Ylidylphosphanes and -diphosphanes

Silylphosphanes: Developments in Phosphorus Chemistry

“…166,167 3P 4 (SiMe 2 ) 3 379 The cyclic silylalkylidenephosphorane 429 was obtained as demonstrated in ( 134), 168 but undergoes slowly an isomerization yielding the less strained sixmembered ring 430. 169 Mathiason and Miller 170 and Schmidbaur and Tronich 171 reported the phosphanylation to (Me 433) with PX 3 (X ) Cl, Br), 173 the ylidylphosphanes (Ph 3 PdCR-PR 2 ) and -diphosphanes (Ph 3 PdCR-PR-PR 2 ) 174 as well as the bis(ylidyl)phosphanes (Ph 3 PdCR-P(Ph 3 )-CRd PPh 3 ) 175 and bis(ylide)-substituted phosphenium (Ph 3 PdCR-PdCR-PPh 3 X) and phosphonium halides (Ph 3 PdCR-PX-CRdPPh 3 ) 176 were dealt with. The Si-P bond in silylphosphanes is cleaved by chlorinated silanes and carbosilanes.…”

“…The unstable compound 585 decomposes during some hours (174). Also pure 579, which could be obtained by a HPLC separation, decomposes according to (175).…”

Zwitterionic 1-phosphonioalkyl dithiophosphinates

“…In fact, this reaction was used for the first recorded preparation of a dithiophosphinic acid more than a hundred years ago. In the reaction of triphenylphosphoniumbenzylidyl-t-butylphosphine 1 [3] with excess sulfur or selenium, the first step leading to the phosphine sulfide 2 and selenide 3 is complete within a few minutes, while the second step is slow enough to enable us to observe 2 and 3 in the reaction mixture. Their 31 P-NMR spectra, as compared to that of 1, are characterized by a sharp decrease of 2 J PP [4] and an increase of 1 J PH [5].…”