Showing papers by "Edward C. Taylor published in 1973"

Recent Advances in Organothallium Chemistry

Abstract: Publisher Summary This chapter discusses the recent advances in organothallium chemistry and reports a survey of the major trends in the field during the past twenty years, with particular emphasis on the applications of organothallium compounds (R 3 Tl) to organic chemistry. It focuses on thallation and oxythallation and the utility of these processes in organic synthesis. Organothallium compounds in which the bonding is largely covalent have never been isolated. Treatment of thallium halides with organolithium or Grignard reagents results in a direct formation of either organothallium (III) derivatives or organic products that have been presumed to arise through the intermediacy of initially formed, unstable organothallium species. In contrast to other organothallium compounds, cyclopentadienyl thallium is a remarkably stable compound. Only about a dozen R 3 Tl compounds have been reported so far, and there have been no systematic studies of their properties or reactions. These compounds are the most stable of the three classes of organothallium (III) derivatives and have been prepared by a wide variety of classical organometallic procedures. Many exchange reactions of TlX 3 (X = C1, carboxylate) with organo derivatives of boron, mercury, tin, and lead have been shown to result in the formation of R 2 TlX compounds but are of relatively little preparative significance.

Pteridines part 32, 2‐amino‐3‐cyano‐5‐chloromethylpyrazine 1‐oxide and its conversion to 6‐alkenyl‐substituted pteridines

Abstract: Aus Diketen oder Oximinoaceton erhalt man nach bekannten Reaktionen das β-Chlorbrenzaldehyd-oxim (I), das mit Aminomalodinitril-tosylat (II) zum 2-Amino-3-cyan-5-chlormethyl-pyrazin-1-oxid (IIIa) kondensiert wird.