Die Kristall‐ und Molekülstruktur von \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm P}\limits^ + {\rm CH}_2 {\rm \bar BH}_3 $\end{document}

Abstract

The Crystal and Molecular Structure of \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm P}\limits^ + {\rm CH}_2 {\rm \bar BH}_3 $\end{document} The zwitterionic molecule (CH3)3\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm P}\limits^ + {\rm CH}_2 {\rm \bar BH}_3 $\end{document} crystallizes orthorhombicly, space group Pna21. While the CH3 groups in (CH3)3PCH2 are bent away from the ylidic function, this strain is relieved in the adduct towards tetrahedral angles. The PCH2 bond distance is elongated on BH3‐addition from a double bond value of 164 to a single bond distance of 175.6 pm.

Borabenzene Adducts of Ylidic Lewis Bases. Syntheses and Structures of 3,5-Me2C5H3BCH2PPh3, 3,5-Me2C5H3BCH(SiMe3)PPh3, and C5H5BN(Ph)PPh31

“…The bond C1−B (1.652(3) Å) is remarkably long, presumably because of increased steric repulsion and reduced Lewis basicity of the trimethylsilyl-substituted methylenephosphorane. The simple adduct Me 3 PCH 2 BH 3 (P−CH 2 = 1.756(6) Å and CH 2 −B = 1.655(11) Å) may be of interest for comparison and also shows a rather long C−B bond …”

Isocyanide and Ylidene Complexes of Boron: Synthesis and Crystal Structures of (2-(Trimethylsiloxy)phenyl isocyanide)−Triphenylborane and (1,2-Dihydrobenzoxazol-2-ylidene)−Triphenylborane

“…To establish 2 unequivocally as a monomeric isocyanide adduct of triphenylborane, we carried out an X-ray structure determination. Structure investigations are rare for triorganoborane Lewis base adducts, and only a few molecular structures have been reported for Lewis bases with carbon donor atoms. 8c,, To our knowledge 2 is so far the only crystallographically characterized isocyanide adduct of a triorganoborane Lewis acid.…”

Carbodiphosphorane C(PPh3)2as a Single and Twofold Lewis Base with Boranes: Synthesis, Crystal Structures and Theoretical Studies on [H3B{C(PPh3)2}] and [{(μ‐H)H4B2}{C(PPh3)2}]+

“…Somewhat surprisingly, no complex of type A with a boron-containing Lewis acid BX 3 has been isolated and structurally characterised either. The complex with the parent Lewis acid BH 3 is of particular interest as adducts of BH 3 with carbon-based Lewis bases are rare and crystal structures of carbon donors have only been published for an N-heterocyclic carbene [21] and an ylide, [22] although microwave structures have been reported for H 3 BCO [23] and H 3 BCNMe. [23] The latter species have also been studied by quantum chemical methods.…”