3425-46-5Relevant articles and documents
Regio- And stereoselective synthesis of new ensembles of diversely functionalized 1,3-thiaselenol-2-ylmethyl selenides by a double rearrangement reaction
Albanov, Alexander I.,Amosova, Svetlana V.,Filippov, Andrey A.,Makhaeva, Nataliya A.,Potapov, Vladimir A.
, p. 515 - 523 (2020)
The reaction of 2-(bromomethyl)-1,3-thiaselenole with potassium selenocyanate proceeded via a rearrangement with ring expansion, leading to a six-membered 2,3-dihydro-1,4-thiaselenin-2-yl selenocyanate (kinetic product) which in turn underwent rearrangement with ring contraction to a 1,3-thiaselenol-2-ylmethyl selenocyanate (thermodynamic product). These rearrangements occurred by a nucleophilic attack of the selenocyanate anion at two different carbon atoms of the seleniranium intermediate. The efficient regioselective synthesis of alkyl, allyl, 2-propynyl, benzyl, 4-fluorobenzyl, and 2-pyridinylmethyl 1,3-thiaselenol-2-ylmethyl selenides was developed based on the generation of sodium 1,3-thiaselenol-2-ylmethylselenolate from 1,3-thiaselenol-2-ylmethyl selenocyanate or bis(1,3-thiaselenol-2-ylmethyl) diselenide followed by nucleophilic substitution reactions. Sodium 1,3-thiaselenol-2-ylmethylselenolate underwent nucleophilic addition to alkyl propiolates in a regio- and stereoselective manner affording 1,3-thiaselenol-2-ylmethyl vinyl selenides in high yields predominantly with Z-configuration. Not a single representative of the 1,3-thiaselenol-2-ylmethyl selenide scaffold has been previously described in the literature.
A Comprehensive Study on the Full Series of Alkali-Metal Selenocyanates AI[SeCN] (AI=Li?Cs)
Shlyaykher, Alena,Ehmann, Marvin,Karttunen, Antti J.,Tambornino, Frank
, p. 13552 - 13557 (2021)
The full series of quasibinary alkali-metal selenocyanates was synthesized either by oxidation of the respective cyanides (A=Li?Rb) or by metathesis (A=Cs). For Li[SeCN] only ball-milling and subsequent annealing led to the isolation of the quasibinary selenocyanate. Their structures were refined from single-crystal and powder X-ray data. The respective solid-state IR and Raman spectra were interpreted with the aid of solid-state quantum-mechanical calculations and DSC-TGA measurements allowed for extraction of melting points. Only for Li[SeCN] a possible phase transition was observed that is discussed on the basis of VT-PXRD experiments. It is also the only quasibinary selenocyanate to form a hydrate (Li[SeCN] ? 2H2O).
A Scalable Process for the Synthesis of 1,2-Dialkyldiselanes and 1-Alkaneselenols
Cooksey, John P.,Kocieński, Philip J.,Blacker, A. John
supporting information, p. 2571 - 2575 (2019/11/14)
A four-step telescoped process for the synthesis of 1-alkaneselenols entails (1) the rapid formation of potassium selenocyanate from potassium cyanide and selenium in methanol, (2) the nucleophilic substitution of bromoalkanes or alkyl tosylates with potassium selenocyanate, (3) the mild base-catalyzed conversion of the resultant 1-alkaneselenocyanates to 1,2-dialkyldiselanes (the Krief reaction), and (4) the reduction of the resultant 1,2-dialkyldiselanes with hypophosphorous acid to give the desired 1-alkaneselenols. The process has been used to produce 1-octaneselenol on a 10.4 mol scale. Nine examples of the process are described.