Modulating the reactivity of phosphanylidenephosphoranes towards water with Lewis acids

Abstract

Phosphanylidenephosphoranes of the type R−P(PR’3), also known as phospha-Wittig reagents, can be utilized in a variety of bond activation reactions exploiting their phosphinidenoid reactivity. In here, we thoroughly show that...

Photochemical formation and reversible base-induced cleavage of a phosphagallene

“…With H 2 O 1a reacted to give Dip TerPH 2 ( 4 ) quantitatively, 53 clearly underlining the potential of 1a to act as an deoxygenation reagent, while also clearly deviating from the reactivity of Dip TerP(PMe 3 ) towards H 2 O, which afforded the primary phosphine oxide Dip TerP(O)H 2 instead. 54…”

Deoxygenation of chalcogen oxides EO2 (E = S, Se) with phospha-Wittig reagents

“…The mixed phosphorane species B (R = Mes*, E = S) was found to be thermodynamically favoured by 204.6 kJ mol −1 (see chapter 4.3 in the ESI†). 49 RP(S)O can then react with a second equivalent of R-P(PMe 3 ) to give again OPMe 3 and the diphosphene-monosulfide RPP(S)R, in which the R-groups are cis -oriented. Upon heating RPP(S)R is then transformed into the observed thiadiphosphiranes.…”

“…47 These compounds can be classified as "masked" phosphinidenes, showing phosphinidenoid reactivity upon PMe 3 release. We have demonstrated the facile NH- 48 as well as OH-bond 49 activation at the P(I) center as well as the cleavage of the terminal C(sp 2 )-H bonds of N-heterocyclic olefins (NHO) to give P-substituted NHOs. 50 Utilizing phospha-and arsa-Wittig reagents as pnictinidene transfer reagents, phospha-as well as arsaalumenes 51 compounds showing E 13 -E 15 multiple bonding 52 could be generated in the reaction with (Cp*Al) 4 (Scheme 2).…”

“…47 These compounds can be classified as “masked” phosphinidenes, showing phosphinidenoid reactivity upon PMe 3 release. We have demonstrated the facile NH- 48 as well as OH-bond 49 activation at the P( i ) center as well as the cleavage of the terminal C(sp 2 )–H bonds of N-heterocyclic olefins (NHO) to give P-substituted NHOs. 50…”

Reactive FLP–alkyne addition products: a route to anionic and zwitterionic phosphines

“…We recognized that the use of select phosphorus reagents in initial FLP addition reactions could provide a new P-C bond and yet retain the capacity for further reaction. To this end, we noted the innovative work from the groups of Cummins, 22,23 Protasiewicz [24][25][26][27] and Hering-Junghans [28][29][30][31][32][33] that have described the chemistry of phosphinidene precursors. Herein, we first demonstrate that these species do participate in FLPalkyne addition reactions.…”