No abstract

In recent decades, scientists have attempted to make more environmentally friendly chemical synthesis procedures. One area of environmental concern is the amount of electricity required to complete an experiment. An effective means for minimizing the amount of electricity needed to drive chemical reactions to completion is proposed through the use of solar parabolic reflectors. The proposed solar reflectors are assembled by covering unused satellite dishes with Mylar tape, giving the satellite dish reflective properties when the dish is directed at the sun. The ability to use the solar reflector as the sole heat source for organic synthesis reactions is being considered. Comparative studies will be conducted using electrical supplies to compare the solar reflectors ability to generate heat to drive the chemical reactions to completion. Analysis of the products of the reactions will be analyzed using NMR and GC-MS. Preliminary research has shown that the solar reflector is capable of heating a substance to a temperature over 300 °C, which is more than capable to drive most organic synthesis reactions to completion. The synthesis of isobutyrophenone, which is synthesized through a Friedel–Crafts acylation of benzene, has been attempted using the solar reflector.

Recently proposed solar reflectors developed from satellite dishes have the ability to be incorporated into student laboratory procedures to eliminate electricity use while demonstrating green chemistry techniques at the same time.There have been recent attempts to make chemical synthesis procedures more environmentally friendly. As a result, demand to incorporate more green chemistry techniques into student laboratories has increased. Electricity use is one area of environmental concern because fossil fuels are used for the majority of electrical energy in the United States. An effective means for minimizing the amount of electricity needed to drive chemical reactions to completion is proposed through the use of solar parabolic reflectors. A comparative study is conducted using an electrical and solar heat source on the Diels−Alder cycloaddition reaction of maleic anhydride and anthracene. This reaction is chosen as the test reaction due to its widespread use among many undergraduate chemistry programs. Analysis of the products is performed by NMR spectroscopy.

Tiglyglycine (TG), an intermediate product of the catabolism of isoleucine, is increased in the urine of patients with beta-ketothiolase deficiency or with disorders of propionate metabolism. It is also implicated as a useful diagnostic marker in disorders of the respiratory chain. We present a method for the synthesis of TG and tiglyl[13C, 15N]glycine and the development of a stable isotope dilution mass spectrometric assay for TG. We compare data from controls with that from subjects with beta-ketothiolase deficiency and propionyl-CoA carboxylase deficiency, and with six patients with enzyme-confirmed disorders of the respiratory chain. TG was increased in the urine from all of the patient groups. The increased TG excretion did not persist in one patient with a respiratory chain defect, which suggests that, in some patients, multiple sample analysis may be necessary to identify a respiratory chain defect. This is the first urinary compound to be implicated as a potential marker of disorders of the respiratory chain.