ChemInform Abstract: NUCLEOPHILIC ADDITION OF TELLUROPHENOLATE ANION TO α‐ACETYLENE KETONES

Abstract

Alkyl‐ und arylsubstituierte Äthinylketone (I) addieren p‐Methoxytellurophenolat‐natrium (II) unter Bildung der β‐Ketovinylaryltelluride (III).

Hydrozirconation of Lithium Alkynylselenolate Anions. Generation and Reactions of α-Zirconated Vinyl Selenide Intermediates

“…Over the past decades, numerous groups have investigated various aspects of organotellurium compounds, especially their preparation and use in organic synthesis. , This has been particularly true for tellurium-containing unsaturated systems. ,− Among various synthetic strategies, the tellurium/metal exchange reactions in vinylic tellurides, as represented by Te/Li, Te/Cu, Te/Zn, Te/Mg, Te/Ca, and Te/Na 7 transmetalations, possess a number of ideal properties. These reactions may take place with regio- and stereospecificity.…”

“…In combination with the hydrotelluration of alkynes 1,4c,e,g,i,8 or with the hydrozirconation 3c (or hydroalumination 3b ) of acetylenic tellurides, these reactions permit the exclusive preparation of ( Z )-vinylmetallic reagents that are often difficult to obtain by other methods . Because of such merits, intensive efforts have been focused on creating new methods for the synthesis and synthetic transformations of vinylic tellurides, ,− tellurobutenynes, 3d,4e,g,j,k and tellurobutadienes. 3b,4c,i,k,l, …”

β-Telluroacroleins and tellurovinyl ketones: synthesis, reactions and structures

“…A large variety of telluroacroleins and tellurovinyl ketones non-substituted in the a-position were prepared by nucleophilic addition of alkane(arene)tellurolate anions generated by reduction of dialkyl(aryl) ditellurides with sodium borohydride in methanol or ethanol to the triple bonds of acetylenic aldehydes or ketones 13 (Table 4). 1,14,15,25,26 The reaction proceeds under a The assignment was made on the basis of the identity of the compounds synthesised to those prepared from b-chloroacroleins. b The assignment was made on the basis of coupling constants of olefinic protons in the 1 H NMR spectra.…”

“…The first b-telluroacroleins and b-aryltellurovinyl ketones were prepared by nucleophilic addition of arenetellurolate anions ArTe 7 to a-acetylenic aldehydes and ketones (yields 65% ± 75%). 1 Bis(b-acylvinyl) tellurides were synthesised in 3% ± 11% yields 2 using a similar approach, i.e., by nucleophilic addition of the telluride anion Te 27 to a-acetylenic ketones (the reasons for the low yields of ketone will be discussed below). Two other types of b-tellurovinylcarbonyl compounds, viz., aryl b-chlorotellurovinyl ketones and aryl b-trihalogenotellurovinyl ketones were prepared in the 1980's.…”

Unexpected Reaction of 1-Butyltelluro-4-phenyl-1-buten-3-yne under Rupe Reaction Conditions

“…However, limited reports on the synthesis of highly functionalized vinylic tellurides have appeared in the literature . Synthesis of ( Z )-β-(phenyltelluro)acrylate, ( Z )-β-(aryltelluro)acrylic acid derivatives, ( Z )-β-(aryltelluro)-α,β-unsaturated ketones, − and β-(organyltelluro)acroleins by the hydrotelluration of appropriate acetylenic derivatives were described. The synthetic potential of these β-telluro-α,β-unsaturated carbonyl compounds has been demonstrated, since ethyl ( Z )-β-(phenyltelluro)acrylate reacts with Grignard reagents catalyzed by nickel(II) or cobalt(II) phosphine complex to form carbon−carbon bonds 2 and the β-(organyltelluro)acroleins are transformed into the corresponding (organyltelluro)butadienes in good yields via a Wittig reaction .…”