Nuclear magnetic resonance, crystal, and molecular structure analysis of 5,10-dihydro-10-methyl-5-phenylacridophosphin-10-ol and related "butterfly" C-P heterocycles. Evidence of a P...H-O hydrogen bond in the crystal of the title compound

Phosphorus‐Containing Dibenzonaphthanthrenes: Electronic Fine Tuning of Polycyclic Aromatic Hydrocarbons through Organophosphorus Chemistry

“…This process is most likely analogous to the wing‐flip motion of the butterfly‐shaped phosphaanthracenyl fragment, as already described for related acridophosphines (Figure ) . From the variable‐temperature (VT) 31 P NMR line‐shape analysis (see the Supporting Information), a Gibbs free activation energy Δ G ≠ of 15.6 kcal mol −1 was obtained for the proposed wing‐flip in 10 , with Δ H ≠ =16.1 kcal mol −1 and Δ S ≠ =1.8 cal mol −1 K −1 .…”

“…This process is most likely analogous to the wing-flip motion of the butterfly-shaped phosphaanthracenyl fragment, as already described for relateda cridophosphines (Figure 2). [11,17] From the variable-temperature (VT) 31 PNMR line-shape analysis (see the Supporting Information), aG ibbs free activation energy DG ¼ 6 of 15.6 kcal mol À1 was obtained for the proposed wing-flip in 10,with DH ¼ 6 = 16.1 kcal mol À1 and DS ¼ 6 = 1.8 cal mol À1 K À1 .C onsidering the increased stericd emand of the phenylm oieties, the value of DG ¼ 6 is slightly highera st hat re-ported previously for the dicyanovinylidene-bridged system with DG ¼ 6 = 14.3 kcal mol À1 . [11] Single crystals of compounds 3-5 and 7 suitable for X-ray crystallographic analysisw ere obtained by slow evaporation of the compound solutionsi nC H 2 Cl 2 /n-hexane mixture (Figure 3).…”

Organic Electron Acceptors Comprising a Dicyanomethylene‐Bridged Acridophosphine Scaffold: The Impact of the Heteroatom

“…In the 1 H NMR spectrum of amine S1 at room temperature, sharp signals are observed. In contrast, phosphine 2 shows broadened signals under the same conditions indicating a “wing‐flip“ motion of the butterfly‐shaped heteroanthracenyl fragment between conformer A and B, as already hypothesized for related acridophosphine systems (Figure ) . From the variable‐temperature (VT) 31 P NMR line‐shape analysis, a Gibbs free activation energy Δ G ≠ of 14.3 kcal mol −1 was obtained for this process involving 2 , with Δ H ≠ =13.6 kcal mol −1 and Δ S ≠ =−2.2 cal K −1 mol −1 .…”

“…In contrast, phosphine 2 shows broadened signals under the same conditions indicatinga"wing-flip" motion of the butterfly-shaped heteroanthracenyl fragment between conformer A and B, as already hypothesized for related acridophosphine systems( Figure1). [15] From the variable-temperature (VT) 31 PNMR line-shapea nalysis, aG ibbs free activation energy DG°of 14.3 kcal mol À1 was obtained for this process involving 2,w ith DH°= 13.6 kcal mol À1 and DS°= À2.2 cal K À1 mol À1 .T he DG°value is considerably higher than that reported for related dicyanomethylene-bridged nitrogen-containing systems, with ac alculated value of about 6.0 kcal mol À1 . [8b] Similare xperiments suggestt he coalescence temperature for the oxidized organophosphorus compounds 3-5 to be somewhat lower than for 2 (for details, see the Supporting Information).…”

The crystal and molecular structure of 10-methyl-5-phenyldibenzo[b,e]phosphorinan-10-ol 5-oxide (5,10-dihydro-10-methyl-5-phenylacridophosphin-10-ol 5-oxide)

“…The compound was synthesized by addition of H20 2 to 5,10-dihydro-10-methyl-5-phenylacridophosphin-10-ol (II), for which the solidstate structure has been reported (Chen, Ealick, van der Helm, Barycki & Berlin, 1977). The structure of a third related compound, 5,10-dihydro-10-hydroxy-5,10-dimethyl-5-phenylacridophosphonium iodide (III), which was prepared by addition of methyl iodide to (II), has also been reported (Wu, Nunnery, van der Helm & Berlin, 1977).…”