Selenoethers, synthesis

Levason, W., Quirk, J. J., Reid, G., Smith, S. M., Synthesis, spectroscopic and redox properties of ruthenium complexes with selenoether macrocycles crystal structures of cis-[RuCl2([16]aneSe4)] and trans-[RuCl(PPh3)([16]aneSe4)]PF6 ([16]aneSe4 = 1,5,9,13-tetraselenacyclohexadecane). J. Chem. Soc., Dalton Trans. 1997, 3719-3724. 

Synthesis and multinuclear NMR fH, 77Se, 125Te, 63Cu, 109Ag) spectrometry of Ag1 complexes with o-phenylene-backboned bis(thioethers), bis(selenoethers) and related crystal structure determinations. 

Selective Dealkylations of Aryl Alkyl Ethers, Thioethers and Selenoethers Tiecco. M. Synthesis. 1988, 749. 

Kurth and co-workers prepared libraries of polyisoxazolines 39,40 by solid-phase combinatorial synthesis utilizing polymer-bound olefin 34, nitro-selenoethers 13c and nitroalkanes 13d,e (Scheme 11) [103]. An iterative application of nitrile oxide 1,3-dipolar cycloaddition followed by selenide oxida-tion/elimination steps was employed to afford polymer boimd tri-isoxazolines which could be liberated from the resin via trans-esterification to afford 39,40. 

Heteracalixarenes are important molecular architectures in supramo-lecular chemistry. In the year 2014, an efficient approach for the synthesis of functionalized selenoethers and selenacalix[4]thiophenes, [2,5-(ji-Se) (3,4-dialkoxythiophene) (14TL5232). The selenoethers were prepared by the reaction of various phenols with SeCl2 (shown below) and the latter were synthesized by conventional electrophilic aromatic substitution reactions of dialkoxythiophene and SeCl2. 

Thioethers and selenoethers can be displaced with various nucleophiles after methylation by MeOTf. This has been used extensively in the carbohydrate synthesis field (see the section on glycosylation). A phenylselenide moiety was substituted stere-ospecifically by an alkyl stannane following MeOTf activation in the construction of a C—C bond between two quaternary carbon centers (eq 20). ... 

A novel synthesis of isoselenazoles (150), using bromoseleno-intermediates in the final cyclization stage, comprises the successive treatment, at -80 C, of selenoethers of type (148), e.g. cis-/3-methylseleno-2-propenal, with bromine and ammonia it generally affords the desired heterocycles in very good yield. The precursors (148) are ultimately derived from the appropriate ketones (146), which are first converted into the chloro-aldehydes (147) by the Vilsmeier-Haack reaction, and then treated with methaneselenol in pyridine-triethylamine. They arise as mixtures of cis- and trans-isomers, separable by spinning-band fractional distillation. The u.v. and n.m.r. spectra of the isoselenazoles were recorded and discussed. ... 

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