2- Thienyl tellurolates

Sodium hydrogen telluride, sodium 0,0-diethyl phosphorotellurolate, alkali 2-thienyl tellurolates and bis(triphenylstannyl) telluride °/KF reduce a-haloketones to the corresponding ketones. 

Thienyl tellurolates also remove several different substituents such as acetoxy, mesyloxy, phenylthio and 2-thienyltelluro groups, as well as effect the reductive dehalo-genation of bromoacetanilide, and of a-haloacids (such as a-bromophenylacetic acid, a-bromo-l-naphthylacetic acid and a-chlorodiphenylacetic acid). ... 

Amines are regenerated from the protecting derivatives trichloro-f-butylcarbamates by treatment with sodium 2-thienyl tellurolate. The reagent is generated in a catalytic cycle by reduction of the corresponding diteUuride with sodium borohydride. 

Method G. ° A catalytic cycle is also involved in this method. Sodium thienyl tellurolate, generated from the ditelluride and NaBH4, attacks a bromine atom and the formed tel-lurenyl bromide reacts with another tellurolate molecule regenerating the starting ditelluride. 

Figure 13 The discrete tellurolate anions in (a) (Ph4P)(TeTh) (Th = 2-thienyl, C4H3S) and (b) [K(18-crown-6)][Te 2,4,6-(Me2CH)3 C6H2 ] ...

Organometallic Derivatives of Monocyclic Thiophens - Lithium. Numerous a-substituted thiophens have been prepared via metallation of thiophens with organolithium derivatives. Thus 2-thienyl-lithium has been allowed to react with tetraisopropylthiuram disulphide to give 5-(2-thienyl) A(,A -di-isopropyl-dithiocarbamate in quantitative yield. ° Through the reaction of 2-thienyl-lithium with tellurium in THF, the tellurolate was obtained, which was converted into various products. The reaction of 2-thienyl-lithium with 1,1-dichloro-2,2-difluoroethene has been developed into a very useful method for... 

---