Phosphororganische Verbindungen, XXIV. Olefine aus aromatischen Aldehyden mit Diphenylphosphinoxyd‐natrium

Horner, L.; Beck, P.; Toscano, Vicente G.

doi:10.1002/cber.19610940523

Cited by 11 publications

(4 citation statements)

References 12 publications

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“…Diphenylphosphinites of the alkali metals have been well-known for many years, and 31 P NMR studies supported already half a century ago that the metals are bound to the oxygen atom rather than to the phosphorus atom . Several procedures provide suitable access to these phosphinites such as the reaction of neat triphenylphosphane oxide or benzyldiphenylphosphane oxide with LiH and NaH at high temperatures or metalation of diphenylphosphane oxide with butyllithium . Deprotonation of diarylphosphane oxide also succeeded with potassium hydride (KH), yielding tetrameric potassium diarylphosphinites .…”

Section: Introductionmentioning

confidence: 99%

Influence of 18-Crown-6 Ether Coordination on the Catalytic Activity of Potassium and Calcium Diarylphosphinites in Hydrophosphorylation Reactions

et al. 2017

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The addition of 18-crown-6 ether (1,4,7,10,13,16-hexaoxacyclooctadecane) to tetranuclear [(thf)K(OPAryl)] and [(thf)Ca(OPAryl)] yields the corresponding mononuclear complexes [(18C6)K(OPAryl)] [Aryl = Ph (1a), Mes (1b)] and [(18C6)Ca(OPAryl)] [Aryl = Ph (2a), Mes (2b)]. The metathesis reaction of [(thf)K(OPAryl)] with CaI yields the calciate [KCa(thf){OPMes}]. The addition of dimesitylphosphane oxide and crystallization from a hexane solution gives [KCa{OPMes}{MesP(O)H}] (3). The complexes [(thf)K(OPMes)], [(thf)Ca(OPMes)], 1b, 2b, and the calciate 3 are tested as catalysts in the hydrophosphorylation of isopropylisocyanate with dimesitylphosphane oxide, quantitatively yielding N-isopropyl(dimesitylphosphoryl)formamide. The potassium complexes are more efficient catalysts than the calcium congeners, and coordination of 18-crown-6 decelerates the catalytic conversion.

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Section: Introductionmentioning

confidence: 99%

Influence of 18-Crown-6 Ether Coordination on the Catalytic Activity of Potassium and Calcium Diarylphosphinites in Hydrophosphorylation Reactions

et al. 2017

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“…This last result is in keeping with data on copolymers of styrene with (S)-4-methyl-1 -hexene. 7 The CD data in the 205-185-nm region show that the transition of the phenyl ring is optically active and split into a negative and a positive band. This splitting, considering ellipticity and frequency separation of the two bands, has the characteristic exciton form.11 Even if the splitting of the band related to the [B electronic transition of the benzene chromophore might be due to the low-site symmetry,12 it seems at present that exciton interaction is the dominant mechanism.…”

Section: +71mentioning

confidence: 99%

“…based on a phosphorus reagent, requires extreme conditions, and succeeds only with aromatic aldehydes 7. Table I reveals that reagent I is also more effective for…”

mentioning

confidence: 99%

Optically active hydrocarbon polymers with aromatic side chains. III. Circular dichroism between 230 and 185 nm of the aromatic chromophore in high molecular weight hydrocarbons

Ciardelli¹,

Salvadori²,

Carlini³

et al. 1972

J. Am. Chem. Soc.

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HC^r-Com(CN)2(PEt3)2 CH2 7 + OH(5)4. The trapping of 6 by CO results in the regeneration of 1 and thus provides the basis for a catalytic cycle, i.e., 1 3 (5) -6 -1, in which the oxidation of CO by Fe(CN)e3proceeds readily under the catalytic influence of 1, i.e. CO + 2Fe(CN)6=-+ 40H~-U-C032" + 2Fe(CN)e4-+ 2H20 (6) 26600) and the National Institute of Arthritis and Metabolic Diseases (AM 13339) is gratefully acknowledged.13 Hz, CHH'), 3.72 (2 H, d, / = 7 Hz, CHH'), 5.4 (1 H, m, CH). The -allyl region of the nmr spectrum resembles that of other -allyl complexes.9

