Reactive organometallics from organotellurides: application in organic synthesis

Abstract

Neste artigo é revisada a preparação de organometálicos reativos a partir de teluretos orgânicos. É comentado o uso dos organometálicos preparados dessa maneira na síntese de substâncias bioativas.In this paper the preparation of reactive organometallics starting from organotellurides is reviewed. The application of the reactive organometallics prepared in this way in the synthesis of bioactive compounds is commented.

Reactions of N‐alkenyl Thioureas with p‐alkoxyphenyltellurium Trichlorides

“…Computational study. In the computational study, we were focused on the investigation of the possible reaction mechanism between 4-methoxyphenyltellurium trichloride and N-alkenyl substituted thioureas: N-allylthiourea (1), N-methallylthiourea (2), N-allyl-N 0 -phenylthiourea (4), N-allyl-N 0 -methylthiourea (15). Despite the fact that N-allyl-N 0 -methylthiourea (15) was not investigated experimentally, it is a convenient object for theoretical investigation of the electronic influence of substituents, so it was included in the studied raw of thioureas.…”

“…Reportedly, aryltellurium trihalides are quite promising electrophilic reagents [1][2][3][4][5]; however, the reactions of aryltellurium trihalides with acyclic unsaturated thioureas have not yet been investigated. Reactions of N-alkenyl thioureas with electrophilic reagents can lead to the formation of addition products or heterocyclic systems.…”

Synthesis of Organochalcogen Compounds using Non-Conventional Reaction Media

“…Diorganyl chalcogenides or chalcogen ethers also are versatile tools in organic chemistry due to their applicability in asymmetric catalysis, the usefulness in the preparation of reactive organometallics, which are used in the synthesis of bioactive compounds . The organochalcogen moiety can be introduced as either nucleophiles or electrophiles in other organic molecules, producing valuable intermediates for organic synthesis…”

Determination of Tellurium in Tellurium-Containing Organic Compounds by Microwave Plasma-Atomic Emission Spectrometry

“…The increased interest in this field is due to widely use of these substances as catalysts in organic reactions (e.g., rubber vulcanization), inhibitors of metal corrosion, insecticides, fungicides, components of special photographic materials, pharmaceuticals etc [1][2][3][4][5]. In view of great practical importance of these compounds for science and technology, a large number of analytical methods for the determination of tellurium in various objects were developed: gravimetric methods based on the precipitation of elemental tellurium by treating with inorganic and organic reducing agents, [6][7][8]; titrimetric methods based on redox reactions using iodide-anion, salts of iron(II), chromium(II) or titanium(III) as reducing agents, as well as potassium permanganate or dichromate as oxidizing agents for Te (IV), [9][10][11]; electrochemical methods, which allow one to determine the tellurium and selenium at simultaneous presence with a sensitivity being 10 -5 M, [12][13][14]; spectrophotometric methods based on the formation of complexes with sulfur-containing organic reagents (diethyldithiocarbamate, thiurea, and their derivatives, bismuthiol II, and so on [15,16] or on the formation of ion pairs of tellurium acido complexes with organic bases-pyrazolone derivatives and rhodamine dyes [17][18][19].…”