A Cationic Phosphapyramidane

Abstract

Pyramidanes C[C R ] constitute a novel class of highly strained and reactive polyhedral clusters that attracted a great deal of attention of both theoreticians and experimentalists. Although well-studied from the theoretical viewpoint, pyramidanes were synthetically inaccessible, and only very recently their very first isolable representatives have been described. In this Communication, we report on the synthesis and structural studies of the cationic pyramidane with the Group 15 element at the apex, namely, phosphapyramidane, an isoelectronic analogue of the neutral pyramidanes of the Group 14 elements.

A Phosphorus Lewis Super Acid: η5-Pentamethylcyclopentadienyl Phosphorus Dication

“…Notably, the Cp* ligand is h 5 -bonded to the central P atom, with C-P bond lengths ranging from 2.063(6) to 2) Å ). 48 The mean P-C-C angle in [(h 5 -Cp*)P] 2+ is 70.0 . The Lewis acidity of the [(h 5 -Cp*)P] 2+ dication is demonstrated by the weak coordination of the phosphorous with the aromatic ring of a toluene molecular.…”

From Borapyramidane to Borole Dianion

“…As the synthetically feasible route for still unprecedented borapyramidanes, one can propose interaction of the boron halides with the readily available cyclobutadiene dianion derivative 1 2– ·[Li­(thf) + ] 2 that has already been proven to be an indispensable source for a variety of clusters containing both main group elements and transition metals . And indeed reaction of 1 2– ·[Li­(thf) + ] 2 with BCl 3 in hexane formed the desired chloroborapyramidane 2 , as the first pyramidane with the second row element at the apex, isolated as pale-yellow crystals in moderate yield of 51% (Scheme ).…”

Synthesis and Reactivity of the Phosphorus Analogues of Cyclopentadienone, Tricyclopentanone, and Housene

“…[3] To date,only one thermally stable,all-carbon housene E (X = CH 2 ,R = tBu, R' = CO 2 tBu) [4,5] has been reported. Incorporation of heteroatoms such as phosphorus into these molecules is appealing owing to their propensity to accommodate small angles and at the same time provide ac oordi-nation site.Sofar,studies on the phosphorus analogues of A-F are scarce, [6] and only Cowleysdiphosphatricyclopentanone G, [7] Nixonst riphospha analogue of housene H, [8] and Sekiguchism onophosphahousene I [9] have been reported.…”