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“…-Assignments of the Coupling Constants. Since the two four-proton coupling constants of (&)0.046 and ( T )0.020 mT, observed for the radical anion of 2, average in the fast exchange limit to the eight-proton value of (*)0.013 mT, their overall assignment to the aromatic protons at the two benzene rings (4,5,7,8,12,13,15,16-positions) is straight-forward. The by far largest coupling constant of 0.422 mT, which is not affected by exchange, must, therefore, be assigned to the four olefinic protons at the two bridging double bonds of 2' (1,2,9,10-positions).…”

mentioning

confidence: 96%

The Radical Anions of [2.2]Paracyclophane‐1,9‐diene and Some of its Derivatives. An Unexpected Conformational Interconversion

Bruhin

Gerson

Möckel

et al. 1985

Helvetica Chimica Acta

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Dedicated to Prof. Virgil Boekelheide on the occasion of his 65th birthday (27.XII.84) ~The radical anions of [2.2]paracyclophane-1,9-diene (2) and its 1,10,12,13,15,16-hexadeuterio derivative 2-D6, as well as those of 4,5,7,8-tetramethyl[2.2]paracyclophane-l,9-diene (3) and its 12,13,15,16-tetradeuterio derivative 3-D4, have been studied by ESR spectroscopy. The coupling constants for 2: at 178 K are 0.422 mT for four equivalent olefinic protons and 0.046 and 0.020 mT, each for a set of four equivalent aromatic protons. This hyperfine pattern is consistent with either benzene ring bearing two pairs of equivalent protons and it points to a lowering of the anticipated D,, symmetry. The ESR spectra of 2: are strongly temperature dependent, due to modulation of the two coupling constants of 0.046 and 0.020 mT; these have opposite signs and average to 0.013 mT at 273 K. The experimental findings are interpreted in terms of a transition state of D2h symmetry, 33 kJ/mol above two interconverting equivalent conformations of lower symmetry. Several pieces of evidence suggest that this symmetry is D,, i.e., the benzene rings in 2: are twisted in opposite directions about the vertical axis. Temperature dependence of the ESR spectra, resulting from modulation of the hyperfine interactions with the aromatic protons, is also observed for 2-D6; and 37. In the case of 3', the olefinic protons are, as expected, only equivalent in pairs, the pertinent coupling constants being 0.560 and 0.325 mT. Upon standing at low temperatures, 2; and 3: gradually convert into the radical anions of [2.2]paracyclophane (1) and its 4,5,7,8-tetramethyl derivative, respectively. At higher temperatures, cleavage of one bridging chain in 2: also occurs, with the formation of the radical anion of (E)-4,4'-dimethylstilbene (7). Both reactions of 27 must involve the transient radical anion of [2.2]paracyclophane-l-ene (4) as proved by the observation of the spectra of 1 : and 7: with 4 as the starting material.Introduction. -Replacement of the single by the double bonds in the two bridging alkyl chains of [2.2]paracyclophane (l), to yield the 1,9-diene 2, has only a small effect on the geometry and electronic structure. As shown by the X-ray analyses of 1 [I] and 2 [2],

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Phosphororganische Verbindungen, XXIV. Olefine aus aromatischen Aldehyden mit Diphenylphosphinoxyd‐natrium

Cited by 11 publications

References 12 publications

Influence of 18-Crown-6 Ether Coordination on the Catalytic Activity of Potassium and Calcium Diarylphosphinites in Hydrophosphorylation Reactions

Influence of 18-Crown-6 Ether Coordination on the Catalytic Activity of Potassium and Calcium Diarylphosphinites in Hydrophosphorylation Reactions

Optically active hydrocarbon polymers with aromatic side chains. III. Circular dichroism between 230 and 185 nm of the aromatic chromophore in high molecular weight hydrocarbons

The Radical Anions of [2.2]Paracyclophane‐1,9‐diene and Some of its Derivatives. An Unexpected Conformational Interconversion

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