TY - CHAP

T1 - Five-membered Rings with Two Nonadjacent Heteroatoms with at Least One Selenium or Tellurium

AU - Nielsen, Mogens Brøndsted

PY - 2022

Y1 - 2022

N2 - This article covers the literature in the period 2008–18 on five-membered rings with two non-adjacent heteroatoms with at least one selenium or tellurium (not, however, including 1,3-selenazoles). Various 1,3-oxaselenoles, 1,3-ditellurofulvenes, and 1,3-tellurazoles were studied by X-ray crystallography as were triselenathiafulvalene and tetraselenafulvalene derivatives and their corresponding cation salts. The conducting properties of these salts are also covered in the article. The synthesis and reactivity of various 1,3-oxaselenoles is covered as is the different outcomes of treating 2-(bromomethyl)-1,3-thiaselenole with various nucleophiles; an intermediate resulting from an intramolecular nucleophilic attack of selenium on the halomethyl carbon atom seems to be formed in these reactions according to a theoretical study. Elimination reactions of 4-halo-2-(halomethyl)-1,3-diselenolanes/1,3-thiaselenoles (halo = Br or Cl) are covered. Synthesis of pyrrolo-annelated 1,3-diselenole-2-(thi)ones is presented as well as benzo-fused 1,3-tellurazoles. [3 + 2] Cycloaddition reactions between oxiranes and isoselenocyanates in the presence of boron trifluoride provided a large selection of 2-imino-1,3-oxaselenolanes. The synthesis of 1,3-ditellurofulvenes and 2-imino-1,3-tellurazolines from suitable alkyne precursors is also presented. In addition to the interesting conducting properties of tetraselena/triselenathiafulvalene cation salts, the antioxidant properties of (E)-2-benzylidene-4-phenyl-1,3-diselenole deserves special mention.

AB - This article covers the literature in the period 2008–18 on five-membered rings with two non-adjacent heteroatoms with at least one selenium or tellurium (not, however, including 1,3-selenazoles). Various 1,3-oxaselenoles, 1,3-ditellurofulvenes, and 1,3-tellurazoles were studied by X-ray crystallography as were triselenathiafulvalene and tetraselenafulvalene derivatives and their corresponding cation salts. The conducting properties of these salts are also covered in the article. The synthesis and reactivity of various 1,3-oxaselenoles is covered as is the different outcomes of treating 2-(bromomethyl)-1,3-thiaselenole with various nucleophiles; an intermediate resulting from an intramolecular nucleophilic attack of selenium on the halomethyl carbon atom seems to be formed in these reactions according to a theoretical study. Elimination reactions of 4-halo-2-(halomethyl)-1,3-diselenolanes/1,3-thiaselenoles (halo = Br or Cl) are covered. Synthesis of pyrrolo-annelated 1,3-diselenole-2-(thi)ones is presented as well as benzo-fused 1,3-tellurazoles. [3 + 2] Cycloaddition reactions between oxiranes and isoselenocyanates in the presence of boron trifluoride provided a large selection of 2-imino-1,3-oxaselenolanes. The synthesis of 1,3-ditellurofulvenes and 2-imino-1,3-tellurazolines from suitable alkyne precursors is also presented. In addition to the interesting conducting properties of tetraselena/triselenathiafulvalene cation salts, the antioxidant properties of (E)-2-benzylidene-4-phenyl-1,3-diselenole deserves special mention.

U2 - 10.1016/B978-0-12-818655-8.00046-9

DO - 10.1016/B978-0-12-818655-8.00046-9

M3 - Book chapter

VL - 1

SP - 1015

EP - 1033

BT - Comprehensive Heterocyclic Chemistry IV

PB - Elsevier

ER -