fish tissue, water and sediment, and is therefore useful for assessing exposure to humans through aquatic pathways. The APM will consider any aquatic pathway for which the user has transport data. Additionally, APM will estimate transport rates from physical and chemical properties of chemicals between several key compartments. The major pathways considered are biodegradation, fish and sediment uptake, photolysis, and evaporation. The model has been implemented with parameters for distribution of phenols, an ...