Studies on the reactivity of group 15 Zintl ions with carbodiimides: synthesis and characterization of a heptaphosphaguanidine dianion

Abstract

Reaction of the hydrogenheptaphosphide dianion, [HP(7)](2-), with one equivalent of bis(2,6-diisopropylphenyl)carbodiimide yielded the exo-functionalized cluster [P(7)C(NDipp)(NHDipp)](2-) (Dipp = 2,6-diisopropylphenyl). This species was characterized by single crystal X-ray diffraction, multielement NMR spectroscopy and electrospray mass-spectrometry. DFT calculations on the dianion were also conducted.

Hydropnictination Reactions of Carbodiimides and Isocyanates with Protonated Heptaphosphide and Heptaarsenide Zintl Ions

“…The neutral hydrogen polyphosphane H 3 P 7 is also available in the presence of a suitably strong acid; however, this species is unstable and readily disproportionates. [26] The nature of the sequestering agent has a pronounced effect on the acidity of the [HP 7 ] 2dianion and the relative stability of the conjugate base [P 7 ] 3-. [5c] Our research group recently reported a bulk synthesis of the hydrogenheptaphosphide dianion, which can be used to access compositionally pure salts of the anion as either [K(2,2,2crypt)] 2 [1]·py (py = pyridine) or [K(18-crown-6)] 2 [1], in high yields (70-80 % from the binary phase K 3 P 7 ).…”

“…[25,26] During the course of these studies we have reported that the hydrogenheptaphosphide dianion [HP 7 ] 2-(1) reacts with carbodiimides to yield exo-functionalized cages with amidine functionalities [-C(NR)(NHR); R = Dipp, iPr, Cy]. [25,26] During the course of these studies we have reported that the hydrogenheptaphosphide dianion [HP 7 ] 2-(1) reacts with carbodiimides to yield exo-functionalized cages with amidine functionalities [-C(NR)(NHR); R = Dipp, iPr, Cy].…”

“…[39] The presence of cations in the crystal lattice was modelled by surrounding the anion with a continuum dielectric by using the COSMO approach. [26] All structures were optimized by using the gradient algorithm of Versluis and Ziegler. Ammonia was selected as a model solvent for consistency with related calculations.…”

Frontiers in the solution-phase chemistry of homoatomic group 15 Zintl clusters

“…In 2012, Goicoechea and co-workers explored the reactivity of [HPn 7 ] 2− (Pn = P, As) with carbodiimides and isocyanates. [62][63][64] It was found that these substrates underwent hydrophosphination across the CvN bond, as pictured in Fig. 8 (37a-40a; 37b-40b).…”

Organo–Zintl Clusters [P7R4]: A New Class of Superalkalis

“…Looking at this difference it is apparently a challenging task if we want to create a superalkali complex out of Zintl ions. Here we address this challenge and show that superalkali complexes can indeed be created from a well-known Zintl ion, P 7 3– …”