Organophosphorus–Tellurium Chemistry: From Fundamentals to Applications

Understanding the Chemical Reactivity of Phosphonium‐Based Ionic Liquids with Tellurium

“…The NMR spectroscopic investigation reveals the formation of the respective trialkylphosphane tellurides as indicated by an upfield shifted resonance at δ ( 31 P)=−12.8 ppm (Figure d) compared to that of pure [P 6 6 6 14 ][N(CN) 2 ] ( δ ( 31 P)=33.4 ppm; Figure a). The large 1 J PTe coupling constant of 1656 Hz is in the range typically observed for phosphane tellurides . The corresponding 125 Te NMR spectrum (Figure c) shows two sets of doublets ( δ ( 125 Te)=−778.3 and −778.7 ppm) revealing the same coupling constant 1 J TeP =1656 Hz, which evidences a P−Te bond formation and the formation of two products, most likely (C 6 H 13 ) 3 PTe and (C 6 H 13 ) 2 (C 14 H 29 )PTe as a consequence of the two different possibilities for alkyl elimination.…”

“…This may contribute, at least partially, to the lower solubility of tellurium in phosphonium based ILs compared to that of selenium. The main reason for the much lower solubility and the markedly different reactivity of tellurium can, however, be attributed to the relatively weak P−Te bond, limiting the formation of the trialkylphosphane tellurides.…”

“…The large 1 J PTe couplingc onstant of 1656Hzi si nt he range typically ob-served for phosphane tellurides. [18] The corresponding 125 Te NMR spectrum ( Figure 5c)s hows two sets of doublets (d( 125 Te) = À778.3 and À778.7 ppm) revealing the same coupling constant 1 J Te P = 1656Hz, which evidences aP ÀTe bond formation and the formation of two products, mostl ikely (C 6 H 13 ) 3 PTea nd (C 6 H 13 ) 2 (C 14 H 29 )PTea saconsequence of the two different possibilities fora lkyl elimination. The observedc hemical shifts and the couplingc onstant values are both within the range of typical organophosphorus(V)-tellurium compounds, [18] indicating the oxidation of the phosphorus(III) species by tellurium.…”

“…However, in the case of tellurium the existence of ac ompetitive IL decomposition route besides the S N 2r eaction must be considered as the formation of the P-organic by-product evidences.T his may contribute, at least partially,t ot he lower solubilityo ft ellurium in phosphonium based ILs compared to that of selenium. The main reason for the much lower solubility and the markedly different reactivityo ft ellurium can, however,b ea ttributed to the relativelyw eak PÀTe bond, [18] limiting the formation of the trialkylphosphane tellurides.…”

Synthesis and Reactivity of Bis(6‐diphenylphosphinoacenaphth‐5‐yl)ditelluride

“…The reaction of 1 with the cyclopentadienyldicarbonyliron dimer [Cp(CO) 2 Fe] 2 gave rise to the formation of the complex (6‐Ph 2 P‐Ace‐5‐)TeFe(CO)Cp ( 3 ), which comprises pseudo‐tetrahedral Fe atoms in a chiral environment. Compounds containing tellurium phosphorus interactions as well as complexes of tellurium with transition metals have received great interest recently and were covered in two comprehensive reviews , …”