Lewis Base Stabilized Phosphanylborane

Abstract

The abstraction of the Lewis acid from [W(CO)(5)(PH(2)BH(2)NMe(3))] (1) by an excess of P(OMe(3))(3) leads to the quantitative formation of the first Lewis base stabilized monomeric parent compound of phosphanylborane [H(2)PBH(2)NMe(3)] 2. Density functional theory (DFT) calculations have shown a low energetic difference between the crystallographically determined antiperiplanar arrangement of the lone pair and the trimethylamine group relative to the P-B core and the synperiplanar conformation. Subsequent reactions with the main-group Lewis acid BH(3) as well as with an [Fe(CO)(4)] unit as a transition-metal Lewis acid led to the formation of [(BH(3))PH(2)BH(2)NMe(3)] (3), containing a central H(3)B-PH(2)-BH(2) unit, and [Fe(CO)(4)(PH(2)BH(2)NMe(3))] (4), respectively. In oxidation processes with O(2), Me(3)NO, elemental sulfur, and selenium, the boranylphosphine chalcogenides [H(2)P(Q)BH(2)NMe(3)] (Q = S 5 b; Se 5 c) as well as the novel boranyl phosphonic acid [(HO)(2)P(O)BH(2)NMe(3)] (6 a) are formed. All products have been characterized by spectroscopic as well as by single-crystal X-ray structure analysis.

Stepwise Expansion of a Cp* Ring at Pentelidene Complexes and Stereoselective Formation of Triphosphines

“…[17] The P À B bond (2.000(7) ) in 2 a is slightly lengthened, unlike the corresponding bond in 2 b (1.970(13) ), which is in the range of the starting material (1.976(2) ). [18] The new coordinative PÀP and PÀAs bond lengths (2.237(2) and 2.352(3) , respectively) are in the area of lengthened single bonds (c.f. : b-P 4 : 2.199-2.212 ; [19] for P À As, see Ref.…”

Main Group Lewis Acid/Base‐Stabilised Phosphanylboranes

“…Solvents were purified and degassed by standard procedures. The compounds B(C 6 F 5 ) 3 , [13] (C 6 F 5 ) 3 GaOEt 2 , [13] (C 6 F 5 ) 3 BPH 3 , [19] (C 6 F 5 ) 3 BPPhH 2 , [5] PH 2 BH 2 NMe 3 , [7] ClBH 2 -NMe 3 [20] and PPhH 2 [21] were prepared according to the literature procedures. nBuLi (Fluka, 1.6 molar solution in n-hexane) was used as received.…”

“…[6] Recently we were able to synthesise the first phosphanylborane C, which is stabilised only by a Lewis base. [7] The Lewis acid stabilised phosphanylboranes that we synthesised carry transition metal carbonyls as the Lewis acid. [6] In contrast, less is known about main group Lewis acid stabilised group 13/15 compounds.…”

“…[6] In contrast, less is known about main group Lewis acid stabilised group 13/15 compounds. [5,7,8] ence on the reactivity of the phosphanylboranes [Equation (1)]. For example, photolysis of compound D leads to a dimer with elimination of CO and H 2 .…”

Schrittweise Erweiterung eines Cp*‐Rings am Pentelidenkomplex und stereoselektive Bildung von Triphosphanen

“…[17] Die P-B-Bindung (2.000(7) ) in 2 a ist etwas verlängert, die Bindungslänge in 2 b (1.970(13) ) liegt hingegen im Bereich der Ausgangsverbindung (1.976(2) ). [18] Die neuen koordinativen P-Pund P-As-Bindungen liegen mit 2.237(2) bzw. 2.352(3) im Bereich verlängerter Einfachbindungen (vgl.…